Missing cache information on x86-64 under Intel TDX (glibc bug 30643) #3

fweimer-rh · 2023-07-18T08:27:12Z

I'm trying to raise awareness for a TDX issue that appears to impact application compatibility:

This was observed before to cause glibc crashes, but the root cause was not addressed:

glibc 2.34 and newer segfault if CPUID leaf 0x2 reports zero

I believe the TDX reference implementation for qemu-kvm is impacted as well because people reported problems when they used it for validating TDX kernel support.

I would like to invite you to join the discussion on libc-alpha. Thanks!

Victor Nogueira says: ==================== net: sched: Fixes for classifiers Four different classifiers (bpf, u32, matchall, and flower) are calling tcf_bind_filter in their callbacks, but arent't undoing it by calling tcf_unbind_filter if their was an error after binding. This patch set fixes all this by calling tcf_unbind_filter in such cases. This set also undoes a refcount decrement in cls_u32 when an update fails under specific conditions which are described in patch #3. v1 -> v2: * Remove blank line after fixes tag * Fix reverse xmas tree issues pointed out by Simon v2 -> v3: * Inline functions cls_bpf_set_parms and fl_set_parms to avoid adding yet another parameter (and a return value at it) to them. * Remove similar fixes for u32 and matchall, which will be sent soon, once we find a way to do the fixes without adding a return parameter to their set_parms functions. v3 -> v4: * Inline mall_set_parms to avoid adding yet another parameter. * Remove set_flags parameter from u32_set_parms and create a separate function for calling tcf_bind_filter and tcf_unbind_filter in case of failure. * Change cover letter title to also encompass refcnt fix for u32 v4 -> v5: * Change back tag to net ==================== Signed-off-by: David S. Miller <[email protected]>

The cited commit holds encap tbl lock unconditionally when setting up dests. But it may cause the following deadlock: PID: 1063722 TASK: ffffa062ca5d0000 CPU: 13 COMMAND: "handler8" #0 [ffffb14de05b7368] __schedule at ffffffffa1d5aa91 #1 [ffffb14de05b7410] schedule at ffffffffa1d5afdb #2 [ffffb14de05b7430] schedule_preempt_disabled at ffffffffa1d5b528 #3 [ffffb14de05b7440] __mutex_lock at ffffffffa1d5d6cb #4 [ffffb14de05b74e8] mutex_lock_nested at ffffffffa1d5ddeb #5 [ffffb14de05b74f8] mlx5e_tc_tun_encap_dests_set at ffffffffc12f2096 [mlx5_core] #6 [ffffb14de05b7568] post_process_attr at ffffffffc12d9fc5 [mlx5_core] #7 [ffffb14de05b75a0] mlx5e_tc_add_fdb_flow at ffffffffc12de877 [mlx5_core] #8 [ffffb14de05b75f0] __mlx5e_add_fdb_flow at ffffffffc12e0eef [mlx5_core] #9 [ffffb14de05b7660] mlx5e_tc_add_flow at ffffffffc12e12f7 [mlx5_core] #10 [ffffb14de05b76b8] mlx5e_configure_flower at ffffffffc12e1686 [mlx5_core] #11 [ffffb14de05b7720] mlx5e_rep_indr_offload at ffffffffc12e3817 [mlx5_core] #12 [ffffb14de05b7730] mlx5e_rep_indr_setup_tc_cb at ffffffffc12e388a [mlx5_core] #13 [ffffb14de05b7740] tc_setup_cb_add at ffffffffa1ab2ba8 #14 [ffffb14de05b77a0] fl_hw_replace_filter at ffffffffc0bdec2f [cls_flower] #15 [ffffb14de05b7868] fl_change at ffffffffc0be6caa [cls_flower] #16 [ffffb14de05b7908] tc_new_tfilter at ffffffffa1ab71f0 [1031218.028143] wait_for_completion+0x24/0x30 [1031218.028589] mlx5e_update_route_decap_flows+0x9a/0x1e0 [mlx5_core] [1031218.029256] mlx5e_tc_fib_event_work+0x1ad/0x300 [mlx5_core] [1031218.029885] process_one_work+0x24e/0x510 Actually no need to hold encap tbl lock if there is no encap action. Fix it by checking if encap action exists or not before holding encap tbl lock. Fixes: 37c3b9f ("net/mlx5e: Prevent encap offload when neigh update is running") Signed-off-by: Chris Mi <[email protected]> Reviewed-by: Vlad Buslov <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]>

syzkaller found zero division error [0] in div_s64_rem() called from get_cycle_time_elapsed(), where sched->cycle_time is the divisor. We have tests in parse_taprio_schedule() so that cycle_time will never be 0, and actually cycle_time is not 0 in get_cycle_time_elapsed(). The problem is that the types of divisor are different; cycle_time is s64, but the argument of div_s64_rem() is s32. syzkaller fed this input and 0x100000000 is cast to s32 to be 0. @TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME={0xc, 0x8, 0x100000000} We use s64 for cycle_time to cast it to ktime_t, so let's keep it and set max for cycle_time. While at it, we prevent overflow in setup_txtime() and add another test in parse_taprio_schedule() to check if cycle_time overflows. Also, we add a new tdc test case for this issue. [0]: divide error: 0000 [#1] PREEMPT SMP KASAN NOPTI CPU: 1 PID: 103 Comm: kworker/1:3 Not tainted 6.5.0-rc1-00330-g60cc1f7d0605 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:div_s64_rem include/linux/math64.h:42 [inline] RIP: 0010:get_cycle_time_elapsed net/sched/sch_taprio.c:223 [inline] RIP: 0010:find_entry_to_transmit+0x252/0x7e0 net/sched/sch_taprio.c:344 Code: 3c 02 00 0f 85 5e 05 00 00 48 8b 4c 24 08 4d 8b bd 40 01 00 00 48 8b 7c 24 48 48 89 c8 4c 29 f8 48 63 f7 48 99 48 89 74 24 70 <48> f7 fe 48 29 d1 48 8d 04 0f 49 89 cc 48 89 44 24 20 49 8d 85 10 RSP: 0018:ffffc90000acf260 EFLAGS: 00010206 RAX: 177450e0347560cf RBX: 0000000000000000 RCX: 177450e0347560cf RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000100000000 RBP: 0000000000000056 R08: 0000000000000000 R09: ffffed10020a0934 R10: ffff8880105049a7 R11: ffff88806cf3a520 R12: ffff888010504800 R13: ffff88800c00d800 R14: ffff8880105049a0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0edf84f0e8 CR3: 000000000d73c002 CR4: 0000000000770ee0 PKRU: 55555554 Call Trace: <TASK> get_packet_txtime net/sched/sch_taprio.c:508 [inline] taprio_enqueue_one+0x900/0xff0 net/sched/sch_taprio.c:577 taprio_enqueue+0x378/0xae0 net/sched/sch_taprio.c:658 dev_qdisc_enqueue+0x46/0x170 net/core/dev.c:3732 __dev_xmit_skb net/core/dev.c:3821 [inline] __dev_queue_xmit+0x1b2f/0x3000 net/core/dev.c:4169 dev_queue_xmit include/linux/netdevice.h:3088 [inline] neigh_resolve_output net/core/neighbour.c:1552 [inline] neigh_resolve_output+0x4a7/0x780 net/core/neighbour.c:1532 neigh_output include/net/neighbour.h:544 [inline] ip6_finish_output2+0x924/0x17d0 net/ipv6/ip6_output.c:135 __ip6_finish_output+0x620/0xaa0 net/ipv6/ip6_output.c:196 ip6_finish_output net/ipv6/ip6_output.c:207 [inline] NF_HOOK_COND include/linux/netfilter.h:292 [inline] ip6_output+0x206/0x410 net/ipv6/ip6_output.c:228 dst_output include/net/dst.h:458 [inline] NF_HOOK.constprop.0+0xea/0x260 include/linux/netfilter.h:303 ndisc_send_skb+0x872/0xe80 net/ipv6/ndisc.c:508 ndisc_send_ns+0xb5/0x130 net/ipv6/ndisc.c:666 addrconf_dad_work+0xc14/0x13f0 net/ipv6/addrconf.c:4175 process_one_work+0x92c/0x13a0 kernel/workqueue.c:2597 worker_thread+0x60f/0x1240 kernel/workqueue.c:2748 kthread+0x2fe/0x3f0 kernel/kthread.c:389 ret_from_fork+0x2c/0x50 arch/x86/entry/entry_64.S:308 </TASK> Modules linked in: Fixes: 4cfd577 ("taprio: Add support for txtime-assist mode") Reported-by: syzkaller <[email protected]> Signed-off-by: Kuniyuki Iwashima <[email protected]> Co-developed-by: Eric Dumazet <[email protected]> Co-developed-by: Pedro Tammela <[email protected]> Acked-by: Vinicius Costa Gomes <[email protected]> Signed-off-by: David S. Miller <[email protected]>

Ido Schimmel says: ==================== nexthop: Nexthop dump fixes Patches #1 and #3 fix two problems related to nexthops and nexthop buckets dump, respectively. Patch #2 is a preparation for the third patch. The pattern described in these patches of splitting the NLMSG_DONE to a separate response is prevalent in other rtnetlink dump callbacks. I don't know if it's because I'm missing something or if this was done intentionally to ensure the message is delivered to user space. After commit 0642840 ("af_netlink: ensure that NLMSG_DONE never fails in dumps") this is no longer necessary and I can improve these dump callbacks assuming this analysis is correct. No regressions in existing tests: # ./fib_nexthops.sh [...] Tests passed: 230 Tests failed: 0 ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

fweimer-rh · 2023-08-22T06:03:57Z

The reference in commit 6e8778f is spurious, it just happens to contain the pair of letters #3.

qxl_mode_dumb_create() dereferences the qobj returned by qxl_gem_object_create_with_handle(), but the handle is the only one holding a reference to it. A potential attacker could guess the returned handle value and closes it between the return of qxl_gem_object_create_with_handle() and the qobj usage, triggering a use-after-free scenario. Reproducer: int dri_fd =-1; struct drm_mode_create_dumb arg = {0}; void gem_close(int handle); void* trigger(void* ptr) { int ret; arg.width = arg.height = 0x20; arg.bpp = 32; ret = ioctl(dri_fd, DRM_IOCTL_MODE_CREATE_DUMB, &arg); if(ret) { perror("[*] DRM_IOCTL_MODE_CREATE_DUMB Failed"); exit(-1); } gem_close(arg.handle); while(1) { struct drm_mode_create_dumb args = {0}; args.width = args.height = 0x20; args.bpp = 32; ret = ioctl(dri_fd, DRM_IOCTL_MODE_CREATE_DUMB, &args); if (ret) { perror("[*] DRM_IOCTL_MODE_CREATE_DUMB Failed"); exit(-1); } printf("[*] DRM_IOCTL_MODE_CREATE_DUMB created, %d\n", args.handle); gem_close(args.handle); } return NULL; } void gem_close(int handle) { struct drm_gem_close args; args.handle = handle; int ret = ioctl(dri_fd, DRM_IOCTL_GEM_CLOSE, &args); // gem close handle if (!ret) printf("gem close handle %d\n", args.handle); } int main(void) { dri_fd= open("/dev/dri/card0", O_RDWR); printf("fd:%d\n", dri_fd); if(dri_fd == -1) return -1; pthread_t tid1; if(pthread_create(&tid1,NULL,trigger,NULL)){ perror("[*] thread_create tid1\n"); return -1; } while (1) { gem_close(arg.handle); } return 0; } This is a KASAN report: ================================================================== BUG: KASAN: slab-use-after-free in qxl_mode_dumb_create+0x3c2/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:69 Write of size 1 at addr ffff88801136c240 by task poc/515 CPU: 1 PID: 515 Comm: poc Not tainted 6.3.0 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014 Call Trace: <TASK> __dump_stack linux/lib/dump_stack.c:88 dump_stack_lvl+0x48/0x70 linux/lib/dump_stack.c:106 print_address_description linux/mm/kasan/report.c:319 print_report+0xd2/0x660 linux/mm/kasan/report.c:430 kasan_report+0xd2/0x110 linux/mm/kasan/report.c:536 __asan_report_store1_noabort+0x17/0x30 linux/mm/kasan/report_generic.c:383 qxl_mode_dumb_create+0x3c2/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:69 drm_mode_create_dumb linux/drivers/gpu/drm/drm_dumb_buffers.c:96 drm_mode_create_dumb_ioctl+0x1f5/0x2d0 linux/drivers/gpu/drm/drm_dumb_buffers.c:102 drm_ioctl_kernel+0x21d/0x430 linux/drivers/gpu/drm/drm_ioctl.c:788 drm_ioctl+0x56f/0xcc0 linux/drivers/gpu/drm/drm_ioctl.c:891 vfs_ioctl linux/fs/ioctl.c:51 __do_sys_ioctl linux/fs/ioctl.c:870 __se_sys_ioctl linux/fs/ioctl.c:856 __x64_sys_ioctl+0x13d/0x1c0 linux/fs/ioctl.c:856 do_syscall_x64 linux/arch/x86/entry/common.c:50 do_syscall_64+0x5b/0x90 linux/arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc linux/arch/x86/entry/entry_64.S:120 RIP: 0033:0x7ff5004ff5f7 Code: 00 00 00 48 8b 05 99 c8 0d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 69 c8 0d 00 f7 d8 64 89 01 48 RSP: 002b:00007ff500408ea8 EFLAGS: 00000286 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff5004ff5f7 RDX: 00007ff500408ec0 RSI: 00000000c02064b2 RDI: 0000000000000003 RBP: 00007ff500408ef0 R08: 0000000000000000 R09: 000000000000002a R10: 0000000000000000 R11: 0000000000000286 R12: 00007fff1c6cdafe R13: 00007fff1c6cdaff R14: 00007ff500408fc0 R15: 0000000000802000 </TASK> Allocated by task 515: kasan_save_stack+0x38/0x70 linux/mm/kasan/common.c:45 kasan_set_track+0x25/0x40 linux/mm/kasan/common.c:52 kasan_save_alloc_info+0x1e/0x40 linux/mm/kasan/generic.c:510 ____kasan_kmalloc linux/mm/kasan/common.c:374 __kasan_kmalloc+0xc3/0xd0 linux/mm/kasan/common.c:383 kasan_kmalloc linux/./include/linux/kasan.h:196 kmalloc_trace+0x48/0xc0 linux/mm/slab_common.c:1066 kmalloc linux/./include/linux/slab.h:580 kzalloc linux/./include/linux/slab.h:720 qxl_bo_create+0x11a/0x610 linux/drivers/gpu/drm/qxl/qxl_object.c:124 qxl_gem_object_create+0xd9/0x360 linux/drivers/gpu/drm/qxl/qxl_gem.c:58 qxl_gem_object_create_with_handle+0xa1/0x180 linux/drivers/gpu/drm/qxl/qxl_gem.c:89 qxl_mode_dumb_create+0x1cd/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:63 drm_mode_create_dumb linux/drivers/gpu/drm/drm_dumb_buffers.c:96 drm_mode_create_dumb_ioctl+0x1f5/0x2d0 linux/drivers/gpu/drm/drm_dumb_buffers.c:102 drm_ioctl_kernel+0x21d/0x430 linux/drivers/gpu/drm/drm_ioctl.c:788 drm_ioctl+0x56f/0xcc0 linux/drivers/gpu/drm/drm_ioctl.c:891 vfs_ioctl linux/fs/ioctl.c:51 __do_sys_ioctl linux/fs/ioctl.c:870 __se_sys_ioctl linux/fs/ioctl.c:856 __x64_sys_ioctl+0x13d/0x1c0 linux/fs/ioctl.c:856 do_syscall_x64 linux/arch/x86/entry/common.c:50 do_syscall_64+0x5b/0x90 linux/arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc linux/arch/x86/entry/entry_64.S:120 Freed by task 515: kasan_save_stack+0x38/0x70 linux/mm/kasan/common.c:45 kasan_set_track+0x25/0x40 linux/mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x60 linux/mm/kasan/generic.c:521 ____kasan_slab_free linux/mm/kasan/common.c:236 ____kasan_slab_free+0x180/0x1f0 linux/mm/kasan/common.c:200 __kasan_slab_free+0x12/0x30 linux/mm/kasan/common.c:244 kasan_slab_free linux/./include/linux/kasan.h:162 slab_free_hook linux/mm/slub.c:1781 slab_free_freelist_hook+0xd2/0x1a0 linux/mm/slub.c:1807 slab_free linux/mm/slub.c:3787 __kmem_cache_free+0x196/0x2d0 linux/mm/slub.c:3800 kfree+0x78/0x120 linux/mm/slab_common.c:1019 qxl_ttm_bo_destroy+0x140/0x1a0 linux/drivers/gpu/drm/qxl/qxl_object.c:49 ttm_bo_release+0x678/0xa30 linux/drivers/gpu/drm/ttm/ttm_bo.c:381 kref_put linux/./include/linux/kref.h:65 ttm_bo_put+0x50/0x80 linux/drivers/gpu/drm/ttm/ttm_bo.c:393 qxl_gem_object_free+0x3e/0x60 linux/drivers/gpu/drm/qxl/qxl_gem.c:42 drm_gem_object_free+0x5c/0x90 linux/drivers/gpu/drm/drm_gem.c:974 kref_put linux/./include/linux/kref.h:65 __drm_gem_object_put linux/./include/drm/drm_gem.h:431 drm_gem_object_put linux/./include/drm/drm_gem.h:444 qxl_gem_object_create_with_handle+0x151/0x180 linux/drivers/gpu/drm/qxl/qxl_gem.c:100 qxl_mode_dumb_create+0x1cd/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:63 drm_mode_create_dumb linux/drivers/gpu/drm/drm_dumb_buffers.c:96 drm_mode_create_dumb_ioctl+0x1f5/0x2d0 linux/drivers/gpu/drm/drm_dumb_buffers.c:102 drm_ioctl_kernel+0x21d/0x430 linux/drivers/gpu/drm/drm_ioctl.c:788 drm_ioctl+0x56f/0xcc0 linux/drivers/gpu/drm/drm_ioctl.c:891 vfs_ioctl linux/fs/ioctl.c:51 __do_sys_ioctl linux/fs/ioctl.c:870 __se_sys_ioctl linux/fs/ioctl.c:856 __x64_sys_ioctl+0x13d/0x1c0 linux/fs/ioctl.c:856 do_syscall_x64 linux/arch/x86/entry/common.c:50 do_syscall_64+0x5b/0x90 linux/arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc linux/arch/x86/entry/entry_64.S:120 The buggy address belongs to the object at ffff88801136c000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 576 bytes inside of freed 1024-byte region [ffff88801136c000, ffff88801136c400) The buggy address belongs to the physical page: page:0000000089fc329b refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11368 head:0000000089fc329b order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff) raw: 000fffffc0010200 ffff888007841dc0 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88801136c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801136c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801136c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88801136c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801136c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Disabling lock debugging due to kernel taint Instead of returning a weak reference to the qxl_bo object, return the created drm_gem_object and let the caller decrement the reference count when it no longer needs it. As a convenience, if the caller is not interested in the gobj object, it can pass NULL to the parameter and the reference counting is descremented internally. The bug and the reproducer were originally found by the Zero Day Initiative project (ZDI-CAN-20940). Link: https://www.zerodayinitiative.com/ Signed-off-by: Wander Lairson Costa <[email protected]> Cc: [email protected] Reviewed-by: Dave Airlie <[email protected]> Signed-off-by: Dave Airlie <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

… via GUP-fast In contrast to most other GUP code, GUP-fast common page table walking code like gup_pte_range() also handles hugetlb pages. But in contrast to other hugetlb page table walking code, it does not look at the hugetlb PTE abstraction whereby we have only a single logical hugetlb PTE per hugetlb page, even when using multiple cont-PTEs underneath -- which is for example what huge_ptep_get() abstracts. So when we have a hugetlb page that is mapped via cont-PTEs, GUP-fast might stumble over a PTE that does not map the head page of a hugetlb page -- not the first "head" PTE of such a cont mapping. Logically, the whole hugetlb page is mapped (entire_mapcount == 1), but we might end up calling gup_must_unshare() with a tail page of a hugetlb page. We only maintain a single PageAnonExclusive flag per hugetlb page (as hugetlb pages cannot get partially COW-shared), stored for the head page. That flag is clear for all tail pages. So when gup_must_unshare() ends up calling PageAnonExclusive() with a tail page of a hugetlb page: 1) With CONFIG_DEBUG_VM_PGFLAGS Stumbles over the: VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page); For example, when executing the COW selftests with 64k hugetlb pages on arm64: [ 61.082187] page:00000000829819ff refcount:3 mapcount:1 mapping:0000000000000000 index:0x1 pfn:0x11ee11 [ 61.082842] head:0000000080f79bf7 order:4 entire_mapcount:1 nr_pages_mapped:0 pincount:2 [ 61.083384] anon flags: 0x17ffff80003000e(referenced|uptodate|dirty|head|mappedtodisk|node=0|zone=2|lastcpupid=0xfffff) [ 61.084101] page_type: 0xffffffff() [ 61.084332] raw: 017ffff800000000 fffffc00037b8401 0000000000000402 0000000200000000 [ 61.084840] raw: 0000000000000010 0000000000000000 00000000ffffffff 0000000000000000 [ 61.085359] head: 017ffff80003000e ffffd9e95b09b788 ffffd9e95b09b788 ffff0007ff63cf71 [ 61.085885] head: 0000000000000000 0000000000000002 00000003ffffffff 0000000000000000 [ 61.086415] page dumped because: VM_BUG_ON_PAGE(PageHuge(page) && !PageHead(page)) [ 61.086914] ------------[ cut here ]------------ [ 61.087220] kernel BUG at include/linux/page-flags.h:990! [ 61.087591] Internal error: Oops - BUG: 00000000f2000800 [#1] SMP [ 61.087999] Modules linked in: ... [ 61.089404] CPU: 0 PID: 4612 Comm: cow Kdump: loaded Not tainted 6.5.0-rc4+ #3 [ 61.089917] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015 [ 61.090409] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 61.090897] pc : gup_must_unshare.part.0+0x64/0x98 [ 61.091242] lr : gup_must_unshare.part.0+0x64/0x98 [ 61.091592] sp : ffff8000825eb940 [ 61.091826] x29: ffff8000825eb940 x28: 0000000000000000 x27: fffffc00037b8440 [ 61.092329] x26: 0400000000000001 x25: 0000000000080101 x24: 0000000000080000 [ 61.092835] x23: 0000000000080100 x22: ffff0000cffb9588 x21: ffff0000c8ec6b58 [ 61.093341] x20: 0000ffffad6b1000 x19: fffffc00037b8440 x18: ffffffffffffffff [ 61.093850] x17: 2864616548656761 x16: 5021202626202965 x15: 6761702865677548 [ 61.094358] x14: 6567615028454741 x13: 2929656761702864 x12: 6165486567615021 [ 61.094858] x11: 00000000ffff7fff x10: 00000000ffff7fff x9 : ffffd9e958b7a1c0 [ 61.095359] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 : 00000000002bffa8 [ 61.095873] x5 : ffff0008bb19e708 x4 : 0000000000000000 x3 : 0000000000000000 [ 61.096380] x2 : 0000000000000000 x1 : ffff0000cf6636c0 x0 : 0000000000000046 [ 61.096894] Call trace: [ 61.097080] gup_must_unshare.part.0+0x64/0x98 [ 61.097392] gup_pte_range+0x3a8/0x3f0 [ 61.097662] gup_pgd_range+0x1ec/0x280 [ 61.097942] lockless_pages_from_mm+0x64/0x1a0 [ 61.098258] internal_get_user_pages_fast+0xe4/0x1d0 [ 61.098612] pin_user_pages_fast+0x58/0x78 [ 61.098917] pin_longterm_test_start+0xf4/0x2b8 [ 61.099243] gup_test_ioctl+0x170/0x3b0 [ 61.099528] __arm64_sys_ioctl+0xa8/0xf0 [ 61.099822] invoke_syscall.constprop.0+0x7c/0xd0 [ 61.100160] el0_svc_common.constprop.0+0xe8/0x100 [ 61.100500] do_el0_svc+0x38/0xa0 [ 61.100736] el0_svc+0x3c/0x198 [ 61.100971] el0t_64_sync_handler+0x134/0x150 [ 61.101280] el0t_64_sync+0x17c/0x180 [ 61.101543] Code: aa1303e0 f00074c1 912b0021 97fffeb2 (d4210000) 2) Without CONFIG_DEBUG_VM_PGFLAGS Always detects "not exclusive" for passed tail pages and refuses to PIN the tail pages R/O, as gup_must_unshare() == true. GUP-fast will fallback to ordinary GUP. As ordinary GUP properly considers the logical hugetlb PTE abstraction in hugetlb_follow_page_mask(), pinning the page will succeed when looking at the PageAnonExclusive on the head page only. So the only real effect of this is that with cont-PTE hugetlb pages, we'll always fallback from GUP-fast to ordinary GUP when not working on the head page, which ends up checking the head page and do the right thing. Consequently, the cow selftests pass with cont-PTE hugetlb pages as well without CONFIG_DEBUG_VM_PGFLAGS. Note that this only applies to anon hugetlb pages that are mapped using cont-PTEs: for example 64k hugetlb pages on a 4k arm64 kernel. ... and only when R/O-pinning (FOLL_PIN) such pages that are mapped into the page table R/O using GUP-fast. On production kernels (and even most debug kernels, that don't set CONFIG_DEBUG_VM_PGFLAGS) this patch should theoretically not be required to be backported. But of course, it does not hurt. Link: https://lkml.kernel.org/r/[email protected] Fixes: a7f2266 ("mm/gup: trigger FAULT_FLAG_UNSHARE when R/O-pinning a possibly shared anonymous page") Signed-off-by: David Hildenbrand <[email protected]> Reported-by: Ryan Roberts <[email protected]> Reviewed-by: Ryan Roberts <[email protected]> Tested-by: Ryan Roberts <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: John Hubbard <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Peter Xu <[email protected]> Cc: Mike Kravetz <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

Hou Tao says: ==================== Fix the unmatched unit_size of bpf_mem_cache From: Hou Tao <[email protected]> Hi, The patchset aims to fix the reported warning [0] when the unit_size of bpf_mem_cache is mismatched with the object size of underly slab-cache. Patch #1 fixes the warning by adjusting size_index according to the value of KMALLOC_MIN_SIZE, so bpf_mem_cache with unit_size which is smaller than KMALLOC_MIN_SIZE or is not aligned with KMALLOC_MIN_SIZE will be redirected to bpf_mem_cache with bigger unit_size. Patch #2 doesn't do prefill for these redirected bpf_mem_cache to save memory. Patch #3 adds further error check in bpf_mem_alloc_init() to ensure the unit_size and object_size are always matched and to prevent potential issues due to the mismatch. Please see individual patches for more details. And comments are always welcome. [0]: https://lore.kernel.org/bpf/[email protected] ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

macb_set_tx_clk() is called under a spinlock but itself calls clk_set_rate() which can sleep. This results in: | BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580 | pps pps1: new PPS source ptp1 | in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 40, name: kworker/u4:3 | preempt_count: 1, expected: 0 | RCU nest depth: 0, expected: 0 | 4 locks held by kworker/u4:3/40: | #0: ffff000003409148 | macb ff0c0000.ethernet: gem-ptp-timer ptp clock registered. | ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x14c/0x51c | #1: ffff8000833cbdd8 ((work_completion)(&pl->resolve)){+.+.}-{0:0}, at: process_one_work+0x14c/0x51c | #2: ffff000004f01578 (&pl->state_mutex){+.+.}-{4:4}, at: phylink_resolve+0x44/0x4e8 | #3: ffff000004f06f50 (&bp->lock){....}-{3:3}, at: macb_mac_link_up+0x40/0x2ac | irq event stamp: 113998 | hardirqs last enabled at (113997): [<ffff800080e8503c>] _raw_spin_unlock_irq+0x30/0x64 | hardirqs last disabled at (113998): [<ffff800080e84478>] _raw_spin_lock_irqsave+0xac/0xc8 | softirqs last enabled at (113608): [<ffff800080010630>] __do_softirq+0x430/0x4e4 | softirqs last disabled at (113597): [<ffff80008001614c>] ____do_softirq+0x10/0x1c | CPU: 0 PID: 40 Comm: kworker/u4:3 Not tainted 6.5.0-11717-g9355ce8b2f50-dirty #368 | Hardware name: ... ZynqMP ... (DT) | Workqueue: events_power_efficient phylink_resolve | Call trace: | dump_backtrace+0x98/0xf0 | show_stack+0x18/0x24 | dump_stack_lvl+0x60/0xac | dump_stack+0x18/0x24 | __might_resched+0x144/0x24c | __might_sleep+0x48/0x98 | __mutex_lock+0x58/0x7b0 | mutex_lock_nested+0x24/0x30 | clk_prepare_lock+0x4c/0xa8 | clk_set_rate+0x24/0x8c | macb_mac_link_up+0x25c/0x2ac | phylink_resolve+0x178/0x4e8 | process_one_work+0x1ec/0x51c | worker_thread+0x1ec/0x3e4 | kthread+0x120/0x124 | ret_from_fork+0x10/0x20 The obvious fix is to move the call to macb_set_tx_clk() out of the protected area. This seems safe as rx and tx are both disabled anyway at this point. It is however not entirely clear what the spinlock shall protect. It could be the read-modify-write access to the NCFGR register, but this is accessed in macb_set_rx_mode() and macb_set_rxcsum_feature() as well without holding the spinlock. It could also be the register accesses done in mog_init_rings() or macb_init_buffers(), but again these functions are called without holding the spinlock in macb_hresp_error_task(). The locking seems fishy in this driver and it might deserve another look before this patch is applied. Fixes: 633e98a ("net: macb: use resolved link config in mac_link_up()") Signed-off-by: Sascha Hauer <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Paolo Abeni <[email protected]>

Syzkaller reported a sleep in atomic context bug relating to the HASHCHK handler logic: BUG: sleeping function called from invalid context at arch/powerpc/kernel/traps.c:1518 in_atomic(): 0, irqs_disabled(): 1, non_block: 0, pid: 25040, name: syz-executor preempt_count: 0, expected: 0 RCU nest depth: 0, expected: 0 no locks held by syz-executor/25040. irq event stamp: 34 hardirqs last enabled at (33): [<c000000000048b38>] prep_irq_for_enabled_exit arch/powerpc/kernel/interrupt.c:56 [inline] hardirqs last enabled at (33): [<c000000000048b38>] interrupt_exit_user_prepare_main+0x148/0x600 arch/powerpc/kernel/interrupt.c:230 hardirqs last disabled at (34): [<c00000000003e6a4>] interrupt_enter_prepare+0x144/0x4f0 arch/powerpc/include/asm/interrupt.h:176 softirqs last enabled at (0): [<c000000000281954>] copy_process+0x16e4/0x4750 kernel/fork.c:2436 softirqs last disabled at (0): [<0000000000000000>] 0x0 CPU: 15 PID: 25040 Comm: syz-executor Not tainted 6.5.0-rc5-00001-g3ccdff6bb06d #3 Hardware name: IBM,9105-22A POWER10 (raw) 0x800200 0xf000006 of:IBM,FW1040.00 (NL1040_021) hv:phyp pSeries Call Trace: [c0000000a8247ce0] [c00000000032b0e4] __might_resched+0x3b4/0x400 kernel/sched/core.c:10189 [c0000000a8247d80] [c0000000008c7dc8] __might_fault+0xa8/0x170 mm/memory.c:5853 [c0000000a8247dc0] [c00000000004160c] do_program_check+0x32c/0xb20 arch/powerpc/kernel/traps.c:1518 [c0000000a8247e50] [c000000000009b2c] program_check_common_virt+0x3bc/0x3c0 To determine if a trap was caused by a HASHCHK instruction, we inspect the user instruction that triggered the trap. However this may sleep if the page needs to be faulted in (get_user_instr() reaches __get_user(), which calls might_fault() and triggers the bug message). Move the HASHCHK handler logic to after we allow IRQs, which is fine because we are only interested in HASHCHK if it's a user space trap. Fixes: 5bcba4e ("powerpc/dexcr: Handle hashchk exception") Signed-off-by: Benjamin Gray <[email protected]> Signed-off-by: Michael Ellerman <[email protected]> Link: https://msgid.link/[email protected]

Sebastian Andrzej Siewior says: ==================== net: hsr: Properly parse HSRv1 supervisor frames. this is a follow-up to https://lore.kernel.org/all/[email protected]/ replacing https://lore.kernel.org/all/[email protected]/ by grabing/ adding tags and reposting with a commit message plus a missing __packed to a struct (#2) plus extending the testsuite to sover HSRv1 which is what broke here (#3-#5). HSRv0 is (was) not affected. ==================== Signed-off-by: David S. Miller <[email protected]>

Fix an error detected by memory sanitizer: ``` ==4033==WARNING: MemorySanitizer: use-of-uninitialized-value #0 0x55fb0fbedfc7 in read_alias_info tools/perf/util/pmu.c:457:6 #1 0x55fb0fbea339 in check_info_data tools/perf/util/pmu.c:1434:2 #2 0x55fb0fbea339 in perf_pmu__check_alias tools/perf/util/pmu.c:1504:9 #3 0x55fb0fbdca85 in parse_events_add_pmu tools/perf/util/parse-events.c:1429:32 #4 0x55fb0f965230 in parse_events_parse tools/perf/util/parse-events.y:299:6 #5 0x55fb0fbdf6b2 in parse_events__scanner tools/perf/util/parse-events.c:1822:8 #6 0x55fb0fbdf8c1 in __parse_events tools/perf/util/parse-events.c:2094:8 #7 0x55fb0fa8ffa9 in parse_events tools/perf/util/parse-events.h:41:9 #8 0x55fb0fa8ffa9 in test_event tools/perf/tests/parse-events.c:2393:8 #9 0x55fb0fa8f458 in test__pmu_events tools/perf/tests/parse-events.c:2551:15 #10 0x55fb0fa6d93f in run_test tools/perf/tests/builtin-test.c:242:9 #11 0x55fb0fa6d93f in test_and_print tools/perf/tests/builtin-test.c:271:8 #12 0x55fb0fa6d082 in __cmd_test tools/perf/tests/builtin-test.c:442:5 #13 0x55fb0fa6d082 in cmd_test tools/perf/tests/builtin-test.c:564:9 #14 0x55fb0f942720 in run_builtin tools/perf/perf.c:322:11 #15 0x55fb0f942486 in handle_internal_command tools/perf/perf.c:375:8 #16 0x55fb0f941dab in run_argv tools/perf/perf.c:419:2 #17 0x55fb0f941dab in main tools/perf/perf.c:535:3 ``` Fixes: 7b723db ("perf pmu: Be lazy about loading event info files from sysfs") Signed-off-by: Ian Rogers <[email protected]> Cc: James Clark <[email protected]> Cc: Kan Liang <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Namhyung Kim <[email protected]>

Fix the deadlock by refactoring the MR cache cleanup flow to flush the workqueue without holding the rb_lock. This adds a race between cache cleanup and creation of new entries which we solve by denied creation of new entries after cache cleanup started. Lockdep: WARNING: possible circular locking dependency detected [ 2785.326074 ] 6.2.0-rc6_for_upstream_debug_2023_01_31_14_02 #1 Not tainted [ 2785.339778 ] ------------------------------------------------------ [ 2785.340848 ] devlink/53872 is trying to acquire lock: [ 2785.341701 ] ffff888124f8c0c8 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}, at: __flush_work+0xc8/0x900 [ 2785.343403 ] [ 2785.343403 ] but task is already holding lock: [ 2785.344464 ] ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib] [ 2785.346273 ] [ 2785.346273 ] which lock already depends on the new lock. [ 2785.346273 ] [ 2785.347720 ] [ 2785.347720 ] the existing dependency chain (in reverse order) is: [ 2785.349003 ] [ 2785.349003 ] -> #1 (&dev->cache.rb_lock){+.+.}-{3:3}: [ 2785.350160 ] __mutex_lock+0x14c/0x15c0 [ 2785.350962 ] delayed_cache_work_func+0x2d1/0x610 [mlx5_ib] [ 2785.352044 ] process_one_work+0x7c2/0x1310 [ 2785.352879 ] worker_thread+0x59d/0xec0 [ 2785.353636 ] kthread+0x28f/0x330 [ 2785.354370 ] ret_from_fork+0x1f/0x30 [ 2785.355135 ] [ 2785.355135 ] -> #0 ((work_completion)(&(&ent->dwork)->work)){+.+.}-{0:0}: [ 2785.356515 ] __lock_acquire+0x2d8a/0x5fe0 [ 2785.357349 ] lock_acquire+0x1c1/0x540 [ 2785.358121 ] __flush_work+0xe8/0x900 [ 2785.358852 ] __cancel_work_timer+0x2c7/0x3f0 [ 2785.359711 ] mlx5_mkey_cache_cleanup+0xfb/0x250 [mlx5_ib] [ 2785.360781 ] mlx5_ib_stage_pre_ib_reg_umr_cleanup+0x16/0x30 [mlx5_ib] [ 2785.361969 ] __mlx5_ib_remove+0x68/0x120 [mlx5_ib] [ 2785.362960 ] mlx5r_remove+0x63/0x80 [mlx5_ib] [ 2785.363870 ] auxiliary_bus_remove+0x52/0x70 [ 2785.364715 ] device_release_driver_internal+0x3c1/0x600 [ 2785.365695 ] bus_remove_device+0x2a5/0x560 [ 2785.366525 ] device_del+0x492/0xb80 [ 2785.367276 ] mlx5_detach_device+0x1a9/0x360 [mlx5_core] [ 2785.368615 ] mlx5_unload_one_devl_locked+0x5a/0x110 [mlx5_core] [ 2785.369934 ] mlx5_devlink_reload_down+0x292/0x580 [mlx5_core] [ 2785.371292 ] devlink_reload+0x439/0x590 [ 2785.372075 ] devlink_nl_cmd_reload+0xaef/0xff0 [ 2785.372973 ] genl_family_rcv_msg_doit.isra.0+0x1bd/0x290 [ 2785.374011 ] genl_rcv_msg+0x3ca/0x6c0 [ 2785.374798 ] netlink_rcv_skb+0x12c/0x360 [ 2785.375612 ] genl_rcv+0x24/0x40 [ 2785.376295 ] netlink_unicast+0x438/0x710 [ 2785.377121 ] netlink_sendmsg+0x7a1/0xca0 [ 2785.377926 ] sock_sendmsg+0xc5/0x190 [ 2785.378668 ] __sys_sendto+0x1bc/0x290 [ 2785.379440 ] __x64_sys_sendto+0xdc/0x1b0 [ 2785.380255 ] do_syscall_64+0x3d/0x90 [ 2785.381031 ] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 2785.381967 ] [ 2785.381967 ] other info that might help us debug this: [ 2785.381967 ] [ 2785.383448 ] Possible unsafe locking scenario: [ 2785.383448 ] [ 2785.384544 ] CPU0 CPU1 [ 2785.385383 ] ---- ---- [ 2785.386193 ] lock(&dev->cache.rb_lock); [ 2785.386940 ] lock((work_completion)(&(&ent->dwork)->work)); [ 2785.388327 ] lock(&dev->cache.rb_lock); [ 2785.389425 ] lock((work_completion)(&(&ent->dwork)->work)); [ 2785.390414 ] [ 2785.390414 ] *** DEADLOCK *** [ 2785.390414 ] [ 2785.391579 ] 6 locks held by devlink/53872: [ 2785.392341 ] #0: ffffffff84c17a50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 [ 2785.393630 ] #1: ffff888142280218 (&devlink->lock_key){+.+.}-{3:3}, at: devlink_get_from_attrs_lock+0x12d/0x2d0 [ 2785.395324 ] #2: ffff8881422d3c38 (&dev->lock_key){+.+.}-{3:3}, at: mlx5_unload_one_devl_locked+0x4a/0x110 [mlx5_core] [ 2785.397322 ] #3: ffffffffa0e59068 (mlx5_intf_mutex){+.+.}-{3:3}, at: mlx5_detach_device+0x60/0x360 [mlx5_core] [ 2785.399231 ] #4: ffff88810e3cb0e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x8d/0x600 [ 2785.400864 ] #5: ffff88817e8f1260 (&dev->cache.rb_lock){+.+.}-{3:3}, at: mlx5_mkey_cache_cleanup+0x77/0x250 [mlx5_ib] Fixes: b958451 ("RDMA/mlx5: Change the cache structure to an RB-tree") Signed-off-by: Shay Drory <[email protected]> Signed-off-by: Michael Guralnik <[email protected]> Signed-off-by: Leon Romanovsky <[email protected]>

The following call trace shows a deadlock issue due to recursive locking of mutex "device_mutex". First lock acquire is in target_for_each_device() and second in target_free_device(). PID: 148266 TASK: ffff8be21ffb5d00 CPU: 10 COMMAND: "iscsi_ttx" #0 [ffffa2bfc9ec3b18] __schedule at ffffffffa8060e7f #1 [ffffa2bfc9ec3ba0] schedule at ffffffffa8061224 #2 [ffffa2bfc9ec3bb8] schedule_preempt_disabled at ffffffffa80615ee #3 [ffffa2bfc9ec3bc8] __mutex_lock at ffffffffa8062fd7 #4 [ffffa2bfc9ec3c40] __mutex_lock_slowpath at ffffffffa80631d3 #5 [ffffa2bfc9ec3c50] mutex_lock at ffffffffa806320c #6 [ffffa2bfc9ec3c68] target_free_device at ffffffffc0935998 [target_core_mod] #7 [ffffa2bfc9ec3c90] target_core_dev_release at ffffffffc092f975 [target_core_mod] #8 [ffffa2bfc9ec3ca0] config_item_put at ffffffffa79d250f #9 [ffffa2bfc9ec3cd0] config_item_put at ffffffffa79d2583 #10 [ffffa2bfc9ec3ce0] target_devices_idr_iter at ffffffffc0933f3a [target_core_mod] #11 [ffffa2bfc9ec3d00] idr_for_each at ffffffffa803f6fc #12 [ffffa2bfc9ec3d60] target_for_each_device at ffffffffc0935670 [target_core_mod] #13 [ffffa2bfc9ec3d98] transport_deregister_session at ffffffffc0946408 [target_core_mod] #14 [ffffa2bfc9ec3dc8] iscsit_close_session at ffffffffc09a44a6 [iscsi_target_mod] #15 [ffffa2bfc9ec3df0] iscsit_close_connection at ffffffffc09a4a88 [iscsi_target_mod] #16 [ffffa2bfc9ec3df8] finish_task_switch at ffffffffa76e5d07 #17 [ffffa2bfc9ec3e78] iscsit_take_action_for_connection_exit at ffffffffc0991c23 [iscsi_target_mod] #18 [ffffa2bfc9ec3ea0] iscsi_target_tx_thread at ffffffffc09a403b [iscsi_target_mod] #19 [ffffa2bfc9ec3f08] kthread at ffffffffa76d8080 #20 [ffffa2bfc9ec3f50] ret_from_fork at ffffffffa8200364 Fixes: 36d4cb4 ("scsi: target: Avoid that EXTENDED COPY commands trigger lock inversion") Signed-off-by: Junxiao Bi <[email protected]> Link: https://lore.kernel.org/r/[email protected] Reviewed-by: Mike Christie <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]>

…mory Introduce an ioctl(), KVM_CREATE_GUEST_MEMFD, to allow creating file-based memory that is tied to a specific KVM virtual machine and whose primary purpose is to serve guest memory. A guest-first memory subsystem allows for optimizations and enhancements that are kludgy or outright infeasible to implement/support in a generic memory subsystem. With guest_memfd, guest protections and mapping sizes are fully decoupled from host userspace mappings. E.g. KVM currently doesn't support mapping memory as writable in the guest without it also being writable in host userspace, as KVM's ABI uses VMA protections to define the allow guest protection. Userspace can fudge this by establishing two mappings, a writable mapping for the guest and readable one for itself, but that’s suboptimal on multiple fronts. Similarly, KVM currently requires the guest mapping size to be a strict subset of the host userspace mapping size, e.g. KVM doesn’t support creating a 1GiB guest mapping unless userspace also has a 1GiB guest mapping. Decoupling the mappings sizes would allow userspace to precisely map only what is needed without impacting guest performance, e.g. to harden against unintentional accesses to guest memory. Decoupling guest and userspace mappings may also allow for a cleaner alternative to high-granularity mappings for HugeTLB, which has reached a bit of an impasse and is unlikely to ever be merged. A guest-first memory subsystem also provides clearer line of sight to things like a dedicated memory pool (for slice-of-hardware VMs) and elimination of "struct page" (for offload setups where userspace _never_ needs to mmap() guest memory). More immediately, being able to map memory into KVM guests without mapping said memory into the host is critical for Confidential VMs (CoCo VMs), the initial use case for guest_memfd. While AMD's SEV and Intel's TDX prevent untrusted software from reading guest private data by encrypting guest memory with a key that isn't usable by the untrusted host, projects such as Protected KVM (pKVM) provide confidentiality and integrity *without* relying on memory encryption. And with SEV-SNP and TDX, accessing guest private memory can be fatal to the host, i.e. KVM must be prevent host userspace from accessing guest memory irrespective of hardware behavior. Attempt #1 to support CoCo VMs was to add a VMA flag to mark memory as being mappable only by KVM (or a similarly enlightened kernel subsystem). That approach was abandoned largely due to it needing to play games with PROT_NONE to prevent userspace from accessing guest memory. Attempt #2 to was to usurp PG_hwpoison to prevent the host from mapping guest private memory into userspace, but that approach failed to meet several requirements for software-based CoCo VMs, e.g. pKVM, as the kernel wouldn't easily be able to enforce a 1:1 page:guest association, let alone a 1:1 pfn:gfn mapping. And using PG_hwpoison does not work for memory that isn't backed by 'struct page', e.g. if devices gain support for exposing encrypted memory regions to guests. Attempt #3 was to extend the memfd() syscall and wrap shmem to provide dedicated file-based guest memory. That approach made it as far as v10 before feedback from Hugh Dickins and Christian Brauner (and others) led to it demise. Hugh's objection was that piggybacking shmem made no sense for KVM's use case as KVM didn't actually *want* the features provided by shmem. I.e. KVM was using memfd() and shmem to avoid having to manage memory directly, not because memfd() and shmem were the optimal solution, e.g. things like read/write/mmap in shmem were dead weight. Christian pointed out flaws with implementing a partial overlay (wrapping only _some_ of shmem), e.g. poking at inode_operations or super_operations would show shmem stuff, but address_space_operations and file_operations would show KVM's overlay. Paraphrashing heavily, Christian suggested KVM stop being lazy and create a proper API. Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/20230418-anfallen-irdisch-6993a61be10b@brauner Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/linux-mm/20230306191944.GA15773@monkey Link: https://lore.kernel.org/linux-mm/[email protected] Cc: Fuad Tabba <[email protected]> Cc: Vishal Annapurve <[email protected]> Cc: Ackerley Tng <[email protected]> Cc: Jarkko Sakkinen <[email protected]> Cc: Maciej Szmigiero <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Quentin Perret <[email protected]> Cc: Michael Roth <[email protected]> Cc: Wang <[email protected]> Cc: Liam Merwick <[email protected]> Cc: Isaku Yamahata <[email protected]> Co-developed-by: Kirill A. Shutemov <[email protected]> Signed-off-by: Kirill A. Shutemov <[email protected]> Co-developed-by: Yu Zhang <[email protected]> Signed-off-by: Yu Zhang <[email protected]> Co-developed-by: Chao Peng <[email protected]> Signed-off-by: Chao Peng <[email protected]> Co-developed-by: Ackerley Tng <[email protected]> Signed-off-by: Ackerley Tng <[email protected]> Co-developed-by: Isaku Yamahata <[email protected]> Signed-off-by: Isaku Yamahata <[email protected]> Co-developed-by: Paolo Bonzini <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]> Co-developed-by: Michael Roth <[email protected]> Signed-off-by: Michael Roth <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Link: https://lore.kernel.org/r/[email protected]

Chuyi Zhou says: ==================== Relax allowlist for open-coded css_task iter Hi, The patchset aims to relax the allowlist for open-coded css_task iter suggested by Alexei[1]. Please see individual patches for more details. And comments are always welcome. Patch summary: * Patch #1: Relax the allowlist and let css_task iter can be used in bpf iters and any sleepable progs. * Patch #2: Add a test in cgroup_iters.c which demonstrates how css_task iters can be combined with cgroup iter. * Patch #3: Add a test to prove css_task iter can be used in normal * sleepable progs. link[1]:https://lore.kernel.org/lkml/CAADnVQKafk_junRyE=-FVAik4hjTRDtThymYGEL8hGTuYoOGpA@mail.gmail.com/ --- Changes in v2: * Fix the incorrect logic in check_css_task_iter_allowlist. Use expected_attach_type to check whether we are using bpf_iters. * Link to v1:https://lore.kernel.org/bpf/[email protected]/T/#m946f9cde86b44a13265d9a44c5738a711eb578fd Changes in v3: * Add a testcase to prove css_task can be used in fentry.s * Link to v2:https://lore.kernel.org/bpf/[email protected]/T/#m14a97041ff56c2df21bc0149449abd275b73f6a3 Changes in v4: * Add Yonghong's ack for patch #1 and patch #2. * Solve Yonghong's comments for patch #2 * Move prog 'iter_css_task_for_each_sleep' from iters_task_failure.c to iters_css_task.c. Use RUN_TESTS to prove we can load this prog. * Link to v3:https://lore.kernel.org/bpf/[email protected]/T/#m3200d8ad29af4ffab97588e297361d0a45d7585d --- ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

When LAN9303 is MDIO-connected two callchains exist into mdio->bus->write(): 1. switch ports 1&2 ("physical" PHYs): virtual (switch-internal) MDIO bus (lan9303_switch_ops->phy_{read|write})-> lan9303_mdio_phy_{read|write} -> mdiobus_{read|write}_nested 2. LAN9303 virtual PHY: virtual MDIO bus (lan9303_phy_{read|write}) -> lan9303_virt_phy_reg_{read|write} -> regmap -> lan9303_mdio_{read|write} If the latter functions just take mutex_lock(&sw_dev->device->bus->mdio_lock) it triggers a LOCKDEP false-positive splat. It's false-positive because the first mdio_lock in the second callchain above belongs to virtual MDIO bus, the second mdio_lock belongs to physical MDIO bus. Consequent annotation in lan9303_mdio_{read|write} as nested lock (similar to lan9303_mdio_phy_{read|write}, it's the same physical MDIO bus) prevents the following splat: WARNING: possible circular locking dependency detected 5.15.71 #1 Not tainted ------------------------------------------------------ kworker/u4:3/609 is trying to acquire lock: ffff000011531c68 (lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock){+.+.}-{3:3}, at: regmap_lock_mutex but task is already holding lock: ffff0000114c44d8 (&bus->mdio_lock){+.+.}-{3:3}, at: mdiobus_read which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (&bus->mdio_lock){+.+.}-{3:3}: lock_acquire __mutex_lock mutex_lock_nested lan9303_mdio_read _regmap_read regmap_read lan9303_probe lan9303_mdio_probe mdio_probe really_probe __driver_probe_device driver_probe_device __device_attach_driver bus_for_each_drv __device_attach device_initial_probe bus_probe_device deferred_probe_work_func process_one_work worker_thread kthread ret_from_fork -> #0 (lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock){+.+.}-{3:3}: __lock_acquire lock_acquire.part.0 lock_acquire __mutex_lock mutex_lock_nested regmap_lock_mutex regmap_read lan9303_phy_read dsa_slave_phy_read __mdiobus_read mdiobus_read get_phy_device mdiobus_scan __mdiobus_register dsa_register_switch lan9303_probe lan9303_mdio_probe mdio_probe really_probe __driver_probe_device driver_probe_device __device_attach_driver bus_for_each_drv __device_attach device_initial_probe bus_probe_device deferred_probe_work_func process_one_work worker_thread kthread ret_from_fork other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&bus->mdio_lock); lock(lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock); lock(&bus->mdio_lock); lock(lan9303_mdio:131:(&lan9303_mdio_regmap_config)->lock); *** DEADLOCK *** 5 locks held by kworker/u4:3/609: #0: ffff000002842938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work #1: ffff80000bacbd60 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work #2: ffff000007645178 (&dev->mutex){....}-{3:3}, at: __device_attach #3: ffff8000096e6e78 (dsa2_mutex){+.+.}-{3:3}, at: dsa_register_switch #4: ffff0000114c44d8 (&bus->mdio_lock){+.+.}-{3:3}, at: mdiobus_read stack backtrace: CPU: 1 PID: 609 Comm: kworker/u4:3 Not tainted 5.15.71 #1 Workqueue: events_unbound deferred_probe_work_func Call trace: dump_backtrace show_stack dump_stack_lvl dump_stack print_circular_bug check_noncircular __lock_acquire lock_acquire.part.0 lock_acquire __mutex_lock mutex_lock_nested regmap_lock_mutex regmap_read lan9303_phy_read dsa_slave_phy_read __mdiobus_read mdiobus_read get_phy_device mdiobus_scan __mdiobus_register dsa_register_switch lan9303_probe lan9303_mdio_probe ... Cc: [email protected] Fixes: dc70058 ("net: dsa: LAN9303: add MDIO managed mode support") Signed-off-by: Alexander Sverdlin <[email protected]> Reviewed-by: Andrew Lunn <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Paolo Abeni <[email protected]>

KMSAN reported the following uninit-value access issue: ===================================================== BUG: KMSAN: uninit-value in virtio_transport_recv_pkt+0x1dfb/0x26a0 net/vmw_vsock/virtio_transport_common.c:1421 virtio_transport_recv_pkt+0x1dfb/0x26a0 net/vmw_vsock/virtio_transport_common.c:1421 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Uninit was stored to memory at: virtio_transport_space_update net/vmw_vsock/virtio_transport_common.c:1274 [inline] virtio_transport_recv_pkt+0x1ee8/0x26a0 net/vmw_vsock/virtio_transport_common.c:1415 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 Uninit was created at: slab_post_alloc_hook+0x105/0xad0 mm/slab.h:767 slab_alloc_node mm/slub.c:3478 [inline] kmem_cache_alloc_node+0x5a2/0xaf0 mm/slub.c:3523 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:559 __alloc_skb+0x2fd/0x770 net/core/skbuff.c:650 alloc_skb include/linux/skbuff.h:1286 [inline] virtio_vsock_alloc_skb include/linux/virtio_vsock.h:66 [inline] virtio_transport_alloc_skb+0x90/0x11e0 net/vmw_vsock/virtio_transport_common.c:58 virtio_transport_reset_no_sock net/vmw_vsock/virtio_transport_common.c:957 [inline] virtio_transport_recv_pkt+0x1279/0x26a0 net/vmw_vsock/virtio_transport_common.c:1387 vsock_loopback_work+0x3bb/0x5a0 net/vmw_vsock/vsock_loopback.c:120 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0xff6/0x1e60 kernel/workqueue.c:2703 worker_thread+0xeca/0x14d0 kernel/workqueue.c:2784 kthread+0x3cc/0x520 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 CPU: 1 PID: 10664 Comm: kworker/1:5 Not tainted 6.6.0-rc3-00146-g9f3ebbef746f #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2-1.fc38 04/01/2014 Workqueue: vsock-loopback vsock_loopback_work ===================================================== The following simple reproducer can cause the issue described above: int main(void) { int sock; struct sockaddr_vm addr = { .svm_family = AF_VSOCK, .svm_cid = VMADDR_CID_ANY, .svm_port = 1234, }; sock = socket(AF_VSOCK, SOCK_STREAM, 0); connect(sock, (struct sockaddr *)&addr, sizeof(addr)); return 0; } This issue occurs because the `buf_alloc` and `fwd_cnt` fields of the `struct virtio_vsock_hdr` are not initialized when a new skb is allocated in `virtio_transport_init_hdr()`. This patch resolves the issue by initializing these fields during allocation. Fixes: 71dc9ec ("virtio/vsock: replace virtio_vsock_pkt with sk_buff") Reported-and-tested-by: [email protected] Closes: https://syzkaller.appspot.com/bug?extid=0c8ce1da0ac31abbadcd Signed-off-by: Shigeru Yoshida <[email protected]> Reviewed-by: Stefano Garzarella <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

…mory Introduce an ioctl(), KVM_CREATE_GUEST_MEMFD, to allow creating file-based memory that is tied to a specific KVM virtual machine and whose primary purpose is to serve guest memory. A guest-first memory subsystem allows for optimizations and enhancements that are kludgy or outright infeasible to implement/support in a generic memory subsystem. With guest_memfd, guest protections and mapping sizes are fully decoupled from host userspace mappings. E.g. KVM currently doesn't support mapping memory as writable in the guest without it also being writable in host userspace, as KVM's ABI uses VMA protections to define the allow guest protection. Userspace can fudge this by establishing two mappings, a writable mapping for the guest and readable one for itself, but that’s suboptimal on multiple fronts. Similarly, KVM currently requires the guest mapping size to be a strict subset of the host userspace mapping size, e.g. KVM doesn’t support creating a 1GiB guest mapping unless userspace also has a 1GiB guest mapping. Decoupling the mappings sizes would allow userspace to precisely map only what is needed without impacting guest performance, e.g. to harden against unintentional accesses to guest memory. Decoupling guest and userspace mappings may also allow for a cleaner alternative to high-granularity mappings for HugeTLB, which has reached a bit of an impasse and is unlikely to ever be merged. A guest-first memory subsystem also provides clearer line of sight to things like a dedicated memory pool (for slice-of-hardware VMs) and elimination of "struct page" (for offload setups where userspace _never_ needs to mmap() guest memory). More immediately, being able to map memory into KVM guests without mapping said memory into the host is critical for Confidential VMs (CoCo VMs), the initial use case for guest_memfd. While AMD's SEV and Intel's TDX prevent untrusted software from reading guest private data by encrypting guest memory with a key that isn't usable by the untrusted host, projects such as Protected KVM (pKVM) provide confidentiality and integrity *without* relying on memory encryption. And with SEV-SNP and TDX, accessing guest private memory can be fatal to the host, i.e. KVM must be prevent host userspace from accessing guest memory irrespective of hardware behavior. Attempt #1 to support CoCo VMs was to add a VMA flag to mark memory as being mappable only by KVM (or a similarly enlightened kernel subsystem). That approach was abandoned largely due to it needing to play games with PROT_NONE to prevent userspace from accessing guest memory. Attempt #2 to was to usurp PG_hwpoison to prevent the host from mapping guest private memory into userspace, but that approach failed to meet several requirements for software-based CoCo VMs, e.g. pKVM, as the kernel wouldn't easily be able to enforce a 1:1 page:guest association, let alone a 1:1 pfn:gfn mapping. And using PG_hwpoison does not work for memory that isn't backed by 'struct page', e.g. if devices gain support for exposing encrypted memory regions to guests. Attempt #3 was to extend the memfd() syscall and wrap shmem to provide dedicated file-based guest memory. That approach made it as far as v10 before feedback from Hugh Dickins and Christian Brauner (and others) led to it demise. Hugh's objection was that piggybacking shmem made no sense for KVM's use case as KVM didn't actually *want* the features provided by shmem. I.e. KVM was using memfd() and shmem to avoid having to manage memory directly, not because memfd() and shmem were the optimal solution, e.g. things like read/write/mmap in shmem were dead weight. Christian pointed out flaws with implementing a partial overlay (wrapping only _some_ of shmem), e.g. poking at inode_operations or super_operations would show shmem stuff, but address_space_operations and file_operations would show KVM's overlay. Paraphrashing heavily, Christian suggested KVM stop being lazy and create a proper API. Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/all/20230418-anfallen-irdisch-6993a61be10b@brauner Link: https://lore.kernel.org/all/[email protected] Link: https://lore.kernel.org/linux-mm/20230306191944.GA15773@monkey Link: https://lore.kernel.org/linux-mm/[email protected] Cc: Fuad Tabba <[email protected]> Cc: Vishal Annapurve <[email protected]> Cc: Ackerley Tng <[email protected]> Cc: Jarkko Sakkinen <[email protected]> Cc: Maciej Szmigiero <[email protected]> Cc: Vlastimil Babka <[email protected]> Cc: David Hildenbrand <[email protected]> Cc: Quentin Perret <[email protected]> Cc: Michael Roth <[email protected]> Cc: Wang <[email protected]> Cc: Liam Merwick <[email protected]> Cc: Isaku Yamahata <[email protected]> Co-developed-by: Kirill A. Shutemov <[email protected]> Signed-off-by: Kirill A. Shutemov <[email protected]> Co-developed-by: Yu Zhang <[email protected]> Signed-off-by: Yu Zhang <[email protected]> Co-developed-by: Chao Peng <[email protected]> Signed-off-by: Chao Peng <[email protected]> Co-developed-by: Ackerley Tng <[email protected]> Signed-off-by: Ackerley Tng <[email protected]> Co-developed-by: Isaku Yamahata <[email protected]> Signed-off-by: Isaku Yamahata <[email protected]> Co-developed-by: Paolo Bonzini <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]> Co-developed-by: Michael Roth <[email protected]> Signed-off-by: Michael Roth <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-Id: <[email protected]> Reviewed-by: Fuad Tabba <[email protected]> Tested-by: Fuad Tabba <[email protected]> Reviewed-by: Xiaoyao Li <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>

Andrii Nakryiko says: ==================== BPF control flow graph and precision backtrack fixes A small fix to BPF verifier's CFG logic around handling and reporting ldimm64 instructions. Patch #1 was previously submitted separately ([0]), and so this patch set supersedes that patch. Second patch is fixing obscure corner case in mark_chain_precise() logic. See patch for details. Patch #3 adds a dedicated test, however fragile it might. [0] https://patchwork.kernel.org/project/netdevbpf/patch/[email protected]/ ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

This allows it to break the following circular locking dependency. Aug 10 07:01:29 dg1test kernel: ====================================================== Aug 10 07:01:29 dg1test kernel: WARNING: possible circular locking dependency detected Aug 10 07:01:29 dg1test kernel: 6.4.0-rc7+ #10 Not tainted Aug 10 07:01:29 dg1test kernel: ------------------------------------------------------ Aug 10 07:01:29 dg1test kernel: wireplumber/2236 is trying to acquire lock: Aug 10 07:01:29 dg1test kernel: ffff8fca5320da18 (&fctx->lock){-...}-{2:2}, at: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: but task is already holding lock: Aug 10 07:01:29 dg1test kernel: ffff8fca41208610 (&event->list_lock#2){-...}-{2:2}, at: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: which lock already depends on the new lock. Aug 10 07:01:29 dg1test kernel: the existing dependency chain (in reverse order) is: Aug 10 07:01:29 dg1test kernel: -> #3 (&event->list_lock#2){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: -> #2 (&device->intr.lock){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_inth_allow+0x2c/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_state+0x181/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_allow+0x63/0xd0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_uevent_mthd+0x4d/0x70 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_ioctl+0x10b/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_object_mthd+0xa8/0x1f0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_event_allow+0x2a/0xa0 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_enable_signaling+0x78/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: __dma_fence_enable_signaling+0x5e/0x100 Aug 10 07:01:29 dg1test kernel: dma_fence_add_callback+0x4b/0xd0 Aug 10 07:01:29 dg1test kernel: nouveau_cli_work_queue+0xae/0x110 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_gem_object_close+0x1d1/0x2a0 [nouveau] Aug 10 07:01:29 dg1test kernel: drm_gem_handle_delete+0x70/0xe0 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl_kernel+0xa5/0x150 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl+0x256/0x490 [drm] Aug 10 07:01:29 dg1test kernel: nouveau_drm_ioctl+0x5a/0xb0 [nouveau] Aug 10 07:01:29 dg1test kernel: __x64_sys_ioctl+0x91/0xd0 Aug 10 07:01:29 dg1test kernel: do_syscall_64+0x3c/0x90 Aug 10 07:01:29 dg1test kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Aug 10 07:01:29 dg1test kernel: -> #1 (&event->refs_lock#4){....}-{2:2}: Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_state+0x37/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy_allow+0x63/0xd0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_uevent_mthd+0x4d/0x70 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_ioctl+0x10b/0x250 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_object_mthd+0xa8/0x1f0 [nouveau] Aug 10 07:01:29 dg1test kernel: nvif_event_allow+0x2a/0xa0 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_enable_signaling+0x78/0x80 [nouveau] Aug 10 07:01:29 dg1test kernel: __dma_fence_enable_signaling+0x5e/0x100 Aug 10 07:01:29 dg1test kernel: dma_fence_add_callback+0x4b/0xd0 Aug 10 07:01:29 dg1test kernel: nouveau_cli_work_queue+0xae/0x110 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_gem_object_close+0x1d1/0x2a0 [nouveau] Aug 10 07:01:29 dg1test kernel: drm_gem_handle_delete+0x70/0xe0 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl_kernel+0xa5/0x150 [drm] Aug 10 07:01:29 dg1test kernel: drm_ioctl+0x256/0x490 [drm] Aug 10 07:01:29 dg1test kernel: nouveau_drm_ioctl+0x5a/0xb0 [nouveau] Aug 10 07:01:29 dg1test kernel: __x64_sys_ioctl+0x91/0xd0 Aug 10 07:01:29 dg1test kernel: do_syscall_64+0x3c/0x90 Aug 10 07:01:29 dg1test kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Aug 10 07:01:29 dg1test kernel: -> #0 (&fctx->lock){-...}-{2:2}: Aug 10 07:01:29 dg1test kernel: __lock_acquire+0x14e3/0x2240 Aug 10 07:01:29 dg1test kernel: lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_client_event+0xf/0x20 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x9b/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: other info that might help us debug this: Aug 10 07:01:29 dg1test kernel: Chain exists of: &fctx->lock --> &device->intr.lock --> &event->list_lock#2 Aug 10 07:01:29 dg1test kernel: Possible unsafe locking scenario: Aug 10 07:01:29 dg1test kernel: CPU0 CPU1 Aug 10 07:01:29 dg1test kernel: ---- ---- Aug 10 07:01:29 dg1test kernel: lock(&event->list_lock#2); Aug 10 07:01:29 dg1test kernel: lock(&device->intr.lock); Aug 10 07:01:29 dg1test kernel: lock(&event->list_lock#2); Aug 10 07:01:29 dg1test kernel: lock(&fctx->lock); Aug 10 07:01:29 dg1test kernel: *** DEADLOCK *** Aug 10 07:01:29 dg1test kernel: 2 locks held by wireplumber/2236: Aug 10 07:01:29 dg1test kernel: #0: ffff8fca53177bf8 (&device->intr.lock){-...}-{2:2}, at: nvkm_intr+0x29/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: #1: ffff8fca41208610 (&event->list_lock#2){-...}-{2:2}, at: nvkm_event_ntfy+0x50/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: stack backtrace: Aug 10 07:01:29 dg1test kernel: CPU: 6 PID: 2236 Comm: wireplumber Not tainted 6.4.0-rc7+ #10 Aug 10 07:01:29 dg1test kernel: Hardware name: Gigabyte Technology Co., Ltd. Z390 I AORUS PRO WIFI/Z390 I AORUS PRO WIFI-CF, BIOS F8 11/05/2021 Aug 10 07:01:29 dg1test kernel: Call Trace: Aug 10 07:01:29 dg1test kernel: <TASK> Aug 10 07:01:29 dg1test kernel: dump_stack_lvl+0x5b/0x90 Aug 10 07:01:29 dg1test kernel: check_noncircular+0xe2/0x110 Aug 10 07:01:29 dg1test kernel: __lock_acquire+0x14e3/0x2240 Aug 10 07:01:29 dg1test kernel: lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: ? nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: ? lock_acquire+0xc8/0x2a0 Aug 10 07:01:29 dg1test kernel: _raw_spin_lock_irqsave+0x4b/0x70 Aug 10 07:01:29 dg1test kernel: ? nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nouveau_fence_wait_uevent_handler+0x2b/0x100 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_client_event+0xf/0x20 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_event_ntfy+0x9b/0xf0 [nouveau] Aug 10 07:01:29 dg1test kernel: ga100_fifo_nonstall_intr+0x24/0x30 [nouveau] Aug 10 07:01:29 dg1test kernel: nvkm_intr+0x12c/0x240 [nouveau] Aug 10 07:01:29 dg1test kernel: __handle_irq_event_percpu+0x88/0x240 Aug 10 07:01:29 dg1test kernel: handle_irq_event+0x38/0x80 Aug 10 07:01:29 dg1test kernel: handle_edge_irq+0xa3/0x240 Aug 10 07:01:29 dg1test kernel: __common_interrupt+0x72/0x160 Aug 10 07:01:29 dg1test kernel: common_interrupt+0x60/0xe0 Aug 10 07:01:29 dg1test kernel: asm_common_interrupt+0x26/0x40 Aug 10 07:01:29 dg1test kernel: RIP: 0033:0x7fb66174d700 Aug 10 07:01:29 dg1test kernel: Code: c1 e2 05 29 ca 8d 0c 10 0f be 07 84 c0 75 eb 89 c8 c3 0f 1f 84 00 00 00 00 00 f3 0f 1e fa e9 d7 0f fc ff 0f 1f 80 00 00 00 00 <f3> 0f 1e fa e9 c7 0f fc> Aug 10 07:01:29 dg1test kernel: RSP: 002b:00007ffdd3c48438 EFLAGS: 00000206 Aug 10 07:01:29 dg1test kernel: RAX: 000055bb758763c0 RBX: 000055bb758752c0 RCX: 00000000000028b0 Aug 10 07:01:29 dg1test kernel: RDX: 000055bb758752c0 RSI: 000055bb75887490 RDI: 000055bb75862950 Aug 10 07:01:29 dg1test kernel: RBP: 00007ffdd3c48490 R08: 000055bb75873b10 R09: 0000000000000001 Aug 10 07:01:29 dg1test kernel: R10: 0000000000000004 R11: 000055bb7587f000 R12: 000055bb75887490 Aug 10 07:01:29 dg1test kernel: R13: 000055bb757f6280 R14: 000055bb758875c0 R15: 000055bb757f6280 Aug 10 07:01:29 dg1test kernel: </TASK> Signed-off-by: Dave Airlie <[email protected]> Tested-by: Danilo Krummrich <[email protected]> Reviewed-by: Danilo Krummrich <[email protected]> Signed-off-by: Danilo Krummrich <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

…f-times' Eduard Zingerman says: ==================== verify callbacks as if they are called unknown number of times This series updates verifier logic for callback functions handling. Current master simulates callback body execution exactly once, which leads to verifier not detecting unsafe programs like below: static int unsafe_on_zero_iter_cb(__u32 idx, struct num_context *ctx) { ctx->i = 0; return 0; } SEC("?raw_tp") int unsafe_on_zero_iter(void *unused) { struct num_context loop_ctx = { .i = 32 }; __u8 choice_arr[2] = { 0, 1 }; bpf_loop(100, unsafe_on_zero_iter_cb, &loop_ctx, 0); return choice_arr[loop_ctx.i]; } This was reported previously in [0]. The basic idea of the fix is to schedule callback entry state for verification in env->head until some identical, previously visited state in current DFS state traversal is found. Same logic as with open coded iterators, and builds on top recent fixes [1] for those. The series is structured as follows: - patches #1,2,3 update strobemeta, xdp_synproxy selftests and bpf_loop_bench benchmark to allow convergence of the bpf_loop callback states; - patches #4,5 just shuffle the code a bit; - patch #6 is the main part of the series; - patch #7 adds test cases for #6; - patch #8 extend patch #6 with same speculative scalar widening logic, as used for open coded iterators; - patch #9 adds test cases for #8; - patch #10 extends patch #6 to track maximal number of callback executions specifically for bpf_loop(); - patch #11 adds test cases for #10. Veristat results comparing this series to master+patches #1,2,3 using selftests show the following difference: File Program States (A) States (B) States (DIFF) ------------------------- ------------- ---------- ---------- ------------- bpf_loop_bench.bpf.o benchmark 1 2 +1 (+100.00%) pyperf600_bpf_loop.bpf.o on_event 322 407 +85 (+26.40%) strobemeta_bpf_loop.bpf.o on_event 113 151 +38 (+33.63%) xdp_synproxy_kern.bpf.o syncookie_tc 341 291 -50 (-14.66%) xdp_synproxy_kern.bpf.o syncookie_xdp 344 301 -43 (-12.50%) Veristat results comparing this series to master using Tetragon BPF files [2] also show some differences. States diff varies from +2% to +15% on 23 programs out of 186, no new failures. Changelog: - V3 [5] -> V4, changes suggested by Andrii: - validate mark_chain_precision() result in patch #10; - renaming s/cumulative_callback_depth/callback_unroll_depth/. - V2 [4] -> V3: - fixes in expected log messages for test cases: - callback_result_precise; - parent_callee_saved_reg_precise_with_callback; - parent_stack_slot_precise_with_callback; - renamings (suggested by Alexei): - s/callback_iter_depth/cumulative_callback_depth/ - s/is_callback_iter_next/calls_callback/ - s/mark_callback_iter_next/mark_calls_callback/ - prepare_func_exit() updated to exit with -EFAULT when callee->in_callback_fn is true but calls_callback() is not true for callsite; - test case 'bpf_loop_iter_limit_nested' rewritten to use return value check instead of verifier log message checks (suggested by Alexei). - V1 [3] -> V2, changes suggested by Andrii: - small changes for error handling code in __check_func_call(); - callback body processing log is now matched in relevant verifier_subprog_precision.c tests; - R1 passed to bpf_loop() is now always marked as precise; - log level 2 message for bpf_loop() iteration termination instead of iteration depth messages; - __no_msg macro removed; - bpf_loop_iter_limit_nested updated to avoid using __no_msg; - commit message for patch #3 updated according to Alexei's request. [0] https://lore.kernel.org/bpf/CA+vRuzPChFNXmouzGG+wsy=6eMcfr1mFG0F3g7rbg-sedGKW3w@mail.gmail.com/ [1] https://lore.kernel.org/bpf/[email protected]/ [2] [email protected]:cilium/tetragon.git [3] https://lore.kernel.org/bpf/[email protected]/T/#t [4] https://lore.kernel.org/bpf/[email protected]/T/#t [5] https://lore.kernel.org/bpf/[email protected]/T/#t ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

When scanning namespaces, it is possible to get valid data from the first call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second call in nvme_update_ns_info_block(). In particular, if the NSID becomes inactive between the two commands, a storage device may return a buffer filled with zero as per 4.1.5.1. In this case, we can get a kernel crash due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will be set to zero. PID: 326 TASK: ffff95fec3cd8000 CPU: 29 COMMAND: "kworker/u98:10" #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595 #6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6 #7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926 [exception RIP: blk_stack_limits+434] RIP: ffffffff92191872 RSP: ffffad8f8702fc80 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff95efa0c91800 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: 00000000ffffffff R8: ffff95fec7df35a8 R9: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: ffff95fed33c09a8 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core] #9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core] This happened when the check for valid data was moved out of nvme_identify_ns() into one of the callers. Fix this by checking in both callers. Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186 Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan") Cc: [email protected] Signed-off-by: Ewan D. Milne <[email protected]> Signed-off-by: Keith Busch <[email protected]>

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be dereferenced as wrong struct in irdma_free_pending_cqp_request(). PID: 3669 TASK: ffff88aef892c000 CPU: 28 COMMAND: "kworker/28:0" #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34 #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2 #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f #3 [fffffe0000549eb8] do_nmi at ffffffff81079582 #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4 [exception RIP: native_queued_spin_lock_slowpath+1291] RIP: ffffffff8127e72b RSP: ffff88aa841ef778 RFLAGS: 00000046 RAX: 0000000000000000 RBX: ffff88b01f849700 RCX: ffffffff8127e47e RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff83857ec0 RBP: ffff88afe3e4efc8 R8: ffffed15fc7c9dfa R9: ffffed15fc7c9dfa R10: 0000000000000001 R11: ffffed15fc7c9df9 R12: 0000000000740000 R13: ffff88b01f849708 R14: 0000000000000003 R15: ffffed1603f092e1 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0000 -- <NMI exception stack> -- #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4 #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363 #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma] #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma] #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma] #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma] #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6 #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278 #15 [ffff88aa841efb88] device_del at ffffffff82179d23 #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice] #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice] #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff #20 [ffff88aa841eff10] kthread at ffffffff811d87a0 #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions") Link: https://lore.kernel.org/r/[email protected] Suggested-by: "Ismail, Mustafa" <[email protected]> Signed-off-by: Shifeng Li <[email protected]> Reviewed-by: Shiraz Saleem <[email protected]> Signed-off-by: Jason Gunthorpe <[email protected]>

When working on LED support for r8169 I got the following lockdep warning. Easiest way to prevent this scenario seems to be to take the RTNL lock before the trigger_data lock in set_device_name(). ====================================================== WARNING: possible circular locking dependency detected 6.7.0-rc2-next-20231124+ #2 Not tainted ------------------------------------------------------ bash/383 is trying to acquire lock: ffff888103aa1c68 (&trigger_data->lock){+.+.}-{3:3}, at: netdev_trig_notify+0xec/0x190 [ledtrig_netdev] but task is already holding lock: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (rtnl_mutex){+.+.}-{3:3}: __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 rtnl_lock+0x12/0x20 set_device_name+0xa9/0x120 [ledtrig_netdev] netdev_trig_activate+0x1a1/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 -> #0 (&trigger_data->lock){+.+.}-{3:3}: __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 __mutex_lock+0x9b/0xb50 mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(rtnl_mutex); lock(&trigger_data->lock); lock(rtnl_mutex); lock(&trigger_data->lock); *** DEADLOCK *** 8 locks held by bash/383: #0: ffff888103ff33f0 (sb_writers#3){.+.+}-{0:0}, at: ksys_write+0x6c/0xf0 #1: ffff888103aa1e88 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x114/0x210 #2: ffff8881036f1890 (kn->active#82){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x11d/0x210 #3: ffff888108e2c358 (&led_cdev->led_access){+.+.}-{3:3}, at: led_trigger_write+0x30/0x140 #4: ffffffff8cdd9e10 (triggers_list_lock){++++}-{3:3}, at: led_trigger_write+0x75/0x140 #5: ffff888108e2c270 (&led_cdev->trigger_lock){++++}-{3:3}, at: led_trigger_write+0xe3/0x140 #6: ffffffff8cdde3d0 (pernet_ops_rwsem){++++}-{3:3}, at: register_netdevice_notifier+0x1c/0x120 #7: ffffffff8cddf808 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x12/0x20 stack backtrace: CPU: 0 PID: 383 Comm: bash Not tainted 6.7.0-rc2-next-20231124+ #2 Hardware name: Default string Default string/Default string, BIOS ADLN.M6.SODIMM.ZB.CY.015 08/08/2023 Call Trace: <TASK> dump_stack_lvl+0x5c/0xd0 dump_stack+0x10/0x20 print_circular_bug+0x2dd/0x410 check_noncircular+0x131/0x150 __lock_acquire+0x1459/0x25a0 lock_acquire+0xc8/0x2d0 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] __mutex_lock+0x9b/0xb50 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __this_cpu_preempt_check+0x13/0x20 ? netdev_trig_notify+0xec/0x190 [ledtrig_netdev] ? __cancel_work_timer+0x11c/0x1b0 ? __mutex_lock+0x123/0xb50 mutex_lock_nested+0x16/0x20 ? mutex_lock_nested+0x16/0x20 netdev_trig_notify+0xec/0x190 [ledtrig_netdev] call_netdevice_register_net_notifiers+0x5a/0x100 register_netdevice_notifier+0x85/0x120 netdev_trig_activate+0x1d4/0x230 [ledtrig_netdev] led_trigger_set+0x172/0x2c0 ? preempt_count_add+0x49/0xc0 led_trigger_write+0xf1/0x140 sysfs_kf_bin_write+0x5d/0x80 kernfs_fop_write_iter+0x15d/0x210 vfs_write+0x1f0/0x510 ksys_write+0x6c/0xf0 __x64_sys_write+0x14/0x20 do_syscall_64+0x3f/0xf0 entry_SYSCALL_64_after_hwframe+0x6c/0x74 RIP: 0033:0x7f269055d034 Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d 35 c3 0d 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 48 83 ec 28 48 89 54 24 18 48 RSP: 002b:00007ffddb7ef748 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000007 RCX: 00007f269055d034 RDX: 0000000000000007 RSI: 000055bf5f4af3c0 RDI: 0000000000000001 RBP: 000055bf5f4af3c0 R08: 0000000000000073 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000007 R13: 00007f26906325c0 R14: 00007f269062ff20 R15: 0000000000000000 </TASK> Fixes: d5e0126 ("leds: trigger: netdev: add additional specific link speed mode") Cc: [email protected] Signed-off-by: Heiner Kallweit <[email protected]> Reviewed-by: Andrew Lunn <[email protected]> Acked-by: Lee Jones <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

The cited change refactored mlx5e_tc_del_fdb_peer_flow() to only clear DUP flag when list of peer flows has become empty. However, if any concurrent user holds a reference to a peer flow (for example, the neighbor update workqueue task is updating peer flow's parent encap entry concurrently), then the flow will not be removed from the peer list and, consecutively, DUP flag will remain set. Since mlx5e_tc_del_fdb_peers_flow() calls mlx5e_tc_del_fdb_peer_flow() for every possible peer index the algorithm will try to remove the flow from eswitch instances that it has never peered with causing either NULL pointer dereference when trying to remove the flow peer list head of peer_index that was never initialized or a warning if the list debug config is enabled[0]. Fix the issue by always removing the peer flow from the list even when not releasing the last reference to it. [0]: [ 3102.985806] ------------[ cut here ]------------ [ 3102.986223] list_del corruption, ffff888139110698->next is NULL [ 3102.986757] WARNING: CPU: 2 PID: 22109 at lib/list_debug.c:53 __list_del_entry_valid_or_report+0x4f/0xc0 [ 3102.987561] Modules linked in: act_ct nf_flow_table bonding act_tunnel_key act_mirred act_skbedit vxlan cls_matchall nfnetlink_cttimeout act_gact cls_flower sch_ingress mlx5_vdpa vringh vhost_iotlb vdpa openvswitch nsh xt_MASQUERADE nf_conntrack_netlink nfnetlink iptable_nat xt_addrtype xt_conntrack nf_nat br_netfilter rpcsec_gss_krb5 auth_rpcg ss oid_registry overlay rpcrdma rdma_ucm ib_iser libiscsi scsi_transport_iscsi ib_umad rdma_cm ib_ipoib iw_cm ib_cm mlx5_ib ib_uverbs ib_core mlx5_core [last unloaded: bonding] [ 3102.991113] CPU: 2 PID: 22109 Comm: revalidator28 Not tainted 6.6.0-rc6+ #3 [ 3102.991695] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 3102.992605] RIP: 0010:__list_del_entry_valid_or_report+0x4f/0xc0 [ 3102.993122] Code: 39 c2 74 56 48 8b 32 48 39 fe 75 62 48 8b 51 08 48 39 f2 75 73 b8 01 00 00 00 c3 48 89 fe 48 c7 c7 48 fd 0a 82 e8 41 0b ad ff <0f> 0b 31 c0 c3 48 89 fe 48 c7 c7 70 fd 0a 82 e8 2d 0b ad ff 0f 0b [ 3102.994615] RSP: 0018:ffff8881383e7710 EFLAGS: 00010286 [ 3102.995078] RAX: 0000000000000000 RBX: 0000000000000002 RCX: 0000000000000000 [ 3102.995670] RDX: 0000000000000001 RSI: ffff88885f89b640 RDI: ffff88885f89b640 [ 3102.997188] DEL flow 00000000be367878 on port 0 [ 3102.998594] RBP: dead000000000122 R08: 0000000000000000 R09: c0000000ffffdfff [ 3102.999604] R10: 0000000000000008 R11: ffff8881383e7598 R12: dead000000000100 [ 3103.000198] R13: 0000000000000002 R14: ffff888139110000 R15: ffff888101901240 [ 3103.000790] FS: 00007f424cde4700(0000) GS:ffff88885f880000(0000) knlGS:0000000000000000 [ 3103.001486] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3103.001986] CR2: 00007fd42e8dcb70 CR3: 000000011e68a003 CR4: 0000000000370ea0 [ 3103.002596] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 3103.003190] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 3103.003787] Call Trace: [ 3103.004055] <TASK> [ 3103.004297] ? __warn+0x7d/0x130 [ 3103.004623] ? __list_del_entry_valid_or_report+0x4f/0xc0 [ 3103.005094] ? report_bug+0xf1/0x1c0 [ 3103.005439] ? console_unlock+0x4a/0xd0 [ 3103.005806] ? handle_bug+0x3f/0x70 [ 3103.006149] ? exc_invalid_op+0x13/0x60 [ 3103.006531] ? asm_exc_invalid_op+0x16/0x20 [ 3103.007430] ? __list_del_entry_valid_or_report+0x4f/0xc0 [ 3103.007910] mlx5e_tc_del_fdb_peers_flow+0xcf/0x240 [mlx5_core] [ 3103.008463] mlx5e_tc_del_flow+0x46/0x270 [mlx5_core] [ 3103.008944] mlx5e_flow_put+0x26/0x50 [mlx5_core] [ 3103.009401] mlx5e_delete_flower+0x25f/0x380 [mlx5_core] [ 3103.009901] tc_setup_cb_destroy+0xab/0x180 [ 3103.010292] fl_hw_destroy_filter+0x99/0xc0 [cls_flower] [ 3103.010779] __fl_delete+0x2d4/0x2f0 [cls_flower] [ 3103.011207] fl_delete+0x36/0x80 [cls_flower] [ 3103.011614] tc_del_tfilter+0x56f/0x750 [ 3103.011982] rtnetlink_rcv_msg+0xff/0x3a0 [ 3103.012362] ? netlink_ack+0x1c7/0x4e0 [ 3103.012719] ? rtnl_calcit.isra.44+0x130/0x130 [ 3103.013134] netlink_rcv_skb+0x54/0x100 [ 3103.013533] netlink_unicast+0x1ca/0x2b0 [ 3103.013902] netlink_sendmsg+0x361/0x4d0 [ 3103.014269] __sock_sendmsg+0x38/0x60 [ 3103.014643] ____sys_sendmsg+0x1f2/0x200 [ 3103.015018] ? copy_msghdr_from_user+0x72/0xa0 [ 3103.015265] ___sys_sendmsg+0x87/0xd0 [ 3103.016608] ? copy_msghdr_from_user+0x72/0xa0 [ 3103.017014] ? ___sys_recvmsg+0x9b/0xd0 [ 3103.017381] ? ttwu_do_activate.isra.137+0x58/0x180 [ 3103.017821] ? wake_up_q+0x49/0x90 [ 3103.018157] ? futex_wake+0x137/0x160 [ 3103.018521] ? __sys_sendmsg+0x51/0x90 [ 3103.018882] __sys_sendmsg+0x51/0x90 [ 3103.019230] ? exit_to_user_mode_prepare+0x56/0x130 [ 3103.019670] do_syscall_64+0x3c/0x80 [ 3103.020017] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 3103.020469] RIP: 0033:0x7f4254811ef4 [ 3103.020816] Code: 89 f3 48 83 ec 10 48 89 7c 24 08 48 89 14 24 e8 42 eb ff ff 48 8b 14 24 41 89 c0 48 89 de 48 8b 7c 24 08 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 30 44 89 c7 48 89 04 24 e8 78 eb ff ff 48 8b [ 3103.022290] RSP: 002b:00007f424cdd9480 EFLAGS: 00000293 ORIG_RAX: 000000000000002e [ 3103.022970] RAX: ffffffffffffffda RBX: 00007f424cdd9510 RCX: 00007f4254811ef4 [ 3103.023564] RDX: 0000000000000000 RSI: 00007f424cdd9510 RDI: 0000000000000012 [ 3103.024158] RBP: 00007f424cdda238 R08: 0000000000000000 R09: 00007f41d801a4b0 [ 3103.024748] R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001 [ 3103.025341] R13: 00007f424cdd9510 R14: 00007f424cdda240 R15: 00007f424cdd99a0 [ 3103.025931] </TASK> [ 3103.026182] ---[ end trace 0000000000000000 ]--- [ 3103.027033] ------------[ cut here ]------------ Fixes: 9be6c21 ("net/mlx5e: Handle offloads flows per peer") Signed-off-by: Vlad Buslov <[email protected]> Reviewed-by: Mark Bloch <[email protected]> Signed-off-by: Saeed Mahameed <[email protected]>

Similar to a reported issue (check the commit b33fb5b ("net: qualcomm: rmnet: fix global oob in rmnet_policy"), my local fuzzer finds another global out-of-bounds read for policy ksmbd_nl_policy. See bug trace below: ================================================================== BUG: KASAN: global-out-of-bounds in validate_nla lib/nlattr.c:386 [inline] BUG: KASAN: global-out-of-bounds in __nla_validate_parse+0x24af/0x2750 lib/nlattr.c:600 Read of size 1 at addr ffffffff8f24b100 by task syz-executor.1/62810 CPU: 0 PID: 62810 Comm: syz-executor.1 Tainted: G N 6.1.0 #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x8b/0xb3 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:284 [inline] print_report+0x172/0x475 mm/kasan/report.c:395 kasan_report+0xbb/0x1c0 mm/kasan/report.c:495 validate_nla lib/nlattr.c:386 [inline] __nla_validate_parse+0x24af/0x2750 lib/nlattr.c:600 __nla_parse+0x3e/0x50 lib/nlattr.c:697 __nlmsg_parse include/net/netlink.h:748 [inline] genl_family_rcv_msg_attrs_parse.constprop.0+0x1b0/0x290 net/netlink/genetlink.c:565 genl_family_rcv_msg_doit+0xda/0x330 net/netlink/genetlink.c:734 genl_family_rcv_msg net/netlink/genetlink.c:833 [inline] genl_rcv_msg+0x441/0x780 net/netlink/genetlink.c:850 netlink_rcv_skb+0x14f/0x410 net/netlink/af_netlink.c:2540 genl_rcv+0x24/0x40 net/netlink/genetlink.c:861 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline] netlink_unicast+0x54e/0x800 net/netlink/af_netlink.c:1345 netlink_sendmsg+0x930/0xe50 net/netlink/af_netlink.c:1921 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0x154/0x190 net/socket.c:734 ____sys_sendmsg+0x6df/0x840 net/socket.c:2482 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2536 __sys_sendmsg+0xf3/0x1c0 net/socket.c:2565 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fdd66a8f359 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fdd65e00168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fdd66bbcf80 RCX: 00007fdd66a8f359 RDX: 0000000000000000 RSI: 0000000020000500 RDI: 0000000000000003 RBP: 00007fdd66ada493 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffc84b81aff R14: 00007fdd65e00300 R15: 0000000000022000 </TASK> The buggy address belongs to the variable: ksmbd_nl_policy+0x100/0xa80 The buggy address belongs to the physical page: page:0000000034f47940 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1ccc4b flags: 0x200000000001000(reserved|node=0|zone=2) raw: 0200000000001000 ffffea00073312c8 ffffea00073312c8 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffffffff8f24b000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffffff8f24b080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffffff8f24b100: f9 f9 f9 f9 00 00 f9 f9 f9 f9 f9 f9 00 00 07 f9 ^ ffffffff8f24b180: f9 f9 f9 f9 00 05 f9 f9 f9 f9 f9 f9 00 00 00 05 ffffffff8f24b200: f9 f9 f9 f9 00 00 03 f9 f9 f9 f9 f9 00 00 04 f9 ================================================================== To fix it, add a placeholder named __KSMBD_EVENT_MAX and let KSMBD_EVENT_MAX to be its original value - 1 according to what other netlink families do. Also change two sites that refer the KSMBD_EVENT_MAX to correct value. Cc: [email protected] Fixes: 0626e66 ("cifsd: add server handler for central processing and tranport layers") Signed-off-by: Lin Ma <[email protected]> Acked-by: Namjae Jeon <[email protected]> Signed-off-by: Steve French <[email protected]>

Many devices with a single alternate setting do not have a Valid Alternate Setting Control and validation performed by validate_sample_rate_table_v2v3() doesn't work on them and is not really needed. So check the presense of control before sending altsetting validation requests. MOTU Microbook IIc is suffering the most without this check. It takes up to 40 seconds to bootup due to how slow it switches sampling rates: [ 2659.164824] usb 3-2: New USB device found, idVendor=07fd, idProduct=0004, bcdDevice= 0.60 [ 2659.164827] usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 2659.164829] usb 3-2: Product: MicroBook IIc [ 2659.164830] usb 3-2: Manufacturer: MOTU [ 2659.166204] usb 3-2: Found last interface = 3 [ 2679.322298] usb 3-2: No valid sample rate available for 1:1, assuming a firmware bug [ 2679.322306] usb 3-2: 1:1: add audio endpoint 0x3 [ 2679.322321] usb 3-2: Creating new data endpoint #3 [ 2679.322552] usb 3-2: 1:1 Set sample rate 96000, clock 1 [ 2684.362250] usb 3-2: 2:1: cannot get freq (v2/v3): err -110 [ 2694.444700] usb 3-2: No valid sample rate available for 2:1, assuming a firmware bug [ 2694.444707] usb 3-2: 2:1: add audio endpoint 0x84 [ 2694.444721] usb 3-2: Creating new data endpoint #84 [ 2699.482103] usb 3-2: 2:1 Set sample rate 96000, clock 1 Signed-off-by: Alexander Tsoy <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Takashi Iwai <[email protected]>

Merge series from Jerome Brunet <[email protected]>: This patchset fixes 2 problems on TDM which both find a solution by properly implementing the .trigger() callback for the TDM backend. ATM, enabling the TDM formatters is done by the .prepare() callback because handling the formatter is slow due to necessary calls to CCF. The first problem affects the TDMIN. Because .prepare() is called on DPCM backend first, the formatter are started before the FIFOs and this may cause a random channel shifts if the TDMIN use multiple lanes with more than 2 slots per lanes. Using trigger() allows to set the FE/BE order, solving the problem. There has already been an attempt to fix this 3y ago [1] and reverted [2] It triggered a 'sleep in irq' error on the period IRQ. The solution is to just use the bottom half of threaded IRQ. This is patch #1. Patch #2 and #3 remain mostly the same as 3y ago. For TDMOUT, the problem is on pause. ATM pause only stops the FIFO and the TDMOUT just starves. When it does, it will actually repeat the last sample continuously. Depending on the platform, if there is no high-pass filter on the analog path, this may translate to a constant position of the speaker membrane. There is no audible glitch but it may damage the speaker coil. Properly stopping the TDMOUT in pause solves the problem. There is behaviour change associated with that fix. Clocks used to be continuous on pause because of the problem above. They will now be gated on pause by default, as they should. The last change introduce the proper support for continuous clocks, if needed. [1]: https://lore.kernel.org/linux-amlogic/[email protected] [2]: https://lore.kernel.org/linux-amlogic/[email protected]

Andrii Nakryiko says: ==================== Fix BPF multi-uprobe PID filtering logic It turns out that current implementation of multi-uprobe PID filtering logic is broken. It filters by thread, while the promise is filtering by process. Patch #1 fixes the logic trivially. The rest is testing and mitigations that are necessary for libbpf to not break users of USDT programs. v1->v2: - fix selftest in last patch (CI); - use semicolon in patch #3 (Jiri). ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 syzbot reports that nf_reinject() could be called without rcu_read_lock() when flushing pending packets at nfnetlink queue removal, from Eric Dumazet. Patch #2 flushes ipset list:set when canceling garbage collection to reference to other lists to fix a race, from Jozsef Kadlecsik. Patch #3 restores q-in-q matching with nft_payload by reverting f6ae9f1 ("netfilter: nft_payload: add C-VLAN support"). Patch #4 fixes vlan mangling in skbuff when vlan offload is present in skbuff, without this patch nft_payload corrupts packets in this case. Patch #5 fixes possible nul-deref in tproxy no IP address is found in netdevice, reported by syzbot and patch from Florian Westphal. Patch #6 removes a superfluous restriction which prevents loose fib lookups from input and forward hooks, from Eric Garver. My assessment is that patches #1, #2 and #5 address possible kernel crash, anything else in this batch fixes broken features. netfilter pull request 24-05-29 * tag 'nf-24-05-29' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: nft_fib: allow from forward/input without iif selector netfilter: tproxy: bail out if IP has been disabled on the device netfilter: nft_payload: skbuff vlan metadata mangle support netfilter: nft_payload: restore vlan q-in-q match support netfilter: ipset: Add list flush to cancel_gc netfilter: nfnetlink_queue: acquire rcu_read_lock() in instance_destroy_rcu() ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Paolo Abeni <[email protected]>

With commit c4cb231 ("iommu/amd: Add support for enable/disable IOPF") we are hitting below issue. This happens because in IOPF enablement path it holds spin lock with irq disable and then tries to take mutex lock. dmesg: ----- [ 0.938739] ============================= [ 0.938740] [ BUG: Invalid wait context ] [ 0.938742] 6.10.0-rc1+ #1 Not tainted [ 0.938745] ----------------------------- [ 0.938746] swapper/0/1 is trying to lock: [ 0.938748] ffffffff8c9f01d8 (&port_lock_key){....}-{3:3}, at: serial8250_console_write+0x78/0x4a0 [ 0.938767] other info that might help us debug this: [ 0.938768] context-{5:5} [ 0.938769] 7 locks held by swapper/0/1: [ 0.938772] #0: ffff888101a91310 (&group->mutex){+.+.}-{4:4}, at: bus_iommu_probe+0x70/0x160 [ 0.938790] #1: ffff888101d1f1b8 (&domain->lock){....}-{3:3}, at: amd_iommu_attach_device+0xa5/0x700 [ 0.938799] #2: ffff888101cc3d18 (&dev_data->lock){....}-{3:3}, at: amd_iommu_attach_device+0xc5/0x700 [ 0.938806] #3: ffff888100052830 (&iommu->lock){....}-{2:2}, at: amd_iommu_iopf_add_device+0x3f/0xa0 [ 0.938813] #4: ffffffff8945a340 (console_lock){+.+.}-{0:0}, at: _printk+0x48/0x50 [ 0.938822] #5: ffffffff8945a390 (console_srcu){....}-{0:0}, at: console_flush_all+0x58/0x4e0 [ 0.938867] #6: ffffffff82459f80 (console_owner){....}-{0:0}, at: console_flush_all+0x1f0/0x4e0 [ 0.938872] stack backtrace: [ 0.938874] CPU: 2 PID: 1 Comm: swapper/0 Not tainted 6.10.0-rc1+ #1 [ 0.938877] Hardware name: HP HP EliteBook 745 G3/807E, BIOS N73 Ver. 01.39 04/16/2019 Fix above issue by re-arranging code in attach device path: - move device PASID/IOPF enablement outside lock in AMD IOMMU driver. This is safe as core layer holds group->mutex lock before calling iommu_ops->attach_dev. Reported-by: Borislav Petkov <[email protected]> Reported-by: Mikhail Gavrilov <[email protected]> Reported-by: Chris Bainbridge <[email protected]> Fixes: c4cb231 ("iommu/amd: Add support for enable/disable IOPF") Tested-by: Borislav Petkov <[email protected]> Tested-by: Chris Bainbridge <[email protected]> Tested-by: Mikhail Gavrilov <[email protected]> Signed-off-by: Vasant Hegde <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Joerg Roedel <[email protected]>

…PLES event" This reverts commit 7d1405c. This causes segfaults in some cases, as reported by Milian: ``` sudo /usr/bin/perf record -z --call-graph dwarf -e cycles -e raw_syscalls:sys_enter ls ... [ perf record: Woken up 3 times to write data ] malloc(): invalid next size (unsorted) Aborted ``` Backtrace with GDB + debuginfod: ``` malloc(): invalid next size (unsorted) Thread 1 "perf" received signal SIGABRT, Aborted. __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44 Downloading source file /usr/src/debug/glibc/glibc/nptl/pthread_kill.c 44 return INTERNAL_SYSCALL_ERROR_P (ret) ? INTERNAL_SYSCALL_ERRNO (ret) : 0; (gdb) bt #0 __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44 #1 0x00007ffff6ea8eb3 in __pthread_kill_internal (threadid=<optimized out>, signo=6) at pthread_kill.c:78 #2 0x00007ffff6e50a30 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/ raise.c:26 #3 0x00007ffff6e384c3 in __GI_abort () at abort.c:79 #4 0x00007ffff6e39354 in __libc_message_impl (fmt=fmt@entry=0x7ffff6fc22ea "%s\n") at ../sysdeps/posix/libc_fatal.c:132 #5 0x00007ffff6eb3085 in malloc_printerr (str=str@entry=0x7ffff6fc5850 "malloc(): invalid next size (unsorted)") at malloc.c:5772 #6 0x00007ffff6eb657c in _int_malloc (av=av@entry=0x7ffff6ff6ac0 <main_arena>, bytes=bytes@entry=368) at malloc.c:4081 #7 0x00007ffff6eb877e in __libc_calloc (n=<optimized out>, elem_size=<optimized out>) at malloc.c:3754 #8 0x000055555569bdb6 in perf_session.do_write_header () #9 0x00005555555a373a in __cmd_record.constprop.0 () #10 0x00005555555a6846 in cmd_record () #11 0x000055555564db7f in run_builtin () #12 0x000055555558ed77 in main () ``` Valgrind memcheck: ``` ==45136== Invalid write of size 8 ==45136== at 0x2B38A5: perf_event__synthesize_id_sample (in /usr/bin/perf) ==45136== by 0x157069: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd ==45136== at 0x4849BF3: calloc (vg_replace_malloc.c:1675) ==45136== by 0x3574AB: zalloc (in /usr/bin/perf) ==45136== by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== ==45136== Syscall param write(buf) points to unaddressable byte(s) ==45136== at 0x575953D: __libc_write (write.c:26) ==45136== by 0x575953D: write (write.c:24) ==45136== by 0x35761F: ion (in /usr/bin/perf) ==45136== by 0x357778: writen (in /usr/bin/perf) ==45136== by 0x1548F7: record__write (in /usr/bin/perf) ==45136== by 0x15708A: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== Address 0x6a866a8 is 0 bytes after a block of size 40 alloc'd ==45136== at 0x4849BF3: calloc (vg_replace_malloc.c:1675) ==45136== by 0x3574AB: zalloc (in /usr/bin/perf) ==45136== by 0x1570E0: __cmd_record.constprop.0 (in /usr/bin/perf) ==45136== by 0x15A845: cmd_record (in /usr/bin/perf) ==45136== by 0x201B7E: run_builtin (in /usr/bin/perf) ==45136== by 0x142D76: main (in /usr/bin/perf) ==45136== ----- Closes: https://lore.kernel.org/linux-perf-users/23879991.0LEYPuXRzz@milian-workstation/ Reported-by: Milian Wolff <[email protected]> Tested-by: Milian Wolff <[email protected]> Cc: Adrian Hunter <[email protected]> Cc: Ian Rogers <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Kan Liang <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: [email protected] # 6.8+ Link: https://lore.kernel.org/lkml/Zl9ksOlHJHnKM70p@x1 Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

We have been seeing crashes on duplicate keys in btrfs_set_item_key_safe(): BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192) ------------[ cut here ]------------ kernel BUG at fs/btrfs/ctree.c:2620! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014 RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs] With the following stack trace: #0 btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4) #1 btrfs_drop_extents (fs/btrfs/file.c:411:4) #2 log_one_extent (fs/btrfs/tree-log.c:4732:9) #3 btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9) #4 btrfs_log_inode (fs/btrfs/tree-log.c:6626:9) #5 btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8) #6 btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8) #7 btrfs_sync_file (fs/btrfs/file.c:1933:8) #8 vfs_fsync_range (fs/sync.c:188:9) #9 vfs_fsync (fs/sync.c:202:9) #10 do_fsync (fs/sync.c:212:9) #11 __do_sys_fdatasync (fs/sync.c:225:9) #12 __se_sys_fdatasync (fs/sync.c:223:1) #13 __x64_sys_fdatasync (fs/sync.c:223:1) #14 do_syscall_x64 (arch/x86/entry/common.c:52:14) #15 do_syscall_64 (arch/x86/entry/common.c:83:7) #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121) So we're logging a changed extent from fsync, which is splitting an extent in the log tree. But this split part already exists in the tree, triggering the BUG(). This is the state of the log tree at the time of the crash, dumped with drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py) to get more details than btrfs_print_leaf() gives us: >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"]) leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610 leaf 33439744 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 7 transid 9 size 8192 nbytes 8473563889606862198 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 204 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417704.983333333 (2024-05-22 15:41:44) mtime 1716417704.983333333 (2024-05-22 15:41:44) otime 17592186044416.000000000 (559444-03-08 01:40:16) item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13 index 195 namelen 3 name: 193 item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 4096 ram 12288 extent compression 0 (none) item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 4096 nr 8192 item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 ... So the real problem happened earlier: notice that items 4 (4k-12k) and 5 (8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and item 5 starts at i_size. Here is the state of the filesystem tree at the time of the crash: >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0)) >>> print_extent_buffer(nodes[0]) leaf 30425088 level 0 items 184 generation 9 owner 5 leaf 30425088 flags 0x100000000000000 fs uuid e5bd3946-400c-4223-8923-190ef1f18677 chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da ... item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160 generation 7 transid 7 size 4096 nbytes 12288 block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0 sequence 6 flags 0x10(PREALLOC) atime 1716417703.220000000 (2024-05-22 15:41:43) ctime 1716417703.220000000 (2024-05-22 15:41:43) mtime 1716417703.220000000 (2024-05-22 15:41:43) otime 1716417703.220000000 (2024-05-22 15:41:43) item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13 index 195 namelen 3 name: 193 item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37 location key (0 UNKNOWN.0 0) type XATTR transid 7 data_len 1 name_len 6 name: user.a data a item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53 generation 9 type 1 (regular) extent data disk byte 303144960 nr 12288 extent data offset 0 nr 8192 ram 12288 extent compression 0 (none) item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53 generation 9 type 2 (prealloc) prealloc data disk byte 303144960 nr 12288 prealloc data offset 8192 nr 4096 Item 5 in the log tree corresponds to item 183 in the filesystem tree, but nothing matches item 4. Furthermore, item 183 is the last item in the leaf. btrfs_log_prealloc_extents() is responsible for logging prealloc extents beyond i_size. It first truncates any previously logged prealloc extents that start beyond i_size. Then, it walks the filesystem tree and copies the prealloc extent items to the log tree. If it hits the end of a leaf, then it calls btrfs_next_leaf(), which unlocks the tree and does another search. However, while the filesystem tree is unlocked, an ordered extent completion may modify the tree. In particular, it may insert an extent item that overlaps with an extent item that was already copied to the log tree. This may manifest in several ways depending on the exact scenario, including an EEXIST error that is silently translated to a full sync, overlapping items in the log tree, or this crash. This particular crash is triggered by the following sequence of events: - Initially, the file has i_size=4k, a regular extent from 0-4k, and a prealloc extent beyond i_size from 4k-12k. The prealloc extent item is the last item in its B-tree leaf. - The file is fsync'd, which copies its inode item and both extent items to the log tree. - An xattr is set on the file, which sets the BTRFS_INODE_COPY_EVERYTHING flag. - The range 4k-8k in the file is written using direct I/O. i_size is extended to 8k, but the ordered extent is still in flight. - The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this calls copy_inode_items_to_log(), which calls btrfs_log_prealloc_extents(). - btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the filesystem tree. Since it starts before i_size, it skips it. Since it is the last item in its B-tree leaf, it calls btrfs_next_leaf(). - btrfs_next_leaf() unlocks the path. - The ordered extent completion runs, which converts the 4k-8k part of the prealloc extent to written and inserts the remaining prealloc part from 8k-12k. - btrfs_next_leaf() does a search and finds the new prealloc extent 8k-12k. - btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into the log tree. Note that it overlaps with the 4k-12k prealloc extent that was copied to the log tree by the first fsync. - fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k extent that was written. - This tries to drop the range 4k-8k in the log tree, which requires adjusting the start of the 4k-12k prealloc extent in the log tree to 8k. - btrfs_set_item_key_safe() sees that there is already an extent starting at 8k in the log tree and calls BUG(). Fix this by detecting when we're about to insert an overlapping file extent item in the log tree and truncating the part that would overlap. CC: [email protected] # 6.1+ Reviewed-by: Filipe Manana <[email protected]> Signed-off-by: Omar Sandoval <[email protected]> Signed-off-by: David Sterba <[email protected]>

Use a dedicated mutex to guard kvm_usage_count to fix a potential deadlock on x86 due to a chain of locks and SRCU synchronizations. Translating the below lockdep splat, CPU1 #6 will wait on CPU0 #1, CPU0 #8 will wait on CPU2 #3, and CPU2 #7 will wait on CPU1 #4 (if there's a writer, due to the fairness of r/w semaphores). CPU0 CPU1 CPU2 1 lock(&kvm->slots_lock); 2 lock(&vcpu->mutex); 3 lock(&kvm->srcu); 4 lock(cpu_hotplug_lock); 5 lock(kvm_lock); 6 lock(&kvm->slots_lock); 7 lock(cpu_hotplug_lock); 8 sync(&kvm->srcu); Note, there are likely more potential deadlocks in KVM x86, e.g. the same pattern of taking cpu_hotplug_lock outside of kvm_lock likely exists with __kvmclock_cpufreq_notifier(), but actually triggering such deadlocks is beyond rare due to the combination of dependencies and timings involved. E.g. the cpufreq notifier is only used on older CPUs without a constant TSC, mucking with the NX hugepage mitigation while VMs are running is very uncommon, and doing so while also onlining/offlining a CPU (necessary to generate contention on cpu_hotplug_lock) would be even more unusual. ====================================================== WARNING: possible circular locking dependency detected 6.10.0-smp--c257535a0c9d-pip #330 Tainted: G S O ------------------------------------------------------ tee/35048 is trying to acquire lock: ff6a80eced71e0a8 (&kvm->slots_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x179/0x1e0 [kvm] but task is already holding lock: ffffffffc07abb08 (kvm_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x14a/0x1e0 [kvm] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (kvm_lock){+.+.}-{3:3}: __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 kvm_dev_ioctl+0x4fb/0xe50 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #2 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x2e/0xb0 static_key_slow_inc+0x16/0x30 kvm_lapic_set_base+0x6a/0x1c0 [kvm] kvm_set_apic_base+0x8f/0xe0 [kvm] kvm_set_msr_common+0x9ae/0xf80 [kvm] vmx_set_msr+0xa54/0xbe0 [kvm_intel] __kvm_set_msr+0xb6/0x1a0 [kvm] kvm_arch_vcpu_ioctl+0xeca/0x10c0 [kvm] kvm_vcpu_ioctl+0x485/0x5b0 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&kvm->srcu){.+.+}-{0:0}: __synchronize_srcu+0x44/0x1a0 synchronize_srcu_expedited+0x21/0x30 kvm_swap_active_memslots+0x110/0x1c0 [kvm] kvm_set_memslot+0x360/0x620 [kvm] __kvm_set_memory_region+0x27b/0x300 [kvm] kvm_vm_ioctl_set_memory_region+0x43/0x60 [kvm] kvm_vm_ioctl+0x295/0x650 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&kvm->slots_lock){+.+.}-{3:3}: __lock_acquire+0x15ef/0x2e30 lock_acquire+0xe0/0x260 __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 set_nx_huge_pages+0x179/0x1e0 [kvm] param_attr_store+0x93/0x100 module_attr_store+0x22/0x40 sysfs_kf_write+0x81/0xb0 kernfs_fop_write_iter+0x133/0x1d0 vfs_write+0x28d/0x380 ksys_write+0x70/0xe0 __x64_sys_write+0x1f/0x30 x64_sys_call+0x281b/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e Cc: Chao Gao <[email protected]> Fixes: 0bf5049 ("KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock") Cc: [email protected] Signed-off-by: Sean Christopherson <[email protected]>

…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 fixes insufficient sanitization of netlink attributes for the inner expression which can trigger nul-pointer dereference, from Davide Ornaghi. Patch #2 address a report that there is a race condition between namespace cleanup and the garbage collection of the list:set type. This patch resolves this issue with other minor issues as well, from Jozsef Kadlecsik. Patch #3 ip6_route_me_harder() ignores flowlabel/dsfield when ip dscp has been mangled, this unbreaks ip6 dscp set $v, from Florian Westphal. All of these patches address issues that are present in several releases. * tag 'nf-24-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: netfilter: Use flowlabel flow key when re-routing mangled packets netfilter: ipset: Fix race between namespace cleanup and gc in the list:set type netfilter: nft_inner: validate mandatory meta and payload ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

Nikolay Aleksandrov says: ==================== net: bridge: mst: fix suspicious rcu usage warning This set fixes a suspicious RCU usage warning triggered by syzbot[1] in the bridge's MST code. After I converted br_mst_set_state to RCU, I forgot to update the vlan group dereference helper. Fix it by using the proper helper, in order to do that we need to pass the vlan group which is already obtained correctly by the callers for their respective context. Patch 01 is a requirement for the fix in patch 02. Note I did consider rcu_dereference_rtnl() but the churn is much bigger and in every part of the bridge. We can do that as a cleanup in net-next. [1] https://syzkaller.appspot.com/bug?extid=9bbe2de1bc9d470eb5fe ============================= WARNING: suspicious RCU usage 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0 Not tainted ----------------------------- net/bridge/br_private.h:1599 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 4 locks held by syz-executor.1/5374: #0: ffff888022d50b18 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_lock include/linux/mmap_lock.h:144 [inline] #0: ffff888022d50b18 (&mm->mmap_lock){++++}-{3:3}, at: __mm_populate+0x1b0/0x460 mm/gup.c:2111 #1: ffffc90000a18c00 ((&p->forward_delay_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x650 kernel/time/timer.c:1789 #2: ffff88805fb2ccb8 (&br->lock){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #2: ffff88805fb2ccb8 (&br->lock){+.-.}-{2:2}, at: br_forward_delay_timer_expired+0x50/0x440 net/bridge/br_stp_timer.c:86 #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline] #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline] #3: ffffffff8e333fa0 (rcu_read_lock){....}-{1:2}, at: br_mst_set_state+0x171/0x7a0 net/bridge/br_mst.c:105 stack backtrace: CPU: 1 PID: 5374 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00235-g8a92980606e3 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 lockdep_rcu_suspicious+0x221/0x340 kernel/locking/lockdep.c:6712 nbp_vlan_group net/bridge/br_private.h:1599 [inline] br_mst_set_state+0x29e/0x7a0 net/bridge/br_mst.c:106 br_set_state+0x28a/0x7b0 net/bridge/br_stp.c:47 br_forward_delay_timer_expired+0x176/0x440 net/bridge/br_stp_timer.c:88 call_timer_fn+0x18e/0x650 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2417 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2428 run_timer_base kernel/time/timer.c:2437 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2447 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 __do_softirq kernel/softirq.c:588 [inline] invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf4/0x1c0 kernel/softirq.c:637 irq_exit_rcu+0x9/0x30 kernel/softirq.c:649 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 </IRQ> <TASK> ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

The syzbot fuzzer found that the interrupt-URB completion callback in the cdc-wdm driver was taking too long, and the driver's immediate resubmission of interrupt URBs with -EPROTO status combined with the dummy-hcd emulation to cause a CPU lockup: cdc_wdm 1-1:1.0: nonzero urb status received: -71 cdc_wdm 1-1:1.0: wdm_int_callback - 0 bytes watchdog: BUG: soft lockup - CPU#0 stuck for 26s! [syz-executor782:6625] CPU#0 Utilization every 4s during lockup: #1: 98% system, 0% softirq, 3% hardirq, 0% idle #2: 98% system, 0% softirq, 3% hardirq, 0% idle #3: 98% system, 0% softirq, 3% hardirq, 0% idle #4: 98% system, 0% softirq, 3% hardirq, 0% idle #5: 98% system, 1% softirq, 3% hardirq, 0% idle Modules linked in: irq event stamp: 73096 hardirqs last enabled at (73095): [<ffff80008037bc00>] console_emit_next_record kernel/printk/printk.c:2935 [inline] hardirqs last enabled at (73095): [<ffff80008037bc00>] console_flush_all+0x650/0xb74 kernel/printk/printk.c:2994 hardirqs last disabled at (73096): [<ffff80008af10b00>] __el1_irq arch/arm64/kernel/entry-common.c:533 [inline] hardirqs last disabled at (73096): [<ffff80008af10b00>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:551 softirqs last enabled at (73048): [<ffff8000801ea530>] softirq_handle_end kernel/softirq.c:400 [inline] softirqs last enabled at (73048): [<ffff8000801ea530>] handle_softirqs+0xa60/0xc34 kernel/softirq.c:582 softirqs last disabled at (73043): [<ffff800080020de8>] __do_softirq+0x14/0x20 kernel/softirq.c:588 CPU: 0 PID: 6625 Comm: syz-executor782 Tainted: G W 6.10.0-rc2-syzkaller-g8867bbd4a056 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Testing showed that the problem did not occur if the two error messages -- the first two lines above -- were removed; apparently adding material to the kernel log takes a surprisingly large amount of time. In any case, the best approach for preventing these lockups and to avoid spamming the log with thousands of error messages per second is to ratelimit the two dev_err() calls. Therefore we replace them with dev_err_ratelimited(). Signed-off-by: Alan Stern <[email protected]> Suggested-by: Greg KH <[email protected]> Reported-and-tested-by: [email protected] Closes: https://lore.kernel.org/linux-usb/[email protected]/ Reported-and-tested-by: [email protected] Closes: https://lore.kernel.org/linux-usb/[email protected]/ Fixes: 9908a32 ("USB: remove err() macro from usb class drivers") Link: https://lore.kernel.org/linux-usb/[email protected]/ Cc: [email protected] Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Greg Kroah-Hartman <[email protected]>

…git/netfilter/nf Pablo Neira Ayuso says: ==================== Netfilter fixes for net The following patchset contains Netfilter fixes for net: Patch #1 fixes the suspicious RCU usage warning that resulted from the recent fix for the race between namespace cleanup and gc in ipset left out checking the pernet exit phase when calling rcu_dereference_protected(), from Jozsef Kadlecsik. Patch #2 fixes incorrect input and output netdevice in SRv6 prerouting hooks, from Jianguo Wu. Patch #3 moves nf_hooks_lwtunnel sysctl toggle to the netfilter core. The connection tracking system is loaded on-demand, this ensures availability of this knob regardless. Patch #4-#5 adds selftests for SRv6 netfilter hooks also from Jianguo Wu. netfilter pull request 24-06-19 * tag 'nf-24-06-19' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf: selftests: add selftest for the SRv6 End.DX6 behavior with netfilter selftests: add selftest for the SRv6 End.DX4 behavior with netfilter netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core seg6: fix parameter passing when calling NF_HOOK() in End.DX4 and End.DX6 behaviors netfilter: ipset: Fix suspicious rcu_dereference_protected() ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Paolo Abeni <[email protected]>

…play During inode logging (and log replay too), we are holding a transaction handle and we often need to call btrfs_iget(), which will read an inode from its subvolume btree if it's not loaded in memory and that results in allocating an inode with GFP_KERNEL semantics at the btrfs_alloc_inode() callback - and this may recurse into the filesystem in case we are under memory pressure and attempt to commit the current transaction, resulting in a deadlock since the logging (or log replay) task is holding a transaction handle open. Syzbot reported this with the following stack traces: WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Not tainted ------------------------------------------------------ syz-executor.1/9919 is trying to acquire lock: ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:334 [inline] ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook mm/slub.c:3891 [inline] ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: slab_alloc_node mm/slub.c:3981 [inline] ffffffff8dd3aac0 (fs_reclaim){+.+.}-{0:0}, at: kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020 but task is already holding lock: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&ei->log_mutex){+.+.}-{3:3}: __mutex_lock_common kernel/locking/mutex.c:608 [inline] __mutex_lock+0x175/0x9c0 kernel/locking/mutex.c:752 btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481 btrfs_log_inode_parent+0x8cb/0x2a90 fs/btrfs/tree-log.c:7079 btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180 btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2794 [inline] btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705 new_sync_write fs/read_write.c:497 [inline] vfs_write+0x6b6/0x1140 fs/read_write.c:590 ksys_write+0x12f/0x260 fs/read_write.c:643 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}: join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315 start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700 btrfs_commit_super+0xa1/0x110 fs/btrfs/disk-io.c:4170 close_ctree+0xcb0/0xf90 fs/btrfs/disk-io.c:4324 generic_shutdown_super+0x159/0x3d0 fs/super.c:642 kill_anon_super+0x3a/0x60 fs/super.c:1226 btrfs_kill_super+0x3b/0x50 fs/btrfs/super.c:2096 deactivate_locked_super+0xbe/0x1a0 fs/super.c:473 deactivate_super+0xde/0x100 fs/super.c:506 cleanup_mnt+0x222/0x450 fs/namespace.c:1267 task_work_run+0x14e/0x250 kernel/task_work.c:180 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] exit_to_user_mode_loop kernel/entry/common.c:114 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x278/0x2a0 kernel/entry/common.c:218 __do_fast_syscall_32+0x80/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (btrfs_trans_num_writers){++++}-{0:0}: __lock_release kernel/locking/lockdep.c:5468 [inline] lock_release+0x33e/0x6c0 kernel/locking/lockdep.c:5774 percpu_up_read include/linux/percpu-rwsem.h:99 [inline] __sb_end_write include/linux/fs.h:1650 [inline] sb_end_intwrite include/linux/fs.h:1767 [inline] __btrfs_end_transaction+0x5ca/0x920 fs/btrfs/transaction.c:1071 btrfs_commit_inode_delayed_inode+0x228/0x330 fs/btrfs/delayed-inode.c:1301 btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x480 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 dput.part.0+0x4b1/0x9b0 fs/dcache.c:845 dput+0x1f/0x30 fs/dcache.c:835 ovl_stack_put+0x60/0x90 fs/overlayfs/util.c:132 ovl_destroy_inode+0xc6/0x190 fs/overlayfs/super.c:182 destroy_inode+0xc4/0x1b0 fs/inode.c:311 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 dentry_unlink_inode+0x295/0x480 fs/dcache.c:400 __dentry_kill+0x1d0/0x600 fs/dcache.c:603 shrink_kill fs/dcache.c:1048 [inline] shrink_dentry_list+0x140/0x5d0 fs/dcache.c:1075 prune_dcache_sb+0xeb/0x150 fs/dcache.c:1156 super_cache_scan+0x32a/0x550 fs/super.c:221 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab_memcg mm/shrinker.c:548 [inline] shrink_slab+0xa87/0x1310 mm/shrinker.c:626 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 -> #0 (fs_reclaim){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3801 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3891 [inline] slab_alloc_node mm/slub.c:3981 [inline] kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020 btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411 alloc_inode+0x5d/0x230 fs/inode.c:261 iget5_locked fs/inode.c:1235 [inline] iget5_locked+0x1c9/0x2c0 fs/inode.c:1228 btrfs_iget_locked fs/btrfs/inode.c:5590 [inline] btrfs_iget_path fs/btrfs/inode.c:5607 [inline] btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636 add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline] copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928 btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592 log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline] btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718 btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline] btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141 btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180 btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2794 [inline] btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705 do_iter_readv_writev+0x504/0x780 fs/read_write.c:741 vfs_writev+0x36f/0xde0 fs/read_write.c:971 do_pwritev+0x1b2/0x260 fs/read_write.c:1072 __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline] __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline] __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e other info that might help us debug this: Chain exists of: fs_reclaim --> btrfs_trans_num_extwriters --> &ei->log_mutex Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&ei->log_mutex); lock(btrfs_trans_num_extwriters); lock(&ei->log_mutex); lock(fs_reclaim); *** DEADLOCK *** 7 locks held by syz-executor.1/9919: #0: ffff88802be20420 (sb_writers#23){.+.+}-{0:0}, at: do_pwritev+0x1b2/0x260 fs/read_write.c:1072 #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: inode_lock include/linux/fs.h:791 [inline] #1: ffff888065c0f8f0 (&sb->s_type->i_mutex_key#33){++++}-{3:3}, at: btrfs_inode_lock+0xc8/0x110 fs/btrfs/inode.c:385 #2: ffff888065c0f778 (&ei->i_mmap_lock){++++}-{3:3}, at: btrfs_inode_lock+0xee/0x110 fs/btrfs/inode.c:388 #3: ffff88802be20610 (sb_internal#4){.+.+}-{0:0}, at: btrfs_sync_file+0x95b/0xe10 fs/btrfs/file.c:1952 #4: ffff8880546323f0 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290 #5: ffff888054632418 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x430/0xf40 fs/btrfs/transaction.c:290 #6: ffff88804b569358 (&ei->log_mutex){+.+.}-{3:3}, at: btrfs_log_inode+0x39c/0x4660 fs/btrfs/tree-log.c:6481 stack backtrace: CPU: 2 PID: 9919 Comm: syz-executor.1 Not tainted 6.10.0-rc2-syzkaller-00361-g061d1af7b030 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __fs_reclaim_acquire mm/page_alloc.c:3801 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3815 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3891 [inline] slab_alloc_node mm/slub.c:3981 [inline] kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4020 btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411 alloc_inode+0x5d/0x230 fs/inode.c:261 iget5_locked fs/inode.c:1235 [inline] iget5_locked+0x1c9/0x2c0 fs/inode.c:1228 btrfs_iget_locked fs/btrfs/inode.c:5590 [inline] btrfs_iget_path fs/btrfs/inode.c:5607 [inline] btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636 add_conflicting_inode fs/btrfs/tree-log.c:5657 [inline] copy_inode_items_to_log+0x1039/0x1e30 fs/btrfs/tree-log.c:5928 btrfs_log_inode+0xa48/0x4660 fs/btrfs/tree-log.c:6592 log_new_delayed_dentries fs/btrfs/tree-log.c:6363 [inline] btrfs_log_inode+0x27dd/0x4660 fs/btrfs/tree-log.c:6718 btrfs_log_all_parents fs/btrfs/tree-log.c:6833 [inline] btrfs_log_inode_parent+0x22ba/0x2a90 fs/btrfs/tree-log.c:7141 btrfs_log_dentry_safe+0x59/0x80 fs/btrfs/tree-log.c:7180 btrfs_sync_file+0x9c1/0xe10 fs/btrfs/file.c:1959 vfs_fsync_range+0x141/0x230 fs/sync.c:188 generic_write_sync include/linux/fs.h:2794 [inline] btrfs_do_write_iter+0x584/0x10c0 fs/btrfs/file.c:1705 do_iter_readv_writev+0x504/0x780 fs/read_write.c:741 vfs_writev+0x36f/0xde0 fs/read_write.c:971 do_pwritev+0x1b2/0x260 fs/read_write.c:1072 __do_compat_sys_pwritev2 fs/read_write.c:1218 [inline] __se_compat_sys_pwritev2 fs/read_write.c:1210 [inline] __ia32_compat_sys_pwritev2+0x121/0x1b0 fs/read_write.c:1210 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e RIP: 0023:0xf7334579 Code: b8 01 10 06 03 (...) RSP: 002b:00000000f5f265ac EFLAGS: 00000292 ORIG_RAX: 000000000000017b RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000200002c0 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Fix this by ensuring we are under a NOFS scope whenever we call btrfs_iget() during inode logging and log replay. Reported-by: [email protected] Link: https://lore.kernel.org/linux-btrfs/[email protected]/ Fixes: 712e36c ("btrfs: use GFP_KERNEL in btrfs_alloc_inode") Reviewed-by: Johannes Thumshirn <[email protected]> Reviewed-by: Josef Bacik <[email protected]> Reviewed-by: Qu Wenruo <[email protected]> Signed-off-by: Filipe Manana <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]>

The code in ocfs2_dio_end_io_write() estimates number of necessary transaction credits using ocfs2_calc_extend_credits(). This however does not take into account that the IO could be arbitrarily large and can contain arbitrary number of extents. Extent tree manipulations do often extend the current transaction but not in all of the cases. For example if we have only single block extents in the tree, ocfs2_mark_extent_written() will end up calling ocfs2_replace_extent_rec() all the time and we will never extend the current transaction and eventually exhaust all the transaction credits if the IO contains many single block extents. Once that happens a WARN_ON(jbd2_handle_buffer_credits(handle) <= 0) is triggered in jbd2_journal_dirty_metadata() and subsequently OCFS2 aborts in response to this error. This was actually triggered by one of our customers on a heavily fragmented OCFS2 filesystem. To fix the issue make sure the transaction always has enough credits for one extent insert before each call of ocfs2_mark_extent_written(). Heming Zhao said: ------ PANIC: "Kernel panic - not syncing: OCFS2: (device dm-1): panic forced after error" PID: xxx TASK: xxxx CPU: 5 COMMAND: "SubmitThread-CA" #0 machine_kexec at ffffffff8c069932 #1 __crash_kexec at ffffffff8c1338fa #2 panic at ffffffff8c1d69b9 #3 ocfs2_handle_error at ffffffffc0c86c0c [ocfs2] #4 __ocfs2_abort at ffffffffc0c88387 [ocfs2] #5 ocfs2_journal_dirty at ffffffffc0c51e98 [ocfs2] #6 ocfs2_split_extent at ffffffffc0c27ea3 [ocfs2] #7 ocfs2_change_extent_flag at ffffffffc0c28053 [ocfs2] #8 ocfs2_mark_extent_written at ffffffffc0c28347 [ocfs2] #9 ocfs2_dio_end_io_write at ffffffffc0c2bef9 [ocfs2] #10 ocfs2_dio_end_io at ffffffffc0c2c0f5 [ocfs2] #11 dio_complete at ffffffff8c2b9fa7 #12 do_blockdev_direct_IO at ffffffff8c2bc09f #13 ocfs2_direct_IO at ffffffffc0c2b653 [ocfs2] #14 generic_file_direct_write at ffffffff8c1dcf14 #15 __generic_file_write_iter at ffffffff8c1dd07b #16 ocfs2_file_write_iter at ffffffffc0c49f1f [ocfs2] #17 aio_write at ffffffff8c2cc72e #18 kmem_cache_alloc at ffffffff8c248dde #19 do_io_submit at ffffffff8c2ccada #20 do_syscall_64 at ffffffff8c004984 #21 entry_SYSCALL_64_after_hwframe at ffffffff8c8000ba Link: https://lkml.kernel.org/r/[email protected] Link: https://lkml.kernel.org/r/[email protected] Fixes: c15471f ("ocfs2: fix sparse file & data ordering issue in direct io") Signed-off-by: Jan Kara <[email protected]> Reviewed-by: Joseph Qi <[email protected]> Reviewed-by: Heming Zhao <[email protected]> Cc: Mark Fasheh <[email protected]> Cc: Joel Becker <[email protected]> Cc: Junxiao Bi <[email protected]> Cc: Changwei Ge <[email protected]> Cc: Gang He <[email protected]> Cc: Jun Piao <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]>

Bos can be put with multiple unrelated dma-resv locks held. But imported bos attempt to grab the bo dma-resv during dma-buf detach that typically happens during cleanup. That leads to lockde splats similar to the below and a potential ABBA deadlock. Fix this by always taking the delayed workqueue cleanup path for imported bos. Requesting stable fixes from when the Xe driver was introduced, since its usage of drm_exec and wide vm dma_resvs appear to be the first reliable trigger of this. [22982.116427] ============================================ [22982.116428] WARNING: possible recursive locking detected [22982.116429] 6.10.0-rc2+ #10 Tainted: G U W [22982.116430] -------------------------------------------- [22982.116430] glxgears:sh0/5785 is trying to acquire lock: [22982.116431] ffff8c2bafa539a8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: dma_buf_detach+0x3b/0xf0 [22982.116438] but task is already holding lock: [22982.116438] ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116442] other info that might help us debug this: [22982.116442] Possible unsafe locking scenario: [22982.116443] CPU0 [22982.116444] ---- [22982.116444] lock(reservation_ww_class_mutex); [22982.116445] lock(reservation_ww_class_mutex); [22982.116447] *** DEADLOCK *** [22982.116447] May be due to missing lock nesting notation [22982.116448] 5 locks held by glxgears:sh0/5785: [22982.116449] #0: ffff8c2d9aba58c8 (&xef->vm.lock){+.+.}-{3:3}, at: xe_file_close+0xde/0x1c0 [xe] [22982.116507] #1: ffff8c2e28cc8480 (&vm->lock){++++}-{3:3}, at: xe_vm_close_and_put+0x161/0x9b0 [xe] [22982.116578] #2: ffff8c2e31982970 (&val->lock){.+.+}-{3:3}, at: xe_validation_ctx_init+0x6d/0x70 [xe] [22982.116647] #3: ffffacdc469478a8 (reservation_ww_class_acquire){+.+.}-{0:0}, at: xe_vma_destroy_unlocked+0x7f/0xe0 [xe] [22982.116716] #4: ffff8c2d9aba6da8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: drm_exec_lock_obj+0x49/0x2b0 [drm_exec] [22982.116719] stack backtrace: [22982.116720] CPU: 8 PID: 5785 Comm: glxgears:sh0 Tainted: G U W 6.10.0-rc2+ #10 [22982.116721] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023 [22982.116723] Call Trace: [22982.116724] <TASK> [22982.116725] dump_stack_lvl+0x77/0xb0 [22982.116727] __lock_acquire+0x1232/0x2160 [22982.116730] lock_acquire+0xcb/0x2d0 [22982.116732] ? dma_buf_detach+0x3b/0xf0 [22982.116734] ? __lock_acquire+0x417/0x2160 [22982.116736] __ww_mutex_lock.constprop.0+0xd0/0x13b0 [22982.116738] ? dma_buf_detach+0x3b/0xf0 [22982.116741] ? dma_buf_detach+0x3b/0xf0 [22982.116743] ? ww_mutex_lock+0x2b/0x90 [22982.116745] ww_mutex_lock+0x2b/0x90 [22982.116747] dma_buf_detach+0x3b/0xf0 [22982.116749] drm_prime_gem_destroy+0x2f/0x40 [drm] [22982.116775] xe_ttm_bo_destroy+0x32/0x220 [xe] [22982.116818] ? __mutex_unlock_slowpath+0x3a/0x290 [22982.116821] drm_exec_unlock_all+0xa1/0xd0 [drm_exec] [22982.116823] drm_exec_fini+0x12/0xb0 [drm_exec] [22982.116824] xe_validation_ctx_fini+0x15/0x40 [xe] [22982.116892] xe_vma_destroy_unlocked+0xb1/0xe0 [xe] [22982.116959] xe_vm_close_and_put+0x41a/0x9b0 [xe] [22982.117025] ? xa_find+0xe3/0x1e0 [22982.117028] xe_file_close+0x10a/0x1c0 [xe] [22982.117074] drm_file_free+0x22a/0x280 [drm] [22982.117099] drm_release_noglobal+0x22/0x70 [drm] [22982.117119] __fput+0xf1/0x2d0 [22982.117122] task_work_run+0x59/0x90 [22982.117125] do_exit+0x330/0xb40 [22982.117127] do_group_exit+0x36/0xa0 [22982.117129] get_signal+0xbd2/0xbe0 [22982.117131] arch_do_signal_or_restart+0x3e/0x240 [22982.117134] syscall_exit_to_user_mode+0x1e7/0x290 [22982.117137] do_syscall_64+0xa1/0x180 [22982.117139] ? lock_acquire+0xcb/0x2d0 [22982.117140] ? __set_task_comm+0x28/0x1e0 [22982.117141] ? find_held_lock+0x2b/0x80 [22982.117144] ? __set_task_comm+0xe1/0x1e0 [22982.117145] ? lock_release+0xca/0x290 [22982.117147] ? __do_sys_prctl+0x245/0xab0 [22982.117149] ? lockdep_hardirqs_on_prepare+0xde/0x190 [22982.117150] ? syscall_exit_to_user_mode+0xb0/0x290 [22982.117152] ? do_syscall_64+0xa1/0x180 [22982.117154] ? __lock_acquire+0x417/0x2160 [22982.117155] ? reacquire_held_locks+0xd1/0x1f0 [22982.117156] ? do_user_addr_fault+0x30c/0x790 [22982.117158] ? lock_acquire+0xcb/0x2d0 [22982.117160] ? find_held_lock+0x2b/0x80 [22982.117162] ? do_user_addr_fault+0x357/0x790 [22982.117163] ? lock_release+0xca/0x290 [22982.117164] ? do_user_addr_fault+0x361/0x790 [22982.117166] ? trace_hardirqs_off+0x4b/0xc0 [22982.117168] ? clear_bhb_loop+0x45/0xa0 [22982.117170] ? clear_bhb_loop+0x45/0xa0 [22982.117172] ? clear_bhb_loop+0x45/0xa0 [22982.117174] entry_SYSCALL_64_after_hwframe+0x76/0x7e [22982.117176] RIP: 0033:0x7f943d267169 [22982.117192] Code: Unable to access opcode bytes at 0x7f943d26713f. [22982.117193] RSP: 002b:00007f9430bffc80 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [22982.117195] RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f943d267169 [22982.117196] RDX: 0000000000000000 RSI: 0000000000000189 RDI: 00005622f89579d0 [22982.117197] RBP: 00007f9430bffcb0 R08: 0000000000000000 R09: 00000000ffffffff [22982.117198] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [22982.117199] R13: 0000000000000000 R14: 0000000000000000 R15: 00005622f89579d0 [22982.117202] </TASK> Fixes: dd08ebf ("drm/xe: Introduce a new DRM driver for Intel GPUs") Cc: Christian König <[email protected]> Cc: Daniel Vetter <[email protected]> Cc: [email protected] Cc: [email protected] Cc: <[email protected]> # v6.8+ Signed-off-by: Thomas Hellström <[email protected]> Reviewed-by: Matthew Brost <[email protected]> Reviewed-by: Daniel Vetter <[email protected]> Reviewed-by: Christian König <[email protected]> Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

When putting an inode during extent map shrinking we're doing a standard iput() but that may take a long time in case the inode is dirty and we are doing the final iput that triggers eviction - the VFS will have to wait for writeback before calling the btrfs evict callback (see fs/inode.c:evict()). This slows down the task running the shrinker which may have been triggered while updating some tree for example, meaning locks are held as well as an open transaction handle. Also if the iput() ends up triggering eviction and the inode has no links anymore, then we trigger item truncation which requires flushing delayed items, space reservation to start a transaction and that may trigger the space reclaim task and wait for it, resulting in deadlocks in case the reclaim task needs for example to commit a transaction and the shrinker is being triggered from a path holding a transaction handle. Syzbot reported such a case with the following stack traces: ====================================================== WARNING: possible circular locking dependency detected 6.10.0-rc2-syzkaller-00010-g2ab795141095 #0 Not tainted ------------------------------------------------------ kswapd0/111 is trying to acquire lock: ffff88801eae4610 (sb_internal#3){.+.+}-{0:0}, at: btrfs_commit_inode_delayed_inode+0x110/0x330 fs/btrfs/delayed-inode.c:1275 but task is already holding lock: ffffffff8dd3a9a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xa88/0x1970 mm/vmscan.c:6924 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (fs_reclaim){+.+.}-{0:0}: __fs_reclaim_acquire mm/page_alloc.c:3783 [inline] fs_reclaim_acquire+0x102/0x160 mm/page_alloc.c:3797 might_alloc include/linux/sched/mm.h:334 [inline] slab_pre_alloc_hook mm/slub.c:3890 [inline] slab_alloc_node mm/slub.c:3980 [inline] kmem_cache_alloc_lru_noprof+0x58/0x2f0 mm/slub.c:4019 btrfs_alloc_inode+0x118/0xb20 fs/btrfs/inode.c:8411 alloc_inode+0x5d/0x230 fs/inode.c:261 iget5_locked fs/inode.c:1235 [inline] iget5_locked+0x1c9/0x2c0 fs/inode.c:1228 btrfs_iget_locked fs/btrfs/inode.c:5590 [inline] btrfs_iget_path fs/btrfs/inode.c:5607 [inline] btrfs_iget+0xfb/0x230 fs/btrfs/inode.c:5636 create_reloc_inode+0x403/0x820 fs/btrfs/relocation.c:3911 btrfs_relocate_block_group+0x471/0xe60 fs/btrfs/relocation.c:4114 btrfs_relocate_chunk+0x143/0x450 fs/btrfs/volumes.c:3373 __btrfs_balance fs/btrfs/volumes.c:4157 [inline] btrfs_balance+0x211a/0x3f00 fs/btrfs/volumes.c:4534 btrfs_ioctl_balance fs/btrfs/ioctl.c:3675 [inline] btrfs_ioctl+0x12ed/0x8290 fs/btrfs/ioctl.c:4742 __do_compat_sys_ioctl+0x2c3/0x330 fs/ioctl.c:1007 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #2 (btrfs_trans_num_extwriters){++++}-{0:0}: join_transaction+0x164/0xf40 fs/btrfs/transaction.c:315 start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700 btrfs_rebuild_free_space_tree+0xaa/0x480 fs/btrfs/free-space-tree.c:1323 btrfs_start_pre_rw_mount+0x218/0xf60 fs/btrfs/disk-io.c:2999 open_ctree+0x41ab/0x52e0 fs/btrfs/disk-io.c:3554 btrfs_fill_super fs/btrfs/super.c:946 [inline] btrfs_get_tree_super fs/btrfs/super.c:1863 [inline] btrfs_get_tree+0x11e9/0x1b90 fs/btrfs/super.c:2089 vfs_get_tree+0x8f/0x380 fs/super.c:1780 fc_mount+0x16/0xc0 fs/namespace.c:1125 btrfs_get_tree_subvol fs/btrfs/super.c:2052 [inline] btrfs_get_tree+0xa53/0x1b90 fs/btrfs/super.c:2090 vfs_get_tree+0x8f/0x380 fs/super.c:1780 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #1 (btrfs_trans_num_writers){++++}-{0:0}: join_transaction+0x148/0xf40 fs/btrfs/transaction.c:314 start_transaction+0x427/0x1a70 fs/btrfs/transaction.c:700 btrfs_rebuild_free_space_tree+0xaa/0x480 fs/btrfs/free-space-tree.c:1323 btrfs_start_pre_rw_mount+0x218/0xf60 fs/btrfs/disk-io.c:2999 open_ctree+0x41ab/0x52e0 fs/btrfs/disk-io.c:3554 btrfs_fill_super fs/btrfs/super.c:946 [inline] btrfs_get_tree_super fs/btrfs/super.c:1863 [inline] btrfs_get_tree+0x11e9/0x1b90 fs/btrfs/super.c:2089 vfs_get_tree+0x8f/0x380 fs/super.c:1780 fc_mount+0x16/0xc0 fs/namespace.c:1125 btrfs_get_tree_subvol fs/btrfs/super.c:2052 [inline] btrfs_get_tree+0xa53/0x1b90 fs/btrfs/super.c:2090 vfs_get_tree+0x8f/0x380 fs/super.c:1780 do_new_mount fs/namespace.c:3352 [inline] path_mount+0x6e1/0x1f10 fs/namespace.c:3679 do_mount fs/namespace.c:3692 [inline] __do_sys_mount fs/namespace.c:3898 [inline] __se_sys_mount fs/namespace.c:3875 [inline] __ia32_sys_mount+0x295/0x320 fs/namespace.c:3875 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e -> #0 (sb_internal#3){.+.+}-{0:0}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1655 [inline] sb_start_intwrite include/linux/fs.h:1838 [inline] start_transaction+0xbc1/0x1a70 fs/btrfs/transaction.c:694 btrfs_commit_inode_delayed_inode+0x110/0x330 fs/btrfs/delayed-inode.c:1275 btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 btrfs_scan_root fs/btrfs/extent_map.c:1118 [inline] btrfs_free_extent_maps+0xbd3/0x1320 fs/btrfs/extent_map.c:1189 super_cache_scan+0x409/0x550 fs/super.c:227 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 other info that might help us debug this: Chain exists of: sb_internal#3 --> btrfs_trans_num_extwriters --> fs_reclaim Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(btrfs_trans_num_extwriters); lock(fs_reclaim); rlock(sb_internal#3); *** DEADLOCK *** 2 locks held by kswapd0/111: #0: ffffffff8dd3a9a0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0xa88/0x1970 mm/vmscan.c:6924 #1: ffff88801eae40e0 (&type->s_umount_key#62){++++}-{3:3}, at: super_trylock_shared fs/super.c:562 [inline] #1: ffff88801eae40e0 (&type->s_umount_key#62){++++}-{3:3}, at: super_cache_scan+0x96/0x550 fs/super.c:196 stack backtrace: CPU: 0 PID: 111 Comm: kswapd0 Not tainted 6.10.0-rc2-syzkaller-00010-g2ab795141095 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3869 [inline] __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 percpu_down_read include/linux/percpu-rwsem.h:51 [inline] __sb_start_write include/linux/fs.h:1655 [inline] sb_start_intwrite include/linux/fs.h:1838 [inline] start_transaction+0xbc1/0x1a70 fs/btrfs/transaction.c:694 btrfs_commit_inode_delayed_inode+0x110/0x330 fs/btrfs/delayed-inode.c:1275 btrfs_evict_inode+0x960/0xe80 fs/btrfs/inode.c:5291 evict+0x2ed/0x6c0 fs/inode.c:667 iput_final fs/inode.c:1741 [inline] iput.part.0+0x5a8/0x7f0 fs/inode.c:1767 iput+0x5c/0x80 fs/inode.c:1757 btrfs_scan_root fs/btrfs/extent_map.c:1118 [inline] btrfs_free_extent_maps+0xbd3/0x1320 fs/btrfs/extent_map.c:1189 super_cache_scan+0x409/0x550 fs/super.c:227 do_shrink_slab+0x44f/0x11c0 mm/shrinker.c:435 shrink_slab+0x18a/0x1310 mm/shrinker.c:662 shrink_one+0x493/0x7c0 mm/vmscan.c:4790 shrink_many mm/vmscan.c:4851 [inline] lru_gen_shrink_node+0x89f/0x1750 mm/vmscan.c:4951 shrink_node mm/vmscan.c:5910 [inline] kswapd_shrink_node mm/vmscan.c:6720 [inline] balance_pgdat+0x1105/0x1970 mm/vmscan.c:6911 kswapd+0x5ea/0xbf0 mm/vmscan.c:7180 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 </TASK> So fix this by using btrfs_add_delayed_iput() so that the final iput is delegated to the cleaner kthread. Link: https://lore.kernel.org/linux-btrfs/[email protected]/ Reported-by: [email protected] Fixes: 956a17d ("btrfs: add a shrinker for extent maps") Reviewed-by: Josef Bacik <[email protected]> Signed-off-by: Filipe Manana <[email protected]> Reviewed-by: David Sterba <[email protected]> Signed-off-by: David Sterba <[email protected]>

Use a dedicated mutex to guard kvm_usage_count to fix a potential deadlock on x86 due to a chain of locks and SRCU synchronizations. Translating the below lockdep splat, CPU1 #6 will wait on CPU0 #1, CPU0 #8 will wait on CPU2 #3, and CPU2 #7 will wait on CPU1 #4 (if there's a writer, due to the fairness of r/w semaphores). CPU0 CPU1 CPU2 1 lock(&kvm->slots_lock); 2 lock(&vcpu->mutex); 3 lock(&kvm->srcu); 4 lock(cpu_hotplug_lock); 5 lock(kvm_lock); 6 lock(&kvm->slots_lock); 7 lock(cpu_hotplug_lock); 8 sync(&kvm->srcu); Note, there are likely more potential deadlocks in KVM x86, e.g. the same pattern of taking cpu_hotplug_lock outside of kvm_lock likely exists with __kvmclock_cpufreq_notifier(), but actually triggering such deadlocks is beyond rare due to the combination of dependencies and timings involved. E.g. the cpufreq notifier is only used on older CPUs without a constant TSC, mucking with the NX hugepage mitigation while VMs are running is very uncommon, and doing so while also onlining/offlining a CPU (necessary to generate contention on cpu_hotplug_lock) would be even more unusual. ====================================================== WARNING: possible circular locking dependency detected 6.10.0-smp--c257535a0c9d-pip #330 Tainted: G S O ------------------------------------------------------ tee/35048 is trying to acquire lock: ff6a80eced71e0a8 (&kvm->slots_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x179/0x1e0 [kvm] but task is already holding lock: ffffffffc07abb08 (kvm_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x14a/0x1e0 [kvm] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (kvm_lock){+.+.}-{3:3}: __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 kvm_dev_ioctl+0x4fb/0xe50 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #2 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x2e/0xb0 static_key_slow_inc+0x16/0x30 kvm_lapic_set_base+0x6a/0x1c0 [kvm] kvm_set_apic_base+0x8f/0xe0 [kvm] kvm_set_msr_common+0x9ae/0xf80 [kvm] vmx_set_msr+0xa54/0xbe0 [kvm_intel] __kvm_set_msr+0xb6/0x1a0 [kvm] kvm_arch_vcpu_ioctl+0xeca/0x10c0 [kvm] kvm_vcpu_ioctl+0x485/0x5b0 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&kvm->srcu){.+.+}-{0:0}: __synchronize_srcu+0x44/0x1a0 synchronize_srcu_expedited+0x21/0x30 kvm_swap_active_memslots+0x110/0x1c0 [kvm] kvm_set_memslot+0x360/0x620 [kvm] __kvm_set_memory_region+0x27b/0x300 [kvm] kvm_vm_ioctl_set_memory_region+0x43/0x60 [kvm] kvm_vm_ioctl+0x295/0x650 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&kvm->slots_lock){+.+.}-{3:3}: __lock_acquire+0x15ef/0x2e30 lock_acquire+0xe0/0x260 __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 set_nx_huge_pages+0x179/0x1e0 [kvm] param_attr_store+0x93/0x100 module_attr_store+0x22/0x40 sysfs_kf_write+0x81/0xb0 kernfs_fop_write_iter+0x133/0x1d0 vfs_write+0x28d/0x380 ksys_write+0x70/0xe0 __x64_sys_write+0x1f/0x30 x64_sys_call+0x281b/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e Cc: Chao Gao <[email protected]> Fixes: 0bf5049 ("KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock") Cc: [email protected] Signed-off-by: Sean Christopherson <[email protected]>

Use a dedicated mutex to guard kvm_usage_count to fix a potential deadlock on x86 due to a chain of locks and SRCU synchronizations. Translating the below lockdep splat, CPU1 #6 will wait on CPU0 #1, CPU0 #8 will wait on CPU2 #3, and CPU2 #7 will wait on CPU1 #4 (if there's a writer, due to the fairness of r/w semaphores). CPU0 CPU1 CPU2 1 lock(&kvm->slots_lock); 2 lock(&vcpu->mutex); 3 lock(&kvm->srcu); 4 lock(cpu_hotplug_lock); 5 lock(kvm_lock); 6 lock(&kvm->slots_lock); 7 lock(cpu_hotplug_lock); 8 sync(&kvm->srcu); Note, there are likely more potential deadlocks in KVM x86, e.g. the same pattern of taking cpu_hotplug_lock outside of kvm_lock likely exists with __kvmclock_cpufreq_notifier(), but actually triggering such deadlocks is beyond rare due to the combination of dependencies and timings involved. E.g. the cpufreq notifier is only used on older CPUs without a constant TSC, mucking with the NX hugepage mitigation while VMs are running is very uncommon, and doing so while also onlining/offlining a CPU (necessary to generate contention on cpu_hotplug_lock) would be even more unusual. ====================================================== WARNING: possible circular locking dependency detected 6.10.0-smp--c257535a0c9d-pip #330 Tainted: G S O ------------------------------------------------------ tee/35048 is trying to acquire lock: ff6a80eced71e0a8 (&kvm->slots_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x179/0x1e0 [kvm] but task is already holding lock: ffffffffc07abb08 (kvm_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x14a/0x1e0 [kvm] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (kvm_lock){+.+.}-{3:3}: __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 kvm_dev_ioctl+0x4fb/0xe50 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #2 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x2e/0xb0 static_key_slow_inc+0x16/0x30 kvm_lapic_set_base+0x6a/0x1c0 [kvm] kvm_set_apic_base+0x8f/0xe0 [kvm] kvm_set_msr_common+0x9ae/0xf80 [kvm] vmx_set_msr+0xa54/0xbe0 [kvm_intel] __kvm_set_msr+0xb6/0x1a0 [kvm] kvm_arch_vcpu_ioctl+0xeca/0x10c0 [kvm] kvm_vcpu_ioctl+0x485/0x5b0 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&kvm->srcu){.+.+}-{0:0}: __synchronize_srcu+0x44/0x1a0 synchronize_srcu_expedited+0x21/0x30 kvm_swap_active_memslots+0x110/0x1c0 [kvm] kvm_set_memslot+0x360/0x620 [kvm] __kvm_set_memory_region+0x27b/0x300 [kvm] kvm_vm_ioctl_set_memory_region+0x43/0x60 [kvm] kvm_vm_ioctl+0x295/0x650 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&kvm->slots_lock){+.+.}-{3:3}: __lock_acquire+0x15ef/0x2e30 lock_acquire+0xe0/0x260 __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 set_nx_huge_pages+0x179/0x1e0 [kvm] param_attr_store+0x93/0x100 module_attr_store+0x22/0x40 sysfs_kf_write+0x81/0xb0 kernfs_fop_write_iter+0x133/0x1d0 vfs_write+0x28d/0x380 ksys_write+0x70/0xe0 __x64_sys_write+0x1f/0x30 x64_sys_call+0x281b/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e Cc: Chao Gao <[email protected]> Fixes: 0bf5049 ("KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock") Cc: [email protected] Signed-off-by: Sean Christopherson <[email protected]> Acked-by: Kai Huang <[email protected]> Reviewed-by: Kai Huang <[email protected]> Message-ID: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>

Use a dedicated mutex to guard kvm_usage_count to fix a potential deadlock on x86 due to a chain of locks and SRCU synchronizations. Translating the below lockdep splat, CPU1 #6 will wait on CPU0 #1, CPU0 #8 will wait on CPU2 #3, and CPU2 #7 will wait on CPU1 #4 (if there's a writer, due to the fairness of r/w semaphores). CPU0 CPU1 CPU2 1 lock(&kvm->slots_lock); 2 lock(&vcpu->mutex); 3 lock(&kvm->srcu); 4 lock(cpu_hotplug_lock); 5 lock(kvm_lock); 6 lock(&kvm->slots_lock); 7 lock(cpu_hotplug_lock); 8 sync(&kvm->srcu); Note, there are likely more potential deadlocks in KVM x86, e.g. the same pattern of taking cpu_hotplug_lock outside of kvm_lock likely exists with __kvmclock_cpufreq_notifier(): cpuhp_cpufreq_online() | -> cpufreq_online() | -> cpufreq_gov_performance_limits() | -> __cpufreq_driver_target() | -> __target_index() | -> cpufreq_freq_transition_begin() | -> cpufreq_notify_transition() | -> ... __kvmclock_cpufreq_notifier() But, actually triggering such deadlocks is beyond rare due to the combination of dependencies and timings involved. E.g. the cpufreq notifier is only used on older CPUs without a constant TSC, mucking with the NX hugepage mitigation while VMs are running is very uncommon, and doing so while also onlining/offlining a CPU (necessary to generate contention on cpu_hotplug_lock) would be even more unusual. The most robust solution to the general cpu_hotplug_lock issue is likely to switch vm_list to be an RCU-protected list, e.g. so that x86's cpufreq notifier doesn't to take kvm_lock. For now, settle for fixing the most blatant deadlock, as switching to an RCU-protected list is a much more involved change, but add a comment in locking.rst to call out that care needs to be taken when walking holding kvm_lock and walking vm_list. ====================================================== WARNING: possible circular locking dependency detected 6.10.0-smp--c257535a0c9d-pip #330 Tainted: G S O ------------------------------------------------------ tee/35048 is trying to acquire lock: ff6a80eced71e0a8 (&kvm->slots_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x179/0x1e0 [kvm] but task is already holding lock: ffffffffc07abb08 (kvm_lock){+.+.}-{3:3}, at: set_nx_huge_pages+0x14a/0x1e0 [kvm] which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (kvm_lock){+.+.}-{3:3}: __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 kvm_dev_ioctl+0x4fb/0xe50 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #2 (cpu_hotplug_lock){++++}-{0:0}: cpus_read_lock+0x2e/0xb0 static_key_slow_inc+0x16/0x30 kvm_lapic_set_base+0x6a/0x1c0 [kvm] kvm_set_apic_base+0x8f/0xe0 [kvm] kvm_set_msr_common+0x9ae/0xf80 [kvm] vmx_set_msr+0xa54/0xbe0 [kvm_intel] __kvm_set_msr+0xb6/0x1a0 [kvm] kvm_arch_vcpu_ioctl+0xeca/0x10c0 [kvm] kvm_vcpu_ioctl+0x485/0x5b0 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #1 (&kvm->srcu){.+.+}-{0:0}: __synchronize_srcu+0x44/0x1a0 synchronize_srcu_expedited+0x21/0x30 kvm_swap_active_memslots+0x110/0x1c0 [kvm] kvm_set_memslot+0x360/0x620 [kvm] __kvm_set_memory_region+0x27b/0x300 [kvm] kvm_vm_ioctl_set_memory_region+0x43/0x60 [kvm] kvm_vm_ioctl+0x295/0x650 [kvm] __se_sys_ioctl+0x7b/0xd0 __x64_sys_ioctl+0x21/0x30 x64_sys_call+0x15d0/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e -> #0 (&kvm->slots_lock){+.+.}-{3:3}: __lock_acquire+0x15ef/0x2e30 lock_acquire+0xe0/0x260 __mutex_lock+0x6a/0xb40 mutex_lock_nested+0x1f/0x30 set_nx_huge_pages+0x179/0x1e0 [kvm] param_attr_store+0x93/0x100 module_attr_store+0x22/0x40 sysfs_kf_write+0x81/0xb0 kernfs_fop_write_iter+0x133/0x1d0 vfs_write+0x28d/0x380 ksys_write+0x70/0xe0 __x64_sys_write+0x1f/0x30 x64_sys_call+0x281b/0x2e60 do_syscall_64+0x83/0x160 entry_SYSCALL_64_after_hwframe+0x76/0x7e Cc: Chao Gao <[email protected]> Fixes: 0bf5049 ("KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock") Cc: [email protected] Reviewed-by: Kai Huang <[email protected]> Acked-by: Kai Huang <[email protected]> Tested-by: Farrah Chen <[email protected]> Signed-off-by: Sean Christopherson <[email protected]> Message-ID: <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>

Syzkaller reported a lockdep splat: ============================================ WARNING: possible recursive locking detected 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Not tainted -------------------------------------------- syz-executor364/5113 is trying to acquire lock: ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff8880449f1958 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328 but task is already holding lock: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(k-slock-AF_INET); lock(k-slock-AF_INET); *** DEADLOCK *** May be due to missing lock nesting notation 7 locks held by syz-executor364/5113: #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline] #0: ffff8880449f0e18 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x153/0x1b10 net/mptcp/protocol.c:1806 #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1607 [inline] #1: ffff88803fe39ad8 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg_fastopen+0x11f/0x530 net/mptcp/protocol.c:1727 #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #2: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: __ip_queue_xmit+0x5f/0x1b80 net/ipv4/ip_output.c:470 #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #3: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1390 net/ipv4/ip_output.c:228 #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: local_lock_acquire include/linux/local_lock_internal.h:29 [inline] #4: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: process_backlog+0x33b/0x15b0 net/core/dev.c:6104 #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline] #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #5: ffffffff8e938320 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0x230/0x5f0 net/ipv4/ip_input.c:232 #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] #6: ffff88803fe3cb58 (k-slock-AF_INET){+.-.}-{2:2}, at: sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328 stack backtrace: CPU: 0 UID: 0 PID: 5113 Comm: syz-executor364 Not tainted 6.11.0-rc6-syzkaller-00019-g67784a74e258 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: <IRQ> __dump_stack lib/dump_stack.c:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 check_deadlock kernel/locking/lockdep.c:3061 [inline] validate_chain+0x15d3/0x5900 kernel/locking/lockdep.c:3855 __lock_acquire+0x137a/0x2040 kernel/locking/lockdep.c:5142 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] sk_clone_lock+0x2cd/0xf40 net/core/sock.c:2328 mptcp_sk_clone_init+0x32/0x13c0 net/mptcp/protocol.c:3279 subflow_syn_recv_sock+0x931/0x1920 net/mptcp/subflow.c:874 tcp_check_req+0xfe4/0x1a20 net/ipv4/tcp_minisocks.c:853 tcp_v4_rcv+0x1c3e/0x37f0 net/ipv4/tcp_ipv4.c:2267 ip_protocol_deliver_rcu+0x22e/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x341/0x5f0 net/ipv4/ip_input.c:233 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 NF_HOOK+0x3a4/0x450 include/linux/netfilter.h:314 __netif_receive_skb_one_core net/core/dev.c:5661 [inline] __netif_receive_skb+0x2bf/0x650 net/core/dev.c:5775 process_backlog+0x662/0x15b0 net/core/dev.c:6108 __napi_poll+0xcb/0x490 net/core/dev.c:6772 napi_poll net/core/dev.c:6841 [inline] net_rx_action+0x89b/0x1240 net/core/dev.c:6963 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 </IRQ> <TASK> __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:908 [inline] __dev_queue_xmit+0x1763/0x3e90 net/core/dev.c:4450 dev_queue_xmit include/linux/netdevice.h:3105 [inline] neigh_hh_output include/net/neighbour.h:526 [inline] neigh_output include/net/neighbour.h:540 [inline] ip_finish_output2+0xd41/0x1390 net/ipv4/ip_output.c:235 ip_local_out net/ipv4/ip_output.c:129 [inline] __ip_queue_xmit+0x118c/0x1b80 net/ipv4/ip_output.c:535 __tcp_transmit_skb+0x2544/0x3b30 net/ipv4/tcp_output.c:1466 tcp_rcv_synsent_state_process net/ipv4/tcp_input.c:6542 [inline] tcp_rcv_state_process+0x2c32/0x4570 net/ipv4/tcp_input.c:6729 tcp_v4_do_rcv+0x77d/0xc70 net/ipv4/tcp_ipv4.c:1934 sk_backlog_rcv include/net/sock.h:1111 [inline] __release_sock+0x214/0x350 net/core/sock.c:3004 release_sock+0x61/0x1f0 net/core/sock.c:3558 mptcp_sendmsg_fastopen+0x1ad/0x530 net/mptcp/protocol.c:1733 mptcp_sendmsg+0x1884/0x1b10 net/mptcp/protocol.c:1812 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x1a6/0x270 net/socket.c:745 ____sys_sendmsg+0x525/0x7d0 net/socket.c:2597 ___sys_sendmsg net/socket.c:2651 [inline] __sys_sendmmsg+0x3b2/0x740 net/socket.c:2737 __do_sys_sendmmsg net/socket.c:2766 [inline] __se_sys_sendmmsg net/socket.c:2763 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2763 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f04fb13a6b9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 01 1a 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd651f42d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f04fb13a6b9 RDX: 0000000000000001 RSI: 0000000020000d00 RDI: 0000000000000004 RBP: 00007ffd651f4310 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000020000080 R11: 0000000000000246 R12: 00000000000f4240 R13: 00007f04fb187449 R14: 00007ffd651f42f4 R15: 00007ffd651f4300 </TASK> As noted by Cong Wang, the splat is false positive, but the code path leading to the report is an unexpected one: a client is attempting an MPC handshake towards the in-kernel listener created by the in-kernel PM for a port based signal endpoint. Such connection will be never accepted; many of them can make the listener queue full and preventing the creation of MPJ subflow via such listener - its intended role. Explicitly detect this scenario at initial-syn time and drop the incoming MPC request. Fixes: 1729cf1 ("mptcp: create the listening socket for new port") Cc: [email protected] Reported-by: [email protected] Closes: https://syzkaller.appspot.com/bug?extid=f4aacdfef2c6a6529c3e Cc: Cong Wang <[email protected]> Signed-off-by: Paolo Abeni <[email protected]> Reviewed-by: Matthieu Baerts (NGI0) <[email protected]> Reviewed-by: Mat Martineau <[email protected]> Signed-off-by: Matthieu Baerts (NGI0) <[email protected]> Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

…/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 6.12, take #3 - Stop wasting space in the HYP idmap, as we are dangerously close to the 4kB limit, and this has already exploded in -next - Fix another race in vgic_init() - Fix a UBSAN error when faking the cache topology with MTE enabled

Hou Tao says: ==================== The patch set fixes several issues in bits iterator. Patch #1 fixes the kmemleak problem of bits iterator. Patch #2~#3 fix the overflow problem of nr_bits. Patch #4 fixes the potential stack corruption when bits iterator is used on 32-bit host. Patch #5 adds more test cases for bits iterator. Please see the individual patches for more details. And comments are always welcome. --- v4: * patch #1: add ack from Yafang * patch #3: revert code-churn like changes: (1) compute nr_bytes and nr_bits before the check of nr_words. (2) use nr_bits == 64 to check for single u64, preventing build warning on 32-bit hosts. * patch #4: use "BITS_PER_LONG == 32" instead of "!defined(CONFIG_64BIT)" v3: https://lore.kernel.org/bpf/[email protected]/T/#t * split the bits-iterator related patches from "Misc fixes for bpf" patch set * patch #1: use "!nr_bits || bits >= nr_bits" to stop the iteration * patch #2: add a new helper for the overflow problem * patch #3: decrease the limitation from 512 to 511 and check whether nr_bytes is too large for bpf memory allocator explicitly * patch #5: add two more test cases for bit iterator v2: http://lore.kernel.org/bpf/[email protected] ==================== Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Alexei Starovoitov <[email protected]>

Petr Machata says: ==================== mlxsw: Fixes In this patchset: - Tx header should be pushed for each packet which is transmitted via Spectrum ASICs. Patch #1 adds a missing call to skb_cow_head() to make sure that there is both enough room to push the Tx header and that the SKB header is not cloned and can be modified. - Commit b5b60bb ("mlxsw: pci: Use page pool for Rx buffers allocation") converted mlxsw to use page pool for Rx buffers allocation. Sync for CPU and for device should be done for Rx pages. In patches #2 and #3, add the missing calls to sync pages for, respectively, CPU and the device. - Patch #4 then fixes a bug to IPv6 GRE forwarding offload. Patch #5 adds a generic forwarding test that fails with mlxsw ports prior to the fix. ==================== Link: https://patch.msgid.link/[email protected] Signed-off-by: Jakub Kicinski <[email protected]>

Intel TDX protects guest VM's from malicious host and certain physical attacks. TDX introduces a new operation mode, Secure Arbitration Mode (SEAM) to isolate and protect guest VM's. A TDX guest VM runs in SEAM and, unlike VMX, direct control and interaction with the guest by the host VMM is not possible. Instead, Intel TDX Module, which also runs in SEAM, provides a SEAMCALL API. The SEAMCALL that provides the ability to enter a guest is TDH.VP.ENTER. The TDX Module processes TDH.VP.ENTER, and enters the guest via VMX VMLAUNCH/VMRESUME instructions. When a guest VM-exit requires host VMM interaction, the TDH.VP.ENTER SEAMCALL returns to the host VMM (KVM). Add tdh_vp_enter() to wrap the SEAMCALL invocation of TDH.VP.ENTER. TDH.VP.ENTER is different from other SEAMCALLS in several ways: - it may take some time to return as the guest executes - it uses more arguments - after it returns some host state may need to be restored TDH.VP.ENTER arguments are passed through General Purpose Registers (GPRs). For the special case of the TD guest invoking TDG.VP.VMCALL, nearly any GPR can be used, as well as XMM0 to XMM15. Notably, RBP is not used, and Linux mandates the TDX Module feature NO_RBP_MOD, which is enforced elsewhere. Additionally, XMM registers are not required for the existing Guest Hypervisor Communication Interface and are handled by existing KVM code should they be modified by the guest. There are 2 input formats and 5 output formats for TDH.VP.ENTER arguments. Input #1 : Initial entry or following a previous async. TD Exit Input #2 : Following a previous TDCALL(TDG.VP.VMCALL) Output #1 : On Error (No TD Entry) Output #2 : Async. Exits with a VMX Architectural Exit Reason Output #3 : Async. Exits with a non-VMX TD Exit Status Output #4 : Async. Exits with Cross-TD Exit Details Output #5 : On TDCALL(TDG.VP.VMCALL) Currently, to keep things simple, the wrapper function does not attempt to support different formats, and just passes all the GPRs that could be used. The GPR values are held by KVM in the area set aside for guest GPRs. KVM code uses the guest GPR area (vcpu->arch.regs[]) to set up for or process results of tdh_vp_enter(). Therefore changing tdh_vp_enter() to use more complex argument formats would also alter the way KVM code interacts with tdh_vp_enter(). Signed-off-by: Kai Huang <[email protected]> --- -Kai: - This is not nice, but for now have no clue on improvement.

Intel TDX protects guest VM's from malicious host and certain physical attacks. TDX introduces a new operation mode, Secure Arbitration Mode (SEAM) to isolate and protect guest VM's. A TDX guest VM runs in SEAM and, unlike VMX, direct control and interaction with the guest by the host VMM is not possible. Instead, Intel TDX Module, which also runs in SEAM, provides a SEAMCALL API. The SEAMCALL that provides the ability to enter a guest is TDH.VP.ENTER. The TDX Module processes TDH.VP.ENTER, and enters the guest via VMX VMLAUNCH/VMRESUME instructions. When a guest VM-exit requires host VMM interaction, the TDH.VP.ENTER SEAMCALL returns to the host VMM (KVM). Add tdh_vp_enter() to wrap the SEAMCALL invocation of TDH.VP.ENTER. TDH.VP.ENTER is different from other SEAMCALLS in several ways: - it may take some time to return as the guest executes - it uses more arguments - after it returns some host state may need to be restored TDH.VP.ENTER arguments are passed through General Purpose Registers (GPRs). For the special case of the TD guest invoking TDG.VP.VMCALL, nearly any GPR can be used, as well as XMM0 to XMM15. Notably, RBP is not used, and Linux mandates the TDX Module feature NO_RBP_MOD, which is enforced elsewhere. Additionally, XMM registers are not required for the existing Guest Hypervisor Communication Interface and are handled by existing KVM code should they be modified by the guest. There are 2 input formats and 5 output formats for TDH.VP.ENTER arguments. Input #1 : Initial entry or following a previous async. TD Exit Input #2 : Following a previous TDCALL(TDG.VP.VMCALL) Output #1 : On Error (No TD Entry) Output #2 : Async. Exits with a VMX Architectural Exit Reason Output #3 : Async. Exits with a non-VMX TD Exit Status Output #4 : Async. Exits with Cross-TD Exit Details Output #5 : On TDCALL(TDG.VP.VMCALL) Currently, to keep things simple, the wrapper function does not attempt to support different formats, and just passes all the GPRs that could be used. The GPR values are held by KVM in the area set aside for guest GPRs. KVM code uses the guest GPR area (vcpu->arch.regs[]) to set up for or process results of tdh_vp_enter(). Therefore changing tdh_vp_enter() to use more complex argument formats would also alter the way KVM code interacts with tdh_vp_enter(). Signed-off-by: Kai Huang <[email protected]> Signed-off-by: Adrian Hunter <[email protected]>

Intel TDX protects guest VM's from malicious host and certain physical attacks. TDX introduces a new operation mode, Secure Arbitration Mode (SEAM) to isolate and protect guest VM's. A TDX guest VM runs in SEAM and, unlike VMX, direct control and interaction with the guest by the host VMM is not possible. Instead, Intel TDX Module, which also runs in SEAM, provides a SEAMCALL API. The SEAMCALL that provides the ability to enter a guest is TDH.VP.ENTER. The TDX Module processes TDH.VP.ENTER, and enters the guest via VMX VMLAUNCH/VMRESUME instructions. When a guest VM-exit requires host VMM interaction, the TDH.VP.ENTER SEAMCALL returns to the host VMM (KVM). Add tdh_vp_enter() to wrap the SEAMCALL invocation of TDH.VP.ENTER. TDH.VP.ENTER is different from other SEAMCALLS in several ways: - it may take some time to return as the guest executes - it uses more arguments - after it returns some host state may need to be restored TDH.VP.ENTER arguments are passed through General Purpose Registers (GPRs). For the special case of the TD guest invoking TDG.VP.VMCALL, nearly any GPR can be used, as well as XMM0 to XMM15. Notably, RBP is not used, and Linux mandates the TDX Module feature NO_RBP_MOD, which is enforced elsewhere. Additionally, XMM registers are not required for the existing Guest Hypervisor Communication Interface and are handled by existing KVM code should they be modified by the guest. There are 2 input formats and 5 output formats for TDH.VP.ENTER arguments. Input #1 : Initial entry or following a previous async. TD Exit Input #2 : Following a previous TDCALL(TDG.VP.VMCALL) Output #1 : On Error (No TD Entry) Output #2 : Async. Exits with a VMX Architectural Exit Reason Output #3 : Async. Exits with a non-VMX TD Exit Status Output #4 : Async. Exits with Cross-TD Exit Details Output #5 : On TDCALL(TDG.VP.VMCALL) Currently, to keep things simple, the wrapper function does not attempt to support different formats, and just passes all the GPRs that could be used. The GPR values are held by KVM in the area set aside for guest GPRs. KVM code uses the guest GPR area (vcpu->arch.regs[]) to set up for or process results of tdh_vp_enter(). Therefore changing tdh_vp_enter() to use more complex argument formats would also alter the way KVM code interacts with tdh_vp_enter(). Signed-off-by: Kai Huang <[email protected]> --- -Kai: - This is not nice, but for now have no clue on improvement.

Intel TDX protects guest VM's from malicious host and certain physical attacks. TDX introduces a new operation mode, Secure Arbitration Mode (SEAM) to isolate and protect guest VM's. A TDX guest VM runs in SEAM and, unlike VMX, direct control and interaction with the guest by the host VMM is not possible. Instead, Intel TDX Module, which also runs in SEAM, provides a SEAMCALL API. The SEAMCALL that provides the ability to enter a guest is TDH.VP.ENTER. The TDX Module processes TDH.VP.ENTER, and enters the guest via VMX VMLAUNCH/VMRESUME instructions. When a guest VM-exit requires host VMM interaction, the TDH.VP.ENTER SEAMCALL returns to the host VMM (KVM). Add tdh_vp_enter() to wrap the SEAMCALL invocation of TDH.VP.ENTER. TDH.VP.ENTER is different from other SEAMCALLS in several ways: - it may take some time to return as the guest executes - it uses more arguments - after it returns some host state may need to be restored TDH.VP.ENTER arguments are passed through General Purpose Registers (GPRs). For the special case of the TD guest invoking TDG.VP.VMCALL, nearly any GPR can be used, as well as XMM0 to XMM15. Notably, RBP is not used, and Linux mandates the TDX Module feature NO_RBP_MOD, which is enforced elsewhere. Additionally, XMM registers are not required for the existing Guest Hypervisor Communication Interface and are handled by existing KVM code should they be modified by the guest. There are 2 input formats and 5 output formats for TDH.VP.ENTER arguments. Input #1 : Initial entry or following a previous async. TD Exit Input #2 : Following a previous TDCALL(TDG.VP.VMCALL) Output #1 : On Error (No TD Entry) Output #2 : Async. Exits with a VMX Architectural Exit Reason Output #3 : Async. Exits with a non-VMX TD Exit Status Output #4 : Async. Exits with Cross-TD Exit Details Output #5 : On TDCALL(TDG.VP.VMCALL) Currently, to keep things simple, the wrapper function does not attempt to support different formats, and just passes all the GPRs that could be used. The GPR values are held by KVM in the area set aside for guest GPRs. KVM code uses the guest GPR area (vcpu->arch.regs[]) to set up for or process results of tdh_vp_enter(). Therefore changing tdh_vp_enter() to use more complex argument formats would also alter the way KVM code interacts with tdh_vp_enter(). Signed-off-by: Kai Huang <[email protected]> Signed-off-by: Adrian Hunter <[email protected]> Message-ID: <[email protected]> Acked-by: Dave Hansen <[email protected]> Signed-off-by: Paolo Bonzini <[email protected]>

yamahata assigned kiryl and yamahata Jul 18, 2023

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Missing cache information on x86-64 under Intel TDX (glibc bug 30643) #3

Missing cache information on x86-64 under Intel TDX (glibc bug 30643) #3

fweimer-rh commented Jul 18, 2023

fweimer-rh commented Aug 22, 2023

Missing cache information on x86-64 under Intel TDX (glibc bug 30643) #3

Missing cache information on x86-64 under Intel TDX (glibc bug 30643) #3

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fweimer-rh commented Jul 18, 2023

fweimer-rh commented Aug 22, 2023