INFO: task syz-executor594:10971 blocked for more than 143 seconds. Not tainted 5.15.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor594 state:D stack:28152 pid:10971 ppid: 6534 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xb44/0x5960 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6425 __mutex_lock_common kernel/locking/mutex.c:669 [inline] __mutex_lock+0xa34/0x12f0 kernel/locking/mutex.c:729 vhost_net_stop_vq drivers/vhost/net.c:1359 [inline] vhost_net_stop+0x142/0x270 drivers/vhost/net.c:1373 vhost_net_release+0x9c/0x2d0 drivers/vhost/net.c:1405 __fput+0x288/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xbae/0x2a30 kernel/exit.c:825 do_group_exit+0x125/0x310 kernel/exit.c:922 __do_sys_exit_group kernel/exit.c:933 [inline] __se_sys_exit_group kernel/exit.c:931 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fbdad2aeb39 RSP: 002b:00007ffe8b3cf348 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 00007fbdad323330 RCX: 00007fbdad2aeb39 RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffffffffffc0 R09: 00007ffe8b3cf538 R10: 00007ffe8b3cf538 R11: 0000000000000246 R12: 00007fbdad323330 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8b981b20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 1 lock held by in:imklog/6237: #0: ffff8880703ac870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 1 lock held by syz-executor594/10971: #0: ffff88807d6e0218 (&vq->mutex){+.+.}-{3:3}, at: vhost_net_stop_vq drivers/vhost/net.c:1359 [inline] #0: ffff88807d6e0218 (&vq->mutex){+.+.}-{3:3}, at: vhost_net_stop+0x142/0x270 drivers/vhost/net.c:1373 1 lock held by vhost-10971/10972: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 26 Comm: khungtaskd Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 21222 Comm: kworker/u4:0 Not tainted 5.15.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:438 [inline] RIP: 0010:lock_is_held_type+0xe2/0x140 kernel/locking/lockdep.c:5669 Code: 0f b6 47 22 45 31 ed 83 e0 03 44 39 f0 41 0f 94 c5 48 c7 c7 60 ff 8b 89 e8 bb 0d 00 00 b8 ff ff ff ff 65 0f c1 05 4e a9 cb 76 <83> f8 01 75 29 9c 58 f6 c4 02 75 3d 48 f7 04 24 00 02 00 00 74 01 RSP: 0018:ffffc90003bff758 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 0000000000000003 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000000 RBP: ffffffff8b981a60 R08: 0000000000000000 R09: ffff8880b9c32a0b R10: ffffed1017386541 R11: 000000000004b7d2 R12: ffff888078989c80 R13: 0000000000000000 R14: 00000000ffffffff R15: ffff88807898a6f0 FS: 0000000000000000(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbdad3241d0 CR3: 000000000b68e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x3a/0x70 kernel/rcu/update.c:125 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5596 rcu_lock_acquire include/linux/rcupdate.h:267 [inline] rcu_read_lock include/linux/rcupdate.h:687 [inline] cpuacct_charge+0x87/0x330 kernel/sched/cpuacct.c:348 cgroup_account_cputime include/linux/cgroup.h:792 [inline] update_curr+0x353/0x8c0 kernel/sched/fair.c:853 dequeue_entity+0x23/0xef0 kernel/sched/fair.c:4392 dequeue_task_fair+0x234/0xea0 kernel/sched/fair.c:5720 deactivate_task kernel/sched/core.c:2010 [inline] __schedule+0xc9f/0x5960 kernel/sched/core.c:6241 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 toggle_allocation_gate mm/kfence/core.c:633 [inline] toggle_allocation_gate+0x309/0x390 mm/kfence/core.c:618 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.200 msecs ---------------- Code disassembly (best guess): 0: 0f b6 47 22 movzbl 0x22(%rdi),%eax 4: 45 31 ed xor %r13d,%r13d 7: 83 e0 03 and $0x3,%eax a: 44 39 f0 cmp %r14d,%eax d: 41 0f 94 c5 sete %r13b 11: 48 c7 c7 60 ff 8b 89 mov $0xffffffff898bff60,%rdi 18: e8 bb 0d 00 00 callq 0xdd8 1d: b8 ff ff ff ff mov $0xffffffff,%eax 22: 65 0f c1 05 4e a9 cb xadd %eax,%gs:0x76cba94e(%rip) # 0x76cba978 29: 76 * 2a: 83 f8 01 cmp $0x1,%eax <-- trapping instruction 2d: 75 29 jne 0x58 2f: 9c pushfq 30: 58 pop %rax 31: f6 c4 02 test $0x2,%ah 34: 75 3d jne 0x73 36: 48 f7 04 24 00 02 00 testq $0x200,(%rsp) 3d: 00 3e: 74 01 je 0x41