INFO: task syz-executor101:8474 blocked for more than 143 seconds. Not tainted 5.14.0-rc2-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor101 state:D stack:27408 pid: 8474 ppid: 8473 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4683 [inline] __schedule+0x93a/0x26f0 kernel/sched/core.c:5940 schedule+0xd3/0x270 kernel/sched/core.c:6019 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1854 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x176/0x280 kernel/sched/completion.c:138 flush_workqueue+0x3ff/0x1600 kernel/workqueue.c:2839 nbd_start_device_ioctl drivers/block/nbd.c:1350 [inline] __nbd_ioctl drivers/block/nbd.c:1411 [inline] nbd_ioctl+0x60e/0xa50 drivers/block/nbd.c:1451 blkdev_ioctl+0x2a1/0x6d0 block/ioctl.c:585 block_ioctl+0xf9/0x140 fs/block_dev.c:1602 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 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: 0033:0x444279 RSP: 002b:00007ffc8db35ca8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004004a0 RCX: 0000000000444279 RDX: 00000000ffffffff RSI: 000000000000ab03 RDI: 0000000000000005 RBP: 0000000000000000 R08: 00007ffc8db35e48 R09: 00007ffc8db35e48 R10: 00007ffc8db35e48 R11: 0000000000000246 R12: 0000000000403590 R13: 431bde82d7b634db R14: 00000000004b2018 R15: 00000000004004a0 Showing all locks held in the system: 2 locks held by kworker/u4:3/83: 1 lock held by khungtaskd/1649: #0: ffffffff8b97b9c0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 2 locks held by kworker/u5:0/2035: #0: ffff888019337938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888019337938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:620 [inline] #0: ffff888019337938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline] #0: ffff888019337938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:617 [inline] #0: ffff888019337938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:644 [inline] #0: ffff888019337938 ((wq_completion)knbd0-recv){+.+.}-{0:0}, at: process_one_work+0x871/0x1630 kernel/workqueue.c:2247 #1: ffffc900077dfdb0 ((work_completion)(&args->work)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x1630 kernel/workqueue.c:2251 1 lock held by in:imklog/8376: #0: ffff888023782870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:974 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1649 Comm: khungtaskd Not tainted 5.14.0-rc2-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:105 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x1b3/0x230 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+0xd0a/0xfc0 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 83 Comm: kworker/u4:3 Not tainted 5.14.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:task_irq_context kernel/locking/lockdep.c:4523 [inline] RIP: 0010:__lock_acquire+0x315/0x54a0 kernel/locking/lockdep.c:4953 Code: 00 00 00 fc ff df 48 89 f1 48 89 74 24 40 49 89 44 24 18 65 8b 05 63 50 a7 7e 85 c0 0f 95 c0 48 c1 e9 03 83 e6 07 0f b6 0c 11 <48> 89 f2 0f b6 c0 83 c2 03 01 c0 38 ca 7c 08 84 c9 0f 85 70 12 00 RSP: 0018:ffffc9000104f790 EFLAGS: 00000002 RAX: 0000000000000000 RBX: ffff8880109ae138 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff888014b88ac8 RBP: 0000000000000000 R08: 1ffff11002971156 R09: 0000000000000000 R10: 0000000000000000 R11: 000000000000003f R12: ffff888014b88ab8 R13: ffff888014b88000 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fec49b53000 CR3: 000000000b68e000 CR4: 0000000000350ee0 Call Trace: lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:151 spin_lock include/linux/spinlock.h:354 [inline] __get_locked_pte+0x2b6/0x4d0 mm/memory.c:1736 get_locked_pte include/linux/mm.h:2051 [inline] __text_poke+0x1ab/0x8c0 arch/x86/kernel/alternative.c:817 text_poke_bp_batch+0x3d7/0x560 arch/x86/kernel/alternative.c:1178 text_poke_flush arch/x86/kernel/alternative.c:1268 [inline] text_poke_flush arch/x86/kernel/alternative.c:1265 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1275 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:145 jump_label_update+0x1d5/0x430 kernel/jump_label.c:830 static_key_enable_cpuslocked+0x1b1/0x260 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 toggle_allocation_gate mm/kfence/core.c:623 [inline] toggle_allocation_gate+0x100/0x390 mm/kfence/core.c:615 process_one_work+0x98d/0x1630 kernel/workqueue.c:2276 worker_thread+0x658/0x11f0 kernel/workqueue.c:2422 kthread+0x3e5/0x4d0 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295