INFO: task kworker/u4:4:1180 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:24880 pid: 1180 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 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 io_uring_try_cancel_iowq fs/io_uring.c:9570 [inline] io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9600 io_ring_exit_work+0x137/0x19a0 fs/io_uring.c:9400 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: task kworker/u4:2:24099 blocked for more than 143 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:2 state:D stack:24640 pid:24099 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 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 io_ring_exit_work+0x4bb/0x19a0 fs/io_uring.c:9442 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: task kworker/u4:9:1294 blocked for more than 144 seconds. Not tainted 5.15.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:9 state:D stack:25488 pid: 1294 ppid: 2 flags:0x00004000 Workqueue: events_unbound io_ring_exit_work Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0x940/0x26f0 kernel/sched/core.c:6287 schedule+0xd3/0x270 kernel/sched/core.c:6366 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 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 io_ring_exit_work+0x4bb/0x19a0 fs/io_uring.c:9442 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 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8b97fde0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 3 locks held by kworker/u4:4/1180: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc900052bfdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffff888099bd60a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9570 [inline] #2: ffff888099bd60a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9600 1 lock held by in:imklog/6235: #0: ffff88802497e870 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:990 2 locks held by agetty/6465: #0: ffff88801d3be098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc900011b82e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 1 lock held by vivid-001-sdr-c/14913: 2 locks held by kworker/u4:2/24099: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc9001846fdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 2 locks held by kworker/u4:9/1294: #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1198 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:634 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:661 [inline] #0: ffff888010c69138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x8a3/0x16b0 kernel/workqueue.c:2268 #1: ffffc90018aa7db0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 2 locks held by syz-executor.3/20027: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.15.0-rc3-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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8534 Comm: kworker/1:3 Not tainted 5.15.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events nsim_dev_trap_report_work RIP: 0010:kasan_check_range+0x12b/0x180 mm/kasan/generic.c:190 Code: 3a 00 74 ef 49 8d 04 2c 48 85 d2 75 0b 48 89 da 48 29 c2 e9 55 ff ff ff 49 39 d2 75 17 49 0f be 02 41 83 e1 07 49 39 c1 7d 0a <5b> b8 01 00 00 00 5d 41 5c c3 44 89 c2 e8 73 f0 ff ff 5b 83 f0 01 RSP: 0018:ffffc9000c937840 EFLAGS: 00000046 RAX: fffffbfff1f9f941 RBX: fffffbfff1f9f941 RCX: ffffffff815af5fd RDX: fffffbfff1f9f941 RSI: 0000000000000008 RDI: ffffffff8fcfca00 RBP: fffffbfff1f9f940 R08: 0000000000000000 R09: ffffffff8fcfca07 R10: fffffbfff1f9f940 R11: 0000000000086089 R12: 0000000000000003 R13: ffff88803f66b900 R14: ffff88803f66c2f8 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f717c705000 CR3: 00000000249e4000 CR4: 00000000003526e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] hlock_class kernel/locking/lockdep.c:199 [inline] check_wait_context kernel/locking/lockdep.c:4713 [inline] __lock_acquire+0x6ed/0x54a0 kernel/locking/lockdep.c:4965 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 local_lock_acquire include/linux/local_lock_internal.h:29 [inline] ___slab_alloc+0x157/0xfe0 mm/slub.c:2918 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3081 slab_alloc_node mm/slub.c:3172 [inline] __kmalloc_node_track_caller+0x2d2/0x340 mm/slub.c:4936 kmalloc_reserve net/core/skbuff.c:355 [inline] __alloc_skb+0xde/0x340 net/core/skbuff.c:426 alloc_skb include/linux/skbuff.h:1116 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline] nsim_dev_trap_report_work+0x2ac/0xbd0 drivers/net/netdevsim/dev.c:762 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 ---------------- Code disassembly (best guess): 0: 3a 00 cmp (%rax),%al 2: 74 ef je 0xfffffff3 4: 49 8d 04 2c lea (%r12,%rbp,1),%rax 8: 48 85 d2 test %rdx,%rdx b: 75 0b jne 0x18 d: 48 89 da mov %rbx,%rdx 10: 48 29 c2 sub %rax,%rdx 13: e9 55 ff ff ff jmpq 0xffffff6d 18: 49 39 d2 cmp %rdx,%r10 1b: 75 17 jne 0x34 1d: 49 0f be 02 movsbq (%r10),%rax 21: 41 83 e1 07 and $0x7,%r9d 25: 49 39 c1 cmp %rax,%r9 28: 7d 0a jge 0x34 * 2a: 5b pop %rbx <-- trapping instruction 2b: b8 01 00 00 00 mov $0x1,%eax 30: 5d pop %rbp 31: 41 5c pop %r12 33: c3 retq 34: 44 89 c2 mov %r8d,%edx 37: e8 73 f0 ff ff callq 0xfffff0af 3c: 5b pop %rbx 3d: 83 f0 01 xor $0x1,%eax