INFO: task kworker/u4:4:1122 blocked for more than 143 seconds. Not tainted 5.15.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:4 state:D stack:24864 pid: 1122 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 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8b97fe20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6446 3 locks held by kworker/u4:4/1122: #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: ffffc9000520fdb0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work+0x8d7/0x16b0 kernel/workqueue.c:2272 #2: ffff8880882e80a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_iowq fs/io_uring.c:9570 [inline] #2: ffff8880882e80a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_try_cancel_requests+0x7d1/0xc30 fs/io_uring.c:9600 1 lock held by in:imklog/6224: 1 lock held by syz-executor.2/28985: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-rc4-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: 28985 Comm: syz-executor.2 Not tainted 5.15.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:unwind_next_frame+0xb6/0x1ce0 arch/x86/kernel/unwind_orc.c:621 Code: 00 fc ff df 48 c7 04 13 00 00 00 00 48 8b 8c 24 98 00 00 00 65 48 2b 0c 25 28 00 00 00 0f 85 4c 15 00 00 48 81 c4 a0 00 00 00 <5b> 5d 41 5c 41 5d 41 5e 41 5f c3 4d 8d 66 48 48 b8 00 00 00 00 00 RSP: 0018:ffffc9000ab9f7b0 EFLAGS: 00000282 RAX: 0000000000000001 RBX: 1ffff92001573eea RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffc9000ab9f910 R08: ffffffff8decb14a R09: 0000000000000001 R10: fffff52001573f08 R11: 0000000000086089 R12: ffffc9000ab98000 R13: ffffc9000ab9f81d R14: ffffc9000ab9f7e8 R15: ffffffff8decb14e FS: 00007f967b38c700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f34ccbd9000 CR3: 000000008a9d2000 CR4: 0000000000350ef0 Call Trace: arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:121 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] ____kasan_kmalloc mm/kasan/common.c:472 [inline] __kasan_kmalloc+0xa4/0xd0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:591 [inline] io_add_buffers fs/io_uring.c:4385 [inline] io_provide_buffers fs/io_uring.c:4419 [inline] io_issue_sqe+0x3289/0x7180 fs/io_uring.c:6731 __io_queue_sqe+0x90/0xb50 fs/io_uring.c:6960 io_req_task_submit+0xbf/0x1b0 fs/io_uring.c:2234 tctx_task_work+0x189/0x6c0 fs/io_uring.c:2159 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_signal include/linux/tracehook.h:214 [inline] handle_signal_work kernel/entry/common.c:146 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x256/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f967de158d9 Code: Unable to access opcode bytes at RIP 0x7f967de158af. RSP: 002b:00007f967b38c188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 00000000000002ff RBX: 00007f967df19f60 RCX: 00007f967de158d9 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007f967de6fcb4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff63238adf R14: 00007f967b38c300 R15: 0000000000022000 ---------------- Code disassembly (best guess), 3 bytes skipped: 0: df 48 c7 fisttps -0x39(%rax) 3: 04 13 add $0x13,%al 5: 00 00 add %al,(%rax) 7: 00 00 add %al,(%rax) 9: 48 8b 8c 24 98 00 00 mov 0x98(%rsp),%rcx 10: 00 11: 65 48 2b 0c 25 28 00 sub %gs:0x28,%rcx 18: 00 00 1a: 0f 85 4c 15 00 00 jne 0x156c 20: 48 81 c4 a0 00 00 00 add $0xa0,%rsp * 27: 5b pop %rbx <-- trapping instruction 28: 5d pop %rbp 29: 41 5c pop %r12 2b: 41 5d pop %r13 2d: 41 5e pop %r14 2f: 41 5f pop %r15 31: c3 retq 32: 4d 8d 66 48 lea 0x48(%r14),%r12 36: 48 rex.W 37: b8 00 00 00 00 mov $0x0,%eax