INFO: task syz-executor.4:16375 blocked for more than 143 seconds. Not tainted 5.14.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:21360 pid:16375 ppid: 6655 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:4940 [inline] __schedule+0xc8d/0x1270 kernel/sched/core.c:6287 schedule+0x14b/0x210 kernel/sched/core.c:6366 schedule_timeout+0xac/0x300 kernel/time/timer.c:1857 do_wait_for_common+0x2da/0x480 kernel/sched/completion.c:85 __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x48/0x60 kernel/sched/completion.c:138 io_wq_exit_workers fs/io-wq.c:1162 [inline] io_wq_put_and_exit+0x75f/0xde0 fs/io-wq.c:1197 io_uring_clean_tctx fs/io_uring.c:9609 [inline] io_uring_cancel_generic+0x9d3/0xba0 fs/io_uring.c:9689 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x280/0x2580 kernel/exit.c:780 do_group_exit+0x168/0x2d0 kernel/exit.c:922 get_signal+0x16e0/0x20c0 kernel/signal.c:2868 arch_do_signal_or_restart+0x9c/0x730 arch/x86/kernel/signal.c:865 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x191/0x220 kernel/entry/common.c:209 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:302 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665f9 RSP: 002b:00007fef063a9188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 0000000000000304 RBX: 000000000056bf80 RCX: 00000000004665f9 RDX: 0000000000000000 RSI: 0000000000000304 RDI: 0000000000000004 RBP: 00000000004bfcc4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007fff6ddd8a2f R14: 00007fef063a9300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/26: #0: ffffffff8c91c140 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 2 locks held by kworker/u4:2/148: #0: ffff8880b9c31558 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x1b/0x30 kernel/sched/core.c:474 #1: ffff8880b9d1f888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x4c1/0x780 kernel/sched/psi.c:880 1 lock held by in:imklog/6208: #0: ffff88807d346d70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:990 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 26 Comm: khungtaskd Not tainted 5.14.0-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+0x1dc/0x2d8 lib/dump_stack.c:106 nmi_cpu_backtrace+0x45f/0x490 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x16a/0x280 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+0xc54/0xca0 kernel/hung_task.c:295 kthread+0x453/0x480 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 2965 Comm: systemd-journal Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:193 Code: 84 00 00 00 00 00 0f 1f 40 00 be 0d 00 00 00 48 c7 c7 a0 8c 95 8c e8 6f 4e 4b 00 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc <48> 8b 04 24 65 48 8b 0c 25 c0 ef 01 00 65 8b 15 24 7a 7f 7e f7 c2 RSP: 0018:ffffc900022bfb78 EFLAGS: 00000202 RAX: 1ffff1100f75aa01 RBX: 1ffff1100f75aa27 RCX: 0000000000000000 RDX: ffff88807bad5130 RSI: ffff88807bad5130 RDI: ffff888019ad5198 RBP: ffffc900022bfdd0 R08: ffffffff81ee0bda R09: ffffed100f49a001 R10: ffffed100f49a001 R11: 0000000000000000 R12: 0000000000000001 R13: dffffc0000000000 R14: ffff888019ad5198 R15: ffff88807bad5130 FS: 00007f388fda48c0(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f388d202000 CR3: 000000001a24b000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_add include/linux/list.h:70 [inline] list_add_tail include/linux/list.h:100 [inline] ep_send_events fs/eventpoll.c:1712 [inline] ep_poll+0xcc4/0x1e80 fs/eventpoll.c:1799 do_epoll_wait+0x1b2/0x230 fs/eventpoll.c:2227 __do_sys_epoll_wait fs/eventpoll.c:2239 [inline] __se_sys_epoll_wait fs/eventpoll.c:2234 [inline] __x64_sys_epoll_wait+0x307/0x350 fs/eventpoll.c:2234 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f388f06d2e3 Code: 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 83 3d 29 54 2b 00 00 75 13 49 89 ca b8 e8 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 34 c3 48 83 ec 08 e8 0b c2 00 00 48 89 04 24 RSP: 002b:00007ffec583c528 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 000055662236a1e0 RCX: 00007f388f06d2e3 RDX: 0000000000000013 RSI: 00007ffec583c530 RDI: 0000000000000008 RBP: 00007ffec583c720 R08: 00007ffec59f4080 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffec583c530 R13: 0000000000000001 R14: 0000000000000000 R15: 0005cbb626279b7b ---------------- Code disassembly (best guess): 0: 84 00 test %al,(%rax) 2: 00 00 add %al,(%rax) 4: 00 00 add %al,(%rax) 6: 0f 1f 40 00 nopl 0x0(%rax) a: be 0d 00 00 00 mov $0xd,%esi f: 48 c7 c7 a0 8c 95 8c mov $0xffffffff8c958ca0,%rdi 16: e8 6f 4e 4b 00 callq 0x4b4e8a 1b: c3 retq 1c: cc int3 1d: cc int3 1e: cc int3 1f: cc int3 20: cc int3 21: cc int3 22: cc int3 23: cc int3 24: cc int3 25: cc int3 26: cc int3 27: cc int3 28: cc int3 29: cc int3 * 2a: 48 8b 04 24 mov (%rsp),%rax <-- trapping instruction 2e: 65 48 8b 0c 25 c0 ef mov %gs:0x1efc0,%rcx 35: 01 00 37: 65 8b 15 24 7a 7f 7e mov %gs:0x7e7f7a24(%rip),%edx # 0x7e7f7a62 3e: f7 .byte 0xf7 3f: c2 .byte 0xc2