INFO: task syz-executor.5:710 blocked for more than 143 seconds. Not tainted 5.16.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:26408 pid: 710 ppid: 13210 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 io_uring_cancel_generic+0x53d/0x690 fs/io_uring.c:9877 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x60c/0x2b40 kernel/exit.c:787 do_group_exit+0x125/0x310 kernel/exit.c:929 get_signal+0x47d/0x2220 kernel/signal.c:2852 arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868 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+0x17d/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: 0033:0x7fd2f3a63ae7 RSP: 002b:00007fd2f29d9218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 00000000000000ca RBX: 00007fd2f3b76f68 RCX: 00007fd2f3a63ae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fd2f3b76f68 RBP: 00007fd2f3b76f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fd2f3b76f6c R13: 00007fff636a064f R14: 00007fd2f29d9300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83b60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 2 locks held by kworker/u4:4/1012: #0: ffff8880b9d39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 #1: ffff8880b9d279c8 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x173/0x490 kernel/sched/psi.c:871 2 locks held by in:imklog/6216: #0: ffff88807df16370 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:994 #1: ffff8880b9d39a98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:478 2 locks held by agetty/30275: #0: ffff88801e8b7098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:252 #1: ffffc90004c2b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcf0/0x1230 drivers/tty/n_tty.c:2113 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.16.0-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:111 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+0xc1d/0xf50 kernel/hung_task.c:295 kthread+0x405/0x4f0 kernel/kthread.c:327 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: 6518 Comm: syz-fuzzer Not tainted 5.16.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:debug_spin_lock_after kernel/locking/spinlock_debug.c:94 [inline] RIP: 0010:do_raw_spin_lock+0x171/0x2b0 kernel/locking/spinlock_debug.c:117 Code: fc ff df 4c 89 e2 48 c1 ea 03 0f b6 14 02 4c 89 e0 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 d9 00 00 00 4c 89 ea 44 89 75 08 <48> b8 00 00 00 00 00 fc ff df 48 c1 ea 03 65 4c 8b 24 25 40 70 02 RSP: 0018:ffffc9000bc178f8 EFLAGS: 00000046 RAX: 0000000000000003 RBX: 1ffff92001782f20 RCX: ffffffff815d3180 RDX: ffffffff90758810 RSI: 0000000000000004 RDI: ffffc9000bc17920 RBP: ffffffff90758800 R08: 0000000000000001 R09: 0000000000000003 R10: fffff52001782f24 R11: 0000000000000000 R12: ffffffff90758808 R13: ffffffff90758810 R14: 0000000000000000 R15: ffffffff89ae0400 FS: 000000c00002e490(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff8f8d14020 CR3: 000000006f1d6000 CR4: 0000000000350ef0 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline] _raw_spin_lock_irqsave+0x41/0x50 kernel/locking/spinlock.c:162 debug_object_activate+0x12e/0x3e0 lib/debugobjects.c:661 debug_hrtimer_activate kernel/time/hrtimer.c:420 [inline] debug_activate kernel/time/hrtimer.c:475 [inline] enqueue_hrtimer+0x27/0x3e0 kernel/time/hrtimer.c:1084 __hrtimer_start_range_ns kernel/time/hrtimer.c:1258 [inline] hrtimer_start_range_ns+0x78a/0xa80 kernel/time/hrtimer.c:1298 hrtimer_start_expires include/linux/hrtimer.h:432 [inline] hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1965 [inline] schedule_hrtimeout_range_clock+0x183/0x390 kernel/time/hrtimer.c:2302 ep_poll fs/eventpoll.c:1849 [inline] do_epoll_wait+0x1298/0x1940 fs/eventpoll.c:2227 do_compat_epoll_pwait.part.0+0x29/0x1d0 fs/eventpoll.c:2261 do_epoll_pwait fs/eventpoll.c:2268 [inline] __do_sys_epoll_pwait fs/eventpoll.c:2274 [inline] __se_sys_epoll_pwait fs/eventpoll.c:2268 [inline] __x64_sys_epoll_pwait+0x1cf/0x310 fs/eventpoll.c:2268 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: 0033:0x46e420 Code: 0f 05 89 44 24 20 c3 cc cc cc 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 44 8b 54 24 1c 49 c7 c0 00 00 00 00 b8 19 01 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc RSP: 002b:000000c00003f7f0 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 000000000046e420 RDX: 0000000000000080 RSI: 000000c00003f840 RDI: 0000000000000003 RBP: 000000c00003fe40 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000003 R13: 000000c000000900 R14: 000080c023800000 R15: 000000000000aa55 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: df 4c 89 e2 fisttps -0x1e(%rcx,%rcx,4) 4: 48 c1 ea 03 shr $0x3,%rdx 8: 0f b6 14 02 movzbl (%rdx,%rax,1),%edx c: 4c 89 e0 mov %r12,%rax f: 83 e0 07 and $0x7,%eax 12: 83 c0 03 add $0x3,%eax 15: 38 d0 cmp %dl,%al 17: 7c 08 jl 0x21 19: 84 d2 test %dl,%dl 1b: 0f 85 d9 00 00 00 jne 0xfa 21: 4c 89 ea mov %r13,%rdx 24: 44 89 75 08 mov %r14d,0x8(%rbp) * 28: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction 2f: fc ff df 32: 48 c1 ea 03 shr $0x3,%rdx 36: 65 gs 37: 4c rex.WR 38: 8b .byte 0x8b 39: 24 25 and $0x25,%al 3b: 40 70 02 rex jo 0x40