INFO: task syz-executor.4:9684 blocked for more than 143 seconds. Not tainted 5.18.0-rc7-syzkaller-00048-gf993aed406ea #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:27240 pid: 9684 ppid: 3625 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5073 [inline] __schedule+0xa9a/0x4cc0 kernel/sched/core.c:6388 schedule+0xd2/0x1f0 kernel/sched/core.c:6460 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1860 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common+0x373/0x530 kernel/sched/completion.c:106 io_wq_exit_workers fs/io-wq.c:1266 [inline] io_wq_put_and_exit+0x4d6/0xe40 fs/io-wq.c:1301 io_uring_clean_tctx fs/io_uring.c:10394 [inline] io_uring_cancel_generic+0x538/0x5bc fs/io_uring.c:10464 io_uring_files_cancel include/linux/io_uring.h:18 [inline] do_exit+0x4f9/0x2a00 kernel/exit.c:750 do_group_exit+0xd2/0x2f0 kernel/exit.c:925 get_signal+0x22df/0x24c0 kernel/signal.c:2864 arch_do_signal_or_restart+0x82/0x20f0 arch/x86/kernel/signal.c:867 exit_to_user_mode_loop kernel/entry/common.c:166 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:294 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd8d1e890e9 RSP: 002b:00007fd8d3016168 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: 000000000000242a RBX: 00007fd8d1f9bf60 RCX: 00007fd8d1e890e9 RDX: 0000000000000000 RSI: 000000000000242a RDI: 0000000000000006 RBP: 00007fd8d30161d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffd7861383f R14: 00007fd8d3016300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/28: #0: ffffffff8bd820e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6467 1 lock held by udevd/2964: 2 locks held by getty/3275: #0: ffff88814b7b0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:244 #1: ffffc90002ce62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xcea/0x1230 drivers/tty/n_tty.c:2075 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted 5.18.0-rc7-syzkaller-00048-gf993aed406ea #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+0x1e6/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xc1d/0xf50 kernel/hung_task.c:369 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 2964 Comm: udevd Not tainted 5.18.0-rc7-syzkaller-00048-gf993aed406ea #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x2a2/0x56c0 kernel/locking/lockdep.c:4965 Code: 00 00 00 00 fc ff df 80 3c 02 00 0f 85 68 3c 00 00 48 8b 84 24 48 01 00 00 49 8d 7c 24 10 48 89 fa 48 c1 ea 03 49 89 44 24 08 <48> b8 00 00 00 00 00 fc ff df 80 3c 02 00 0f 85 60 3a 00 00 49 8d RSP: 0018:ffffc90002ccf920 EFLAGS: 00000012 RAX: ffffffff81d8106c RBX: ffffffff8bda1e08 RCX: 0000000000000043 RDX: 1ffff1100fada8ae RSI: 0000000000000000 RDI: ffff88807d6d4570 RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000001 R12: ffff88807d6d4560 R13: ffff88807d6d3b00 R14: 0000000000000002 R15: 0000000000000001 FS: 00007f06f9dc4840(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005607b8d5c600 CR3: 000000001b9bc000 CR4: 0000000000350ef0 Call Trace: lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 seqcount_lockdep_reader_access include/linux/seqlock.h:103 [inline] ktime_get_ts64+0x487/0x560 kernel/time/timekeeping.c:960 select_estimate_accuracy+0xcc/0x320 fs/select.c:88 ep_poll fs/eventpoll.c:1778 [inline] do_epoll_wait+0x14e9/0x1930 fs/eventpoll.c:2234 __do_sys_epoll_wait fs/eventpoll.c:2246 [inline] __se_sys_epoll_wait fs/eventpoll.c:2241 [inline] __x64_sys_epoll_wait+0x158/0x270 fs/eventpoll.c:2241 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: 0033:0x7f06f9933e46 Code: 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 e8 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 5a c3 90 48 83 ec 28 89 54 24 18 48 89 74 24 RSP: 002b:00007ffe8ea6ddd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e8 RAX: ffffffffffffffda RBX: 00007ffe8ea6ded8 RCX: 00007f06f9933e46 RDX: 0000000000000008 RSI: 00007ffe8ea6ded8 RDI: 000000000000000b RBP: 000056144c515e40 R08: 0000000020de12f8 R09: 00007ffe8eac9080 R10: 0000000000000bb8 R11: 0000000000000246 R12: 0000000000000bb8 R13: 000056144c510190 R14: 0000000000000000 R15: 0000000000000000 ---------------- Code disassembly (best guess), 6 bytes skipped: 0: df 80 3c 02 00 0f filds 0xf00023c(%rax) 6: 85 68 3c test %ebp,0x3c(%rax) 9: 00 00 add %al,(%rax) b: 48 8b 84 24 48 01 00 mov 0x148(%rsp),%rax 12: 00 13: 49 8d 7c 24 10 lea 0x10(%r12),%rdi 18: 48 89 fa mov %rdi,%rdx 1b: 48 c1 ea 03 shr $0x3,%rdx 1f: 49 89 44 24 08 mov %rax,0x8(%r12) * 24: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax <-- trapping instruction 2b: fc ff df 2e: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 32: 0f 85 60 3a 00 00 jne 0x3a98 38: 49 rex.WB 39: 8d .byte 0x8d