INFO: task syz-executor.5:10626 blocked for more than 143 seconds. Not tainted 5.15.0-next-20211104-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.5 state:D stack:27824 pid:10626 ppid: 6746 flags:0x00024004 Call Trace: context_switch kernel/sched/core.c:4984 [inline] __schedule+0xa9a/0x4940 kernel/sched/core.c:6265 schedule+0xd2/0x260 kernel/sched/core.c:6338 io_uring_cancel_generic+0x53d/0x690 fs/io_uring.c:9850 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:2830 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: 0033:0x7f3b67711ae7 RSP: 002b:00007f3b64c66218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 00000000000000ca RBX: 00007f3b67825028 RCX: 00007f3b67711ae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f3b67825028 RBP: 00007f3b67825020 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f3b6782502c R13: 00007ffcd65bff0f R14: 00007f3b64c66300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8bb83a60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6458 2 locks held by systemd-journal/2970: 1 lock held by in:imklog/6223: ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.0-next-20211104-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:254 [inline] watchdog+0xcb7/0xed0 kernel/hung_task.c:339 kthread+0x405/0x4f0 kernel/kthread.c:327 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: 56 Comm: kworker/u4:3 Not tainted 5.15.0-next-20211104-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:insn_get_opcode.part.0+0x5c8/0x990 arch/x86/lib/insn.c:303 Code: 89 e1 48 c1 ea 03 83 e1 07 0f b6 14 2a 38 ca 7f 08 84 d2 0f 85 f9 02 00 00 48 8b 4c 24 08 45 0f b6 34 24 4c 89 7b 68 48 89 c8 <83> e1 07 48 c1 e8 03 0f b6 04 28 38 c8 7f 08 84 c0 0f 85 de 02 00 RSP: 0018:ffffc90001a2f918 EFLAGS: 00000246 RAX: ffffc90001a2fa9d RBX: ffffc90001a2fa80 RCX: ffffc90001a2fa9d RDX: 0000000000000000 RSI: ffffffff840bfa3a RDI: 0000000000000003 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff840bf915 R11: 0000000000000000 R12: ffffffff89a61a0b R13: ffffc90001a2facc R14: 000000000000001f R15: ffffffff89a61a0c FS: 0000000000000000(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5f3b68c000 CR3: 000000000b88e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: insn_get_opcode arch/x86/lib/insn.c:271 [inline] insn_get_modrm+0x355/0x7c0 arch/x86/lib/insn.c:343 insn_get_sib+0x29c/0x330 arch/x86/lib/insn.c:421 insn_get_displacement+0x346/0x6c0 arch/x86/lib/insn.c:464 insn_get_immediate arch/x86/lib/insn.c:632 [inline] insn_get_length arch/x86/lib/insn.c:707 [inline] insn_decode+0x473/0x4e0 arch/x86/lib/insn.c:747 text_poke_loc_init+0xa3/0x340 arch/x86/kernel/alternative.c:1387 arch_jump_label_transform_queue+0x94/0x100 arch/x86/kernel/jump_label.c:138 __jump_label_update+0x12e/0x400 kernel/jump_label.c:451 jump_label_update+0x1d5/0x430 kernel/jump_label.c:830 static_key_disable_cpuslocked+0x152/0x1b0 kernel/jump_label.c:207 static_key_disable+0x16/0x20 kernel/jump_label.c:215 toggle_allocation_gate mm/kfence/core.c:746 [inline] toggle_allocation_gate+0x183/0x390 mm/kfence/core.c:724 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 89 e1 mov %esp,%ecx 2: 48 c1 ea 03 shr $0x3,%rdx 6: 83 e1 07 and $0x7,%ecx 9: 0f b6 14 2a movzbl (%rdx,%rbp,1),%edx d: 38 ca cmp %cl,%dl f: 7f 08 jg 0x19 11: 84 d2 test %dl,%dl 13: 0f 85 f9 02 00 00 jne 0x312 19: 48 8b 4c 24 08 mov 0x8(%rsp),%rcx 1e: 45 0f b6 34 24 movzbl (%r12),%r14d 23: 4c 89 7b 68 mov %r15,0x68(%rbx) 27: 48 89 c8 mov %rcx,%rax * 2a: 83 e1 07 and $0x7,%ecx <-- trapping instruction 2d: 48 c1 e8 03 shr $0x3,%rax 31: 0f b6 04 28 movzbl (%rax,%rbp,1),%eax 35: 38 c8 cmp %cl,%al 37: 7f 08 jg 0x41 39: 84 c0 test %al,%al 3b: 0f .byte 0xf 3c: 85 de test %ebx,%esi 3e: 02 00 add (%rax),%al