INFO: task syz-executor.4:21644 blocked for more than 143 seconds. Not tainted 5.15.0-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.4 state:D stack:25488 pid:21644 ppid: 6812 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4969 [inline] __schedule+0xb72/0x1460 kernel/sched/core.c:6250 schedule+0x12b/0x1f0 kernel/sched/core.c:6323 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6382 __mutex_lock_common+0xd1f/0x2590 kernel/locking/mutex.c:680 __mutex_lock kernel/locking/mutex.c:740 [inline] mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:792 io_uring_del_tctx_node+0xe4/0x2a9 fs/io_uring.c:9746 io_uring_clean_tctx+0x192/0x1d5 fs/io_uring.c:9762 io_uring_cancel_generic+0x624/0x661 fs/io_uring.c:9851 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x281/0x24f0 kernel/exit.c:787 do_group_exit+0x168/0x2d0 kernel/exit.c:929 get_signal+0x1740/0x2120 kernel/signal.c:2830 arch_do_signal_or_restart+0x9c/0x730 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+0x191/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f7c0b5d0ae9 RSP: 002b:00007f7c08b46188 EFLAGS: 00000246 ORIG_RAX: 00000000000000e9 RAX: 0000000000000000 RBX: 00007f7c0b6e3f60 RCX: 00007f7c0b5d0ae9 RDX: 0000000000000007 RSI: 0000000000000001 RDI: 0000000000000005 RBP: 00007f7c0b62af6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020000040 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcc8620aef R14: 00007f7c08b46300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/27: #0: ffffffff8cb1d940 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 1 lock held by in:imklog/6207: 2 locks held by agetty/30962: #0: ffff88806325b098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002dbb2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6c5/0x1c60 drivers/tty/n_tty.c:2113 1 lock held by syz-executor.4/21644: #0: ffff8880767380a8 (&ctx->uring_lock){+.+.}-{3:3}, at: io_uring_del_tctx_node+0xe4/0x2a9 fs/io_uring.c:9746 4 locks held by syz-executor.4/21648: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.0-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+0xc82/0xcd0 kernel/hung_task.c:295 kthread+0x468/0x490 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 21648 Comm: syz-executor.4 Not tainted 5.15.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__lock_acquire+0x1d6/0x2b00 kernel/locking/lockdep.c:4935 Code: 00 8b 4d 20 48 c7 c0 00 4b 8d 8f 49 29 c6 49 c1 fe 06 48 ba ab aa aa aa aa aa aa aa 49 0f af d6 41 89 d6 85 db 4c 89 7c 24 28 <48> 89 9c 24 88 00 00 00 0f 84 45 01 00 00 83 fb 31 0f 83 56 23 00 RSP: 0018:ffffc90000007a60 EFLAGS: 00000006 RAX: ffffffff8f8d4b00 RBX: 0000000000000005 RCX: 0000000000000000 RDX: 0000000000000042 RSI: dffffc0000000000 RDI: ffff888023bdba00 RBP: ffffc90000007bb0 R08: 0000000000000001 R09: 0000000000000001 R10: fffffbfff1bfcce6 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000002 R14: 0000000000000042 R15: ffff888023bdc458 FS: 00007f7c08b25700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3686b90000 CR3: 000000003d9f6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637 seqcount_lockdep_reader_access+0xfe/0x230 include/linux/seqlock.h:103 ktime_get+0x35/0x2b0 kernel/time/timekeeping.c:827 clockevents_program_event+0xe4/0x320 kernel/time/clockevents.c:326 hrtimer_interrupt+0xbaa/0x1040 kernel/time/hrtimer.c:1824 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0xf9/0x270 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:35 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_local_irq_save arch/x86/include/asm/irqflags.h:106 [inline] RIP: 0010:lock_is_held_type+0x66/0x190 kernel/locking/lockdep.c:5676 Code: 00 65 4c 8b 2c 25 c0 6f 02 00 41 83 bd 5c 0a 00 00 00 0f 85 e6 00 00 00 41 89 f6 49 89 ff 48 c7 04 24 00 00 00 00 9c 8f 04 24 <4c> 8b 24 24 fa 48 c7 c7 00 0c 6f 8a e8 79 11 00 00 65 ff 05 82 5d RSP: 0018:ffffc90005a06458 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 00000000ffffffff RCX: 0000000080000003 RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8cb1d8a0 RBP: ffffc90005a06528 R08: dffffc0000000000 R09: fffffbfff1bfcce6 R10: fffffbfff1bfcce6 R11: 0000000000000000 R12: 0000000000000000 R13: ffff888023bdba00 R14: 00000000ffffffff R15: ffffffff8cb1d8a0 lock_is_held include/linux/lockdep.h:283 [inline] rcu_read_lock_sched_held+0x89/0x130 kernel/rcu/update.c:125 trace_lock_acquire+0x59/0x190 include/trace/events/lock.h:13 lock_acquire+0xa5/0x4d0 kernel/locking/lockdep.c:5608 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:349 [inline] kasan_depopulate_vmalloc_pte+0x16/0x80 mm/kasan/shadow.c:376 apply_to_pte_range mm/memory.c:2518 [inline] apply_to_pmd_range mm/memory.c:2562 [inline] apply_to_pud_range mm/memory.c:2598 [inline] apply_to_p4d_range mm/memory.c:2634 [inline] __apply_to_page_range+0xa04/0xc50 mm/memory.c:2668 kasan_release_vmalloc+0x96/0xb0 mm/kasan/shadow.c:490 __purge_vmap_area_lazy+0xcca/0x18e0 mm/vmalloc.c:1708 try_purge_vmap_area_lazy mm/vmalloc.c:1727 [inline] free_vmap_area_noflush+0x9a1/0xa10 mm/vmalloc.c:1769 free_unmap_vmap_area mm/vmalloc.c:1782 [inline] remove_vm_area+0x1ff/0x220 mm/vmalloc.c:2528 free_vm_area mm/vmalloc.c:3508 [inline] __vmalloc_area_node mm/vmalloc.c:2947 [inline] __vmalloc_node_range+0x43a/0x960 mm/vmalloc.c:3065 vmalloc_user+0x70/0x80 mm/vmalloc.c:3200 vb2_vmalloc_alloc+0xf4/0x330 drivers/media/common/videobuf2/videobuf2-vmalloc.c:47 __vb2_buf_mem_alloc drivers/media/common/videobuf2/videobuf2-core.c:233 [inline] __vb2_queue_alloc+0x78d/0x1410 drivers/media/common/videobuf2/videobuf2-core.c:444 vb2_core_reqbufs+0xae1/0x11f0 drivers/media/common/videobuf2/videobuf2-core.c:838 __vb2_init_fileio+0x2b6/0xbf0 drivers/media/common/videobuf2/videobuf2-core.c:2636 vb2_core_poll+0x2c1/0x700 drivers/media/common/videobuf2/videobuf2-core.c:2465 vb2_poll drivers/media/common/videobuf2/videobuf2-v4l2.c:958 [inline] vb2_fop_poll+0x16c/0x350 drivers/media/common/videobuf2/videobuf2-v4l2.c:1211 v4l2_poll+0x137/0x2a0 drivers/media/v4l2-core/v4l2-dev.c:348 vfs_poll include/linux/poll.h:90 [inline] ep_item_poll fs/eventpoll.c:846 [inline] __ep_eventpoll_poll+0x50b/0x890 fs/eventpoll.c:815 vfs_poll include/linux/poll.h:90 [inline] __io_arm_poll_handler+0x34a/0xb10 fs/io_uring.c:5577 io_poll_add+0x110/0x940 fs/io_uring.c:5844 io_issue_sqe+0x1b61/0x9830 fs/io_uring.c:6639 __io_queue_sqe+0x2d/0x780 fs/io_uring.c:6974 io_queue_sqe fs/io_uring.c:7016 [inline] io_submit_sqe fs/io_uring.c:7219 [inline] io_submit_sqes+0xffc/0xa7c0 fs/io_uring.c:7325 __do_sys_io_uring_enter fs/io_uring.c:10039 [inline] __se_sys_io_uring_enter+0x21f/0x1cb0 fs/io_uring.c:9981 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: 0033:0x7f7c0b5d0ae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f7c08b25188 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f7c0b6e4020 RCX: 00007f7c0b5d0ae9 RDX: 0000000000000000 RSI: 00000000000002ff RDI: 0000000000000003 RBP: 00007f7c0b62af6d R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcc8620aef R14: 00007f7c08b25300 R15: 0000000000022000 ---------------- Code disassembly (best guess): 0: 00 8b 4d 20 48 c7 add %cl,-0x38b7dfb3(%rbx) 6: c0 00 4b rolb $0x4b,(%rax) 9: 8d 8f 49 29 c6 49 lea 0x49c62949(%rdi),%ecx f: c1 fe 06 sar $0x6,%esi 12: 48 ba ab aa aa aa aa movabs $0xaaaaaaaaaaaaaaab,%rdx 19: aa aa aa 1c: 49 0f af d6 imul %r14,%rdx 20: 41 89 d6 mov %edx,%r14d 23: 85 db test %ebx,%ebx 25: 4c 89 7c 24 28 mov %r15,0x28(%rsp) * 2a: 48 89 9c 24 88 00 00 mov %rbx,0x88(%rsp) <-- trapping instruction 31: 00 32: 0f 84 45 01 00 00 je 0x17d 38: 83 fb 31 cmp $0x31,%ebx 3b: 0f .byte 0xf 3c: 83 56 23 00 adcl $0x0,0x23(%rsi)