INFO: task syz-executor.0:18968 blocked for more than 143 seconds. Not tainted 5.11.0-rc4-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:25144 pid:18968 ppid: 8458 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:4313 [inline] __schedule+0xa4d/0xf80 kernel/sched/core.c:5064 schedule+0x14b/0x200 kernel/sched/core.c:5143 schedule_timeout+0x98/0x2b0 kernel/time/timer.c:1854 do_wait_for_common+0x2dd/0x450 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+0x43/0x50 kernel/sched/completion.c:138 kthread_park+0x10d/0x1c0 kernel/kthread.c:557 io_sq_thread_park fs/io_uring.c:7441 [inline] io_uring_cancel_task_requests fs/io_uring.c:8943 [inline] __io_uring_files_cancel+0x468/0x19e0 fs/io_uring.c:9038 io_uring_files_cancel include/linux/io_uring.h:51 [inline] do_exit+0x2e6/0x2490 kernel/exit.c:780 do_group_exit+0x168/0x2d0 kernel/exit.c:922 get_signal+0x16e5/0x2070 kernel/signal.c:2773 arch_do_signal_or_restart+0x8e/0x6a0 arch/x86/kernel/signal.c:811 handle_signal_work kernel/entry/common.c:147 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0xac/0x1e0 kernel/entry/common.c:201 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x48/0x190 kernel/entry/common.c:302 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45e219 RSP: 002b:00007f5c75453cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 000000000119c030 RCX: 000000000045e219 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 000000000119c034 RBP: 000000000119c028 R08: 0000000000000009 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 000000000119c034 R13: 00007ffca9ba6fbf R14: 00007f5c754549c0 R15: 000000000119c034 Showing all locks held in the system: 1 lock held by khungtaskd/1647: #0: ffffffff8c311580 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30 arch/x86/pci/mmconfig_64.c:151 1 lock held by in:imklog/8131: #0: ffff8880191480f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x24e/0x2f0 fs/file.c:947 1 lock held by syz-executor.0/18968: #0: ffff8880146d2070 (&sqd->lock){+.+.}-{3:3}, at: io_sq_thread_park fs/io_uring.c:7440 [inline] #0: ffff8880146d2070 (&sqd->lock){+.+.}-{3:3}, at: io_uring_cancel_task_requests fs/io_uring.c:8943 [inline] #0: ffff8880146d2070 (&sqd->lock){+.+.}-{3:3}, at: __io_uring_files_cancel+0x447/0x19e0 fs/io_uring.c:9038 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1647 Comm: khungtaskd Not tainted 5.11.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x183/0x22e lib/dump_stack.c:120 nmi_cpu_backtrace+0x16c/0x190 lib/nmi_backtrace.c:105 nmi_trigger_cpumask_backtrace+0x191/0x2f0 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline] watchdog+0xce9/0xd30 kernel/hung_task.c:294 kthread+0x39a/0x3c0 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 8132 Comm: rs:main Q:Reg Not tainted 5.11.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ext4_block_write_begin+0x470/0x12d0 fs/ext4/inode.c:1073 Code: f7 be 08 00 00 00 e8 ff 8c a9 ff 4c 89 f0 48 c1 e8 03 4d 89 fd 49 89 c7 42 80 3c 28 00 74 08 4c 89 f7 e8 43 8b a9 ff 49 8b 1e <48> 89 de 48 83 e6 20 31 ff e8 62 c9 63 ff 48 83 e3 20 0f 85 48 01 RSP: 0018:ffffc9000bdcf6e0 EFLAGS: 00000246 RAX: 1ffff11011d3423a RBX: 0000000000000113 RCX: ffffffff821957e1 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88808e9a11d0 RBP: ffffc9000bdcf810 R08: dffffc0000000000 R09: ffffed1011d3423b R10: ffffed1011d3423b R11: 0000000000000000 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88808e9a11d0 R15: 1ffff11011d3423a FS: 00007f6f79448700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fae2a37a000 CR3: 000000002bcff000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_da_write_begin+0x7a5/0x10c0 fs/ext4/inode.c:3016 generic_perform_write+0x28c/0x540 mm/filemap.c:3408 ext4_buffered_write_iter+0x41c/0x590 fs/ext4/file.c:270 ext4_file_write_iter+0x902/0x1b70 fs/ext4/file.c:503 call_write_iter include/linux/fs.h:1901 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0xa39/0xc90 fs/read_write.c:605 ksys_write+0x171/0x2a0 fs/read_write.c:658 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f6f7be8c1cd Code: c2 20 00 00 75 10 b8 01 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae fc ff ff 48 89 04 24 b8 01 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 f7 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007f6f79447590 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f6f70022e50 RCX: 00007f6f7be8c1cd RDX: 00000000000007e5 RSI: 00007f6f70022e50 RDI: 0000000000000006 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 00007f6f70022bd0 R13: 00007f6f794475b0 R14: 000055d9496a1360 R15: 00000000000007e5