INFO: task syz-executor.0:8255 blocked for more than 143 seconds. Not tainted 5.9.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:14088 pid: 8255 ppid: 7014 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:3778 [inline] __schedule+0x404/0x8a0 kernel/sched/core.c:4527 schedule+0x37/0xe0 kernel/sched/core.c:4602 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4661 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x472/0x9f0 kernel/locking/mutex.c:1103 __pipe_lock fs/pipe.c:87 [inline] pipe_release+0x1e/0xe0 fs/pipe.c:722 __fput+0xaa/0x250 fs/file_table.c:281 task_work_run+0x68/0xb0 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:140 [inline] exit_to_user_mode_prepare+0x219/0x220 kernel/entry/common.c:167 syscall_exit_to_user_mode+0x7e/0x2e0 kernel/entry/common.c:242 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x415ee1 Code: Bad RIP value. RSP: 002b:00007ffddc019140 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000415ee1 RDX: 0000000000000000 RSI: 00000000007904d0 RDI: 0000000000000006 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 00007ffddc019230 R11: 0000000000000293 R12: 00000000007905a8 R13: 000000000000ae5d R14: ffffffffffffffff R15: 000000000078bfac Showing all locks held in the system: 1 lock held by khungtaskd/1125: #0: ffffffff842f5dc0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x15/0x17a kernel/locking/lockdep.c:5830 1 lock held by in:imklog/6354: #0: ffff88812ab7e6f0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0x45/0x50 fs/file.c:930 1 lock held by syz-executor.0/8255: #0: ffff88810f4c8468 (&pipe->mutex/1){+.+.}-{3:3}, at: __pipe_lock fs/pipe.c:87 [inline] #0: ffff88810f4c8468 (&pipe->mutex/1){+.+.}-{3:3}, at: pipe_release+0x1e/0xe0 fs/pipe.c:722 2 locks held by syz-executor.0/8258: ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1125 Comm: khungtaskd Not tainted 5.9.0-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:77 [inline] dump_stack+0xa3/0xcc lib/dump_stack.c:118 nmi_cpu_backtrace.cold.8+0x3e/0x58 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xd5/0xec 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+0x58e/0x680 kernel/hung_task.c:295 kthread+0x148/0x170 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 8258 Comm: syz-executor.0 Not tainted 5.9.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:iov_iter_alignment+0xee/0x1d0 lib/iov_iter.c:1237 Code: 65 83 75 90 48 09 c8 eb 8b 41 89 f0 45 31 c9 31 c0 41 bb 00 10 00 00 45 85 c0 0f 84 74 ff ff ff 4c 8b 57 18 44 89 c9 44 89 dd <48> c1 e1 04 4c 01 d1 8b 71 08 8b 59 0c 89 f1 01 d3 29 d1 81 e3 ff RSP: 0018:ffffc90002c07cc0 EFLAGS: 00000206 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90002c07e00 RBP: 0000000000001000 R08: 0000000000001000 R09: 0000000000000000 R10: ffff88810f488400 R11: 0000000000001000 R12: 0000000000001000 R13: ffffc90002c07e00 R14: 0000000000000fff R15: 0000000000000000 FS: 00007fb16c128700(0000) GS:ffff88812c000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055b7568f8160 CR3: 000000010f4c3000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_unaligned_io fs/ext4/file.c:174 [inline] ext4_dio_write_iter fs/ext4/file.c:468 [inline] ext4_file_write_iter+0xa7/0x6b0 fs/ext4/file.c:658 call_write_iter include/linux/fs.h:1882 [inline] do_iter_readv_writev+0x166/0x1d0 fs/read_write.c:713 do_iter_write+0x7e/0x1b0 fs/read_write.c:1018 iter_file_splice_write+0x275/0x3c0 fs/splice.c:750 do_splice+0x30c/0x660 fs/splice.c:1144 __do_sys_splice fs/splice.c:1419 [inline] __se_sys_splice fs/splice.c:1401 [inline] __x64_sys_splice+0x8d/0x100 fs/splice.c:1401 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb16c127c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000113 RAX: ffffffffffffffda RBX: 0000000000032240 RCX: 000000000045c369 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 000000000078bff8 R08: 000000000000ffe0 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac R13: 00007ffddc0190cf R14: 00007fb16c1289c0 R15: 000000000078bfac