INFO: task syz-executor.5:18765 blocked for more than 140 seconds. Not tainted 4.14.108+ #36 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D25496 18765 20672 0x00000004 Call Trace: schedule+0x92/0x1c0 kernel/sched/core.c:3498 __rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:572 [inline] rwsem_down_write_failed+0x3b1/0x760 kernel/locking/rwsem-xadd.c:601 call_rwsem_down_write_failed+0x13/0x20 arch/x86/lib/rwsem.S:105 __down_write arch/x86/include/asm/rwsem.h:126 [inline] down_write+0x4f/0x90 kernel/locking/rwsem.c:56 inode_lock include/linux/fs.h:715 [inline] ext4_file_write_iter+0x1fe/0xe10 fs/ext4/file.c:233 call_write_iter include/linux/fs.h:1784 [inline] do_iter_readv_writev+0x379/0x580 fs/read_write.c:678 do_iter_write fs/read_write.c:957 [inline] do_iter_write+0x152/0x550 fs/read_write.c:938 vfs_iter_write+0x70/0xa0 fs/read_write.c:970 iter_file_splice_write+0x560/0xa50 fs/splice.c:749 do_splice_from fs/splice.c:851 [inline] direct_splice_actor+0x118/0x160 fs/splice.c:1018 splice_direct_to_actor+0x292/0x760 fs/splice.c:973 do_splice_direct+0x177/0x240 fs/splice.c:1061 do_sendfile+0x493/0xb20 fs/read_write.c:1438 SYSC_sendfile64 fs/read_write.c:1493 [inline] SyS_sendfile64+0xab/0x140 fs/read_write.c:1485 do_syscall_64+0x19b/0x4b0 arch/x86/entry/common.c:289 Showing all locks held in the system: 1 lock held by khungtaskd/23: #0: (tasklist_lock){.+.+}, at: [] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4541 1 lock held by rsyslogd/1631: #0: (&f->f_pos_lock){+.+.}, at: [] __fdget_pos+0xa6/0xc0 fs/file.c:768 2 locks held by getty/1758: #0: (&tty->ldisc_sem){++++}, at: [] tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:275 #1: (&ldata->atomic_read_lock){+.+.}, at: [] n_tty_read+0x1f7/0x1700 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.5/18765: #0: (sb_writers#4){.+.+}, at: [] file_start_write include/linux/fs.h:2726 [inline] #0: (sb_writers#4){.+.+}, at: [] do_sendfile+0x88f/0xb20 fs/read_write.c:1437 #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] inode_lock include/linux/fs.h:715 [inline] #1: (&sb->s_type->i_mutex_key#9){++++}, at: [] ext4_file_write_iter+0x1fe/0xe10 fs/ext4/file.c:233 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 23 Comm: khungtaskd Not tainted 4.14.108+ #36 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0xb9/0x10e lib/dump_stack.c:53 nmi_cpu_backtrace.cold+0x47/0x86 lib/nmi_backtrace.c:101 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 27612 Comm: syz-executor.3 Not tainted 4.14.108+ #36 task: ffff8881c3b7af00 task.stack: ffff888186c50000 RIP: 0033:0x4015a4 RSP: 002b:00007f0bc65fd690 EFLAGS: 00000282 RAX: 00000000a4cefeb5 RBX: 000000000000000b RCX: 0000000000458209 RDX: 0000000000000000 RSI: 00007f0bc65fd6c0 RDI: 000000000000000b RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 13fef87655499591 R13: 969e55760c01ed22 R14: 4a8849d4ed6af117 R15: 78f7875e6c3e21bd FS: 00007f0bc65fe700(0000) GS:ffff8881dba00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000c42f9f7010 CR3: 00000001c7b30004 CR4: 00000000001606b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600