INFO: task syz-executor3:20815 blocked for more than 120 seconds. Not tainted 4.17.0-rc5+ #59 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor3 D20152 20815 4604 0x00000004 Call Trace: context_switch kernel/sched/core.c:2859 [inline] __schedule+0x801/0x1e30 kernel/sched/core.c:3501 schedule+0xef/0x430 kernel/sched/core.c:3545 io_schedule+0x1c/0x70 kernel/sched/core.c:5165 __blkdev_direct_IO_simple+0x7fc/0xfb0 fs/block_dev.c:241 blkdev_direct_IO+0xb5f/0x1100 fs/block_dev.c:428 generic_file_read_iter+0x510/0x2f00 mm/filemap.c:2341 blkdev_read_iter+0x120/0x190 fs/block_dev.c:1930 call_read_iter include/linux/fs.h:1778 [inline] generic_file_splice_read+0x552/0x910 fs/splice.c:307 do_splice_to+0x12e/0x190 fs/splice.c:880 splice_direct_to_actor+0x268/0x8d0 fs/splice.c:952 do_splice_direct+0x2cc/0x400 fs/splice.c:1061 do_sendfile+0x60f/0xe00 fs/read_write.c:1440 __do_sys_sendfile64 fs/read_write.c:1495 [inline] __se_sys_sendfile64 fs/read_write.c:1487 [inline] __x64_sys_sendfile64+0x155/0x240 fs/read_write.c:1487 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x455a09 RSP: 002b:00007f0991a00c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f0991a016d4 RCX: 0000000000455a09 RDX: 0000000020000040 RSI: 0000000000000013 RDI: 0000000000000013 RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 000000001b7889b2 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000579 R14: 00000000006fc3f8 R15: 0000000000000000 Showing all locks held in the system: 2 locks held by khungtaskd/893: #0: 00000000384f6bf0 (rcu_read_lock){....}, at: check_hung_uninterruptible_tasks kernel/hung_task.c:175 [inline] #0: 00000000384f6bf0 (rcu_read_lock){....}, at: watchdog+0x1ff/0xf60 kernel/hung_task.c:249 #1: 00000000c24bfcc4 (tasklist_lock){.+.+}, at: debug_show_all_locks+0xde/0x34a kernel/locking/lockdep.c:4470 2 locks held by getty/4524: #0: 00000000eb00047e (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 000000002265e48e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4525: #0: 00000000fa63b129 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000e7f5df13 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4526: #0: 00000000e15e70cc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000ebc4456a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4527: #0: 0000000093ba10bb (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000668db3e8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4528: #0: 00000000c2a4b229 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000c03c065a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4529: #0: 00000000397385e8 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 00000000a11a73b5 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 2 locks held by getty/4530: #0: 00000000eb3661a5 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40 drivers/tty/tty_ldsem.c:365 #1: 0000000088b99944 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x321/0x1cc0 drivers/tty/n_tty.c:2131 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 893 Comm: khungtaskd Not tainted 4.17.0-rc5+ #59 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+0x1b9/0x294 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.4+0x19/0xce lib/nmi_backtrace.c:103 nmi_trigger_cpumask_backtrace+0x151/0x192 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_all_cpu_backtrace include/linux/nmi.h:138 [inline] check_hung_task kernel/hung_task.c:132 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:190 [inline] watchdog+0xc10/0xf60 kernel/hung_task.c:249 kthread+0x345/0x410 kernel/kthread.c:240 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 4432 Comm: rs:main Q:Reg Not tainted 4.17.0-rc5+ #59 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ext4_data_block_valid+0x1cf/0x340 fs/ext4/block_validity.c:211 RSP: 0018:ffff8801b0546be0 EFLAGS: 00000246 RAX: 1ffff1003988f9df RBX: ffff8801cc47cee0 RCX: ffffffff81fe9113 RDX: 0000000000000000 RSI: ffffffff81fe90af RDI: ffff8801cc47cef8 RBP: ffff8801b0546c18 R08: ffff8801aff04500 R09: 0000000000000000 R10: ffffed003b5e46c2 R11: ffff8801daf23613 R12: 0000000000018000 R13: 0000000000028120 R14: dffffc0000000000 R15: ffff8801cc428400 FS: 00007f1db2a5d700(0000) GS:ffff8801daf00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 00000001b1a8e000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_valid_extent fs/ext4/extents.c:380 [inline] ext4_valid_extent_entries fs/ext4/extents.c:410 [inline] __ext4_ext_check+0xc69/0x1340 fs/ext4/extents.c:465 ext4_ext_remove_space+0x1898/0x4b60 fs/ext4/extents.c:2934 ext4_ext_truncate+0x1d1/0x220 fs/ext4/extents.c:4638 ext4_truncate+0xecd/0x1640 fs/ext4/inode.c:4463 ext4_truncate_failed_write fs/ext4/truncate.h:16 [inline] ext4_da_write_begin+0x7a4/0x1260 fs/ext4/inode.c:3094 generic_perform_write+0x39a/0x6a0 mm/filemap.c:3139 __generic_file_write_iter+0x26e/0x630 mm/filemap.c:3264 ext4_file_write_iter+0x388/0x1420 fs/ext4/file.c:266 call_write_iter include/linux/fs.h:1784 [inline] new_sync_write fs/read_write.c:474 [inline] __vfs_write+0x64d/0x960 fs/read_write.c:487 vfs_write+0x1f8/0x560 fs/read_write.c:549 ksys_write+0xf9/0x250 fs/read_write.c:598 __do_sys_write fs/read_write.c:610 [inline] __se_sys_write fs/read_write.c:607 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:607 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f1db44bb19d RSP: 002b:00007f1db2a5beb0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 000000000000016c RCX: 00007f1db44bb19d RDX: 000000000000016c RSI: 0000000002663a90 RDI: 0000000000000005 RBP: 0000000002663a90 R08: 0000000002663ba1 R09: 00007f1db3e38dc7 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 00007f1db2a5c330 R14: 0000000000000004 R15: 0000000002663890 Code: 3c 01 00 00 48 8b 5b 10 e8 4f 9e 7a ff 48 85 db 0f 84 9f 00 00 00 e8 41 9e 7a ff 48 8d 7b 18 48 89 f8 48 c1 e8 03 42 80 3c 30 00 <0f> 85 05 01 00 00 4c 8b 63 18 48 8b 75 d0 4c 89 e7 e8 cb 9e 7a