INFO: task syz-executor.4:7610 blocked for more than 140 seconds.
Not tainted 5.0.0-rc7-next-20190222 #41
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4 D23200 7610 1 0x00000004
Call Trace:
context_switch kernel/sched/core.c:2877 [inline]
__schedule+0x817/0x1cc0 kernel/sched/core.c:3518
schedule+0x92/0x180 kernel/sched/core.c:3562
__rwsem_down_write_failed_common kernel/locking/rwsem-xadd.c:582 [inline]
rwsem_down_write_failed+0x774/0xc30 kernel/locking/rwsem-xadd.c:611
call_rwsem_down_write_failed+0x17/0x30 arch/x86/lib/rwsem.S:117
__down_write arch/x86/include/asm/rwsem.h:142 [inline]
down_write+0x53/0x90 kernel/locking/rwsem.c:72
inode_lock include/linux/fs.h:763 [inline]
vfs_unlink+0xd1/0x560 fs/namei.c:3989
do_unlinkat+0x3f7/0x6d0 fs/namei.c:4061
__do_sys_unlink fs/namei.c:4108 [inline]
__se_sys_unlink fs/namei.c:4106 [inline]
__x64_sys_unlink+0x42/0x50 fs/namei.c:4106
do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457b77
Code: 44 24 18 48 8b 4c 24 20 48 89 01 48 8b 6c 24 28 48 83 c4 30 c3 e8 49 23 00 00 eb 97 cc cc cc cc cc cc cc 64 48 8b 0c 25 f8 ff <ff> ff 48 3b 61 10 0f 86 b6 00 00 00 48 83 ec 40 48 89 6c 24 38 48
RSP: 002b:00007ffc728b5478 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000457b77
RDX: 00007ffc728b5490 RSI: 00007ffc728b5490 RDI: 00007ffc728b5520
RBP: 0000000000000cb7 R08: 0000000000000000 R09: 0000000000000014
R10: 0000000000000005 R11: 0000000000000246 R12: 00007ffc728b6610
R13: 00000000012ee980 R14: 0000000000000000 R15: 0000000000000004
Showing all locks held in the system:
1 lock held by khungtaskd/1043:
#0: 00000000e3923056 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:4382
1 lock held by rsyslogd/7472:
#0: 00000000b448828b (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801
2 locks held by getty/7563:
#0: 00000000b7eca331 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 000000009bca65f0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7564:
#0: 000000008fe31c11 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 00000000d3ab137e (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7565:
#0: 000000003a9b0e3d (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 000000007537479a (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7566:
#0: 00000000e77320e4 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 0000000074f1cee6 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7567:
#0: 00000000d88fca71 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 00000000d8e39986 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7568:
#0: 000000002f070d42 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 00000000167cff51 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
2 locks held by getty/7569:
#0: 00000000c875263c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:341
#1: 00000000b037be37 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1b70 drivers/tty/n_tty.c:2156
3 locks held by syz-executor.4/7610:
#0: 000000005c697b19 (sb_writers#3){.+.+}, at: sb_start_write include/linux/fs.h:1612 [inline]
#0: 000000005c697b19 (sb_writers#3){.+.+}, at: mnt_want_write+0x3f/0xc0 fs/namespace.c:358
#1: 00000000a276e3db (&type->i_mutex_dir_key#3/1){+.+.}, at: inode_lock_nested include/linux/fs.h:798 [inline]
#1: 00000000a276e3db (&type->i_mutex_dir_key#3/1){+.+.}, at: do_unlinkat+0x29f/0x6d0 fs/namei.c:4047
#2: 000000007a6abb57 (&sb->s_type->i_mutex_key#10){++++}, at: inode_lock include/linux/fs.h:763 [inline]
#2: 000000007a6abb57 (&sb->s_type->i_mutex_key#10){++++}, at: vfs_unlink+0xd1/0x560 fs/namei.c:3989
2 locks held by syz-executor.4/18193:
#0: 000000005c697b19 (sb_writers#3){.+.+}, at: file_start_write include/linux/fs.h:2816 [inline]
#0: 000000005c697b19 (sb_writers#3){.+.+}, at: vfs_write+0x429/0x580 fs/read_write.c:548
#1: 000000007a6abb57 (&sb->s_type->i_mutex_key#10){++++}, at: inode_trylock include/linux/fs.h:783 [inline]
#1: 000000007a6abb57 (&sb->s_type->i_mutex_key#10){++++}, at: ext4_file_write_iter+0x257/0x11a0 fs/ext4/file.c:232
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 1043 Comm: khungtaskd Not tainted 5.0.0-rc7-next-20190222 #41
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+0x172/0x1f0 lib/dump_stack.c:113
nmi_cpu_backtrace.cold+0x63/0xa4 lib/nmi_backtrace.c:101
nmi_trigger_cpumask_backtrace+0x1be/0x236 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:146 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
watchdog+0x9b2/0xeb0 kernel/hung_task.c:288
kthread+0x357/0x430 kernel/kthread.c:253
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0: