syzbot


INFO: task hung in lo_open (2)

Status: fixed on 2019/01/15 20:25
Reported-by: syzbot+712350eead2a19b102e9@syzkaller.appspotmail.com
Fix commit: 1dded9acf6dc loop: Avoid circular locking dependency between loop_ctl_mutex and bd_mutex
First crash: 1708d, last: 1479d
similar bugs (5):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-44 INFO: task hung in lo_open syz 593 1095d 1329d 0/2 public: reported syz repro on 2019/04/14 00:02
android-49 INFO: task hung in lo_open C 2683 1095d 1329d 0/3 public: reported C repro on 2019/04/14 09:28
android-414 INFO: task hung in lo_open C 6143 1095d 1332d 0/1 public: reported C repro on 2019/04/11 00:00
linux-4.14 INFO: task hung in lo_open C 1229 19d 1332d 0/1 upstream: reported C repro on 2019/04/11 12:30
upstream INFO: task hung in lo_open 3 1796d 1812d 0/24 closed as invalid on 2018/02/14 14:52

Sample crash report:
netlink: 4 bytes leftover after parsing attributes in process `syz-executor0'.
netlink: 4 bytes leftover after parsing attributes in process `syz-executor0'.
INFO: task syz-executor4:6143 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4   D17648  6143      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 lo_open+0x1b/0xb0 drivers/block/loop.c:1630
 __blkdev_get+0x360/0x13c0 fs/block_dev.c:1482
 blkdev_get+0xc1/0xb50 fs/block_dev.c:1617
 blkdev_open+0x1fb/0x280 fs/block_dev.c:1775
 do_dentry_open+0x499/0x1250 fs/open.c:771
 vfs_open+0xa0/0xd0 fs/open.c:880
 do_last fs/namei.c:3418 [inline]
 path_openat+0x12bc/0x5150 fs/namei.c:3534
 do_filp_open+0x255/0x380 fs/namei.c:3564
 do_sys_open+0x568/0x700 fs/open.c:1063
 __do_sys_open fs/open.c:1081 [inline]
 __se_sys_open fs/open.c:1076 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1076
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411180
Code: 89 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 48 b8 ff ff ff ff 7f 00 00 00 48 89 d6 31 d2 48 f7 f3 48 89 f2 eb b9 48 8d 05 9e bb <3f> 00 48 89 04 24 48 8d 05 93 7a 56 00 48 89 44 24 08 e8 09 9e 01
RSP: 002b:00007ffff1551e28 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000411180
RDX: 00007ffff1551e9a RSI: 0000000000000002 RDI: 00007ffff1551e90
RBP: 0000000000001a6f R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000a
R13: 00000000000eb400 R14: 0000000000000841 R15: 0000000000000004
INFO: task syz-executor5:6182 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D15224  6182      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 lo_open+0x1b/0xb0 drivers/block/loop.c:1630
 __blkdev_get+0x360/0x13c0 fs/block_dev.c:1482
 blkdev_get+0xc1/0xb50 fs/block_dev.c:1617
 blkdev_open+0x1fb/0x280 fs/block_dev.c:1775
 do_dentry_open+0x499/0x1250 fs/open.c:771
 vfs_open+0xa0/0xd0 fs/open.c:880
 do_last fs/namei.c:3418 [inline]
 path_openat+0x12bc/0x5150 fs/namei.c:3534
 do_filp_open+0x255/0x380 fs/namei.c:3564
 do_sys_open+0x568/0x700 fs/open.c:1063
 __do_sys_open fs/open.c:1081 [inline]
 __se_sys_open fs/open.c:1076 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1076
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411180
Code: 89 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 48 b8 ff ff ff ff 7f 00 00 00 48 89 d6 31 d2 48 f7 f3 48 89 f2 eb b9 48 8d 05 9e bb <3f> 00 48 89 04 24 48 8d 05 93 7a 56 00 48 89 44 24 08 e8 09 9e 01
RSP: 002b:00007ffef2b100f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000411180
RDX: 00007ffef2b1016a RSI: 0000000000000002 RDI: 00007ffef2b10160
RBP: 00000000000011b8 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000c
R13: 00000000000eb3b3 R14: 000000000000066f R15: 0000000000000005
INFO: task syz-executor2:10706 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor2   D14792 10706      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 lo_open+0x1b/0xb0 drivers/block/loop.c:1630
 __blkdev_get+0x360/0x13c0 fs/block_dev.c:1482
 blkdev_get+0xc1/0xb50 fs/block_dev.c:1617
 blkdev_open+0x1fb/0x280 fs/block_dev.c:1775
 do_dentry_open+0x499/0x1250 fs/open.c:771
 vfs_open+0xa0/0xd0 fs/open.c:880
 do_last fs/namei.c:3418 [inline]
 path_openat+0x12bc/0x5150 fs/namei.c:3534
 do_filp_open+0x255/0x380 fs/namei.c:3564
 do_sys_open+0x568/0x700 fs/open.c:1063
 __do_sys_open fs/open.c:1081 [inline]
 __se_sys_open fs/open.c:1076 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1076
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411180
Code: 89 44 24 40 48 8b 6c 24 20 48 83 c4 28 c3 48 b8 ff ff ff ff 7f 00 00 00 48 89 d6 31 d2 48 f7 f3 48 89 f2 eb b9 48 8d 05 9e bb <3f> 00 48 89 04 24 48 8d 05 93 7a 56 00 48 89 44 24 08 e8 09 9e 01
RSP: 002b:00007fffb0e819f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000411180
RDX: 00007fffb0e81a6a RSI: 0000000000000002 RDI: 00007fffb0e81a60
RBP: 0000000000000458 R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 0000000000000007
R13: 00000000000eb37e R14: 00000000000000ff R15: 0000000000000002
INFO: task syz-executor1:12138 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor1   D18600 12138      1 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 lo_open+0x1b/0xb0 drivers/block/loop.c:1630
 __blkdev_get+0x360/0x13c0 fs/block_dev.c:1482
 blkdev_get+0xc1/0xb50 fs/block_dev.c:1617
 blkdev_open+0x1fb/0x280 fs/block_dev.c:1775
 do_dentry_open+0x499/0x1250 fs/open.c:771
 vfs_open+0xa0/0xd0 fs/open.c:880
 do_last fs/namei.c:3418 [inline]
 path_openat+0x12bc/0x5150 fs/namei.c:3534
 do_filp_open+0x255/0x380 fs/namei.c:3564
 do_sys_open+0x568/0x700 fs/open.c:1063
 __do_sys_open fs/open.c:1081 [inline]
 __se_sys_open fs/open.c:1076 [inline]
 __x64_sys_open+0x7e/0xc0 fs/open.c:1076
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411180
Code: 40 00 b9 e0 94 65 00 ba c4 31 44 00 be c6 31 44 00 bf bc 31 44 00 ff 15 f6 80 24 00 85 c0 41 89 c6 74 3b 44 89 f1 ba 00 33 44 <00> 44 89 f6 31 ff 31 c0 ff 15 aa 82 24 00 e9 90 fc ff ff c6 02 00
RSP: 002b:00007ffd64ec9b58 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000411180
RDX: 00007ffd64ec9bca RSI: 0000000000000002 RDI: 00007ffd64ec9bc0
RBP: 000000000000048b R08: 0000000000000000 R09: 000000000000000a
R10: 0000000000000075 R11: 0000000000000246 R12: 000000000000000b
R13: 00000000000eb397 R14: 0000000000000132 R15: 0000000000000001
INFO: task syz-executor3:19875 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D25208 19875   6109 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 loop_control_ioctl+0x91/0x530 drivers/block/loop.c:1997
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: Bad RIP value.
RSP: 002b:00007f38dc86fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000000004c82 RDI: 0000000000000004
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f38dc8706d4
R13: 00000000004c0619 R14: 00000000004d0b28 R15: 00000000ffffffff
INFO: task syz-executor3:19877 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D26680 19877   6109 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 loop_control_ioctl+0x91/0x530 drivers/block/loop.c:1997
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: Bad RIP value.
RSP: 002b:00007f38dc84ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000457569
RDX: 0000000000000000 RSI: 0000000000004c82 RDI: 0000000000000004
RBP: 000000000072c040 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f38dc84f6d4
R13: 00000000004c0619 R14: 00000000004d0b28 R15: 00000000ffffffff
INFO: task syz-executor3:19878 blocked for more than 140 seconds.
      Not tainted 4.20.0-rc2+ #334
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor3   D25992 19878   6109 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2831 [inline]
 __schedule+0x8cf/0x21d0 kernel/sched/core.c:3472
 schedule+0xfe/0x460 kernel/sched/core.c:3516
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3574
 __mutex_lock_common kernel/locking/mutex.c:1002 [inline]
 __mutex_lock+0xaff/0x16f0 kernel/locking/mutex.c:1072
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1087
 loop_control_ioctl+0x91/0x530 drivers/block/loop.c:1997
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:509 [inline]
 do_vfs_ioctl+0x1de/0x1790 fs/ioctl.c:696
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:713
 __do_sys_ioctl fs/ioctl.c:720 [inline]
 __se_sys_ioctl fs/ioctl.c:718 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457569
Code: Bad RIP value.
RSP: 002b:00007f38dc82dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569
RDX: 0000000020000800 RSI: 0000000081009431 RDI: 0000000000000004
RBP: 000000000072c0e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f38dc82e6d4
R13: 00000000004bf93f R14: 00000000004cfb98 R15: 00000000ffffffff

Showing all locks held in the system:
1 lock held by kworker/0:0H/6:
 #0: 000000001cb2bab7 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1126 [inline]
 #0: 000000001cb2bab7 (&rq->lock){-.-.}, at: __schedule+0x236/0x21d0 kernel/sched/core.c:3410
1 lock held by khungtaskd/1007:
 #0: 00000000c4f50e44 (rcu_read_lock){....}, at: debug_show_all_locks+0xd0/0x424 kernel/locking/lockdep.c:4379
1 lock held by rsyslogd/5914:
 #0: 00000000e0ba3907 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x1bb/0x200 fs/file.c:766
2 locks held by getty/6003:
 #0: 0000000015067d0c (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000d3b15937 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/6004:
 #0: 00000000e16065bf (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 0000000074f34420 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/6005:
 #0: 00000000f8238bde (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000de4a395c (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/6006:
 #0: 0000000038a6e9dc (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000805fd5ff (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/6007:
 #0: 00000000daf16073 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000c2993609 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/6008:
 #0: 0000000094cd254a (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 000000005d17b25d (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by getty/6009:
 #0: 000000008a8bcc21 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x32/0x40 drivers/tty/tty_ldsem.c:353
 #1: 00000000f9a3297b (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x335/0x1e80 drivers/tty/n_tty.c:2154
2 locks held by syz-executor4/6143:
 #0: 00000000ef68730c (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466
 #1: 000000007903b55f (loop_index_mutex){+.+.}, at: lo_open+0x1b/0xb0 drivers/block/loop.c:1630
2 locks held by syz-executor5/6182:
 #0: 00000000d74ce998 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466
 #1: 000000007903b55f (loop_index_mutex){+.+.}, at: lo_open+0x1b/0xb0 drivers/block/loop.c:1630
2 locks held by syz-executor2/10706:
 #0: 00000000539187df (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466
 #1: 000000007903b55f (loop_index_mutex){+.+.}, at: lo_open+0x1b/0xb0 drivers/block/loop.c:1630
2 locks held by syz-executor1/12138:
 #0: 00000000cd40befd (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x19b/0x13c0 fs/block_dev.c:1466
 #1: 000000007903b55f (loop_index_mutex){+.+.}, at: lo_open+0x1b/0xb0 drivers/block/loop.c:1630
1 lock held by syz-executor5/16407:
 #0: 000000006d22a9f4 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 fs/exec.c:1404
1 lock held by syz-executor5/16453:
 #0: 00000000df9e1900 (&sig->cred_guard_mutex){+.+.}, at: prepare_bprm_creds+0x53/0x120 fs/exec.c:1404
2 locks held by syz-executor3/19871:
1 lock held by syz-executor3/19875:
 #0: 000000007903b55f (loop_index_mutex){+.+.}, at: loop_control_ioctl+0x91/0x530 drivers/block/loop.c:1997
1 lock held by syz-executor3/19877:
 #0: 000000007903b55f (loop_index_mutex){+.+.}, at: loop_control_ioctl+0x91/0x530 drivers/block/loop.c:1997
1 lock held by syz-executor3/19878:
 #0: 000000007903b55f (loop_index_mutex){+.+.}, at: loop_control_ioctl+0x91/0x530 drivers/block/loop.c:1997

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 1007 Comm: khungtaskd Not tainted 4.20.0-rc2+ #334
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+0x244/0x39d lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.2+0x5c/0xa1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1e8/0x22a 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:205 [inline]
 watchdog+0xb51/0x1060 kernel/hung_task.c:289
 kthread+0x35a/0x440 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57

Crashes (10):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce-root 2018/11/15 09:10 upstream d41217aac0a5 5f5f6d14 .config log report
ci-upstream-kasan-gce-selinux-root 2018/11/09 04:05 upstream b00d209241ff e85d2a61 .config log report
ci-upstream-kasan-gce-root 2018/10/15 15:46 upstream 35a7f35ad1b1 caf12900 .config log report
ci-upstream-kasan-gce-selinux-root 2018/10/08 10:00 upstream 0238df646e62 8b311eaf .config log report
ci-upstream-kasan-gce-root 2018/10/04 08:39 upstream cec4de302c5f 8b311eaf .config log report
ci-upstream-kasan-gce-root 2018/04/02 10:30 upstream 0adb32858b0b dc889257 .config log report
ci-upstream-kasan-gce 2018/03/31 16:42 upstream b5dbc28762fd 8fbce0e4 .config log report
ci-upstream-kasan-gce-root 2018/03/31 15:18 upstream b5dbc28762fd 8fbce0e4 .config log report
ci-upstream-linux-next-kasan-gce-root 2018/10/22 20:34 linux-next 8c60c36d0b8c ecb386fe .config log report
ci-upstream-linux-next-kasan-gce-root 2018/09/01 01:18 linux-next a880148cb2af a4718693 .config log report
* Struck through repros no longer work on HEAD.