syzbot


INFO: task hung in debugfs_remove_recursive

Status: auto-closed as invalid on 2019/03/28 15:11
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+5c613d04b8d3e9203888@syzkaller.appspotmail.com
First crash: 2034d, last: 2034d

Sample crash report:
INFO: task syz-executor5:8561 blocked for more than 140 seconds.
      Not tainted 4.19.0-rc5-next-20180928+ #84
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D23096  8561   6183 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2830 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3479
 schedule+0xfe/0x460 kernel/sched/core.c:3523
 __rwsem_down_write_failed_common+0xbbc/0x15e0 kernel/locking/rwsem-xadd.c:577
 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606
 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+0xa5/0x130 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:745 [inline]
 debugfs_remove_recursive+0x2cf/0x530 fs/debugfs/inode.c:754
 kvm_destroy_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:584 [inline]
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:732 [inline]
 kvm_put_kvm+0x1c6/0xff0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:772
 kvm_vcpu_release+0x7b/0xa0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2406
 __fput+0x3bc/0xa70 fs/file_table.c:279
 ____fput+0x15/0x20 fs/file_table.c:312
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411051
Code: 00 00 00 e8 91 a8 01 00 0f 0b e8 1a 8f 04 00 e9 c5 fe ff ff cc cc cc cc cc 64 48 8b 0c 25 f8 ff ff ff 48 3b 61 10 76 3d 48 83 <ec> 28 48 89 6c 24 20 48 8d 6c 24 20 48 8b 44 24 30 48 8b 08 48 89
RSP: 002b:00007ffc41be5ab0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000411051
RDX: 0000000000000000 RSI: 00000000007314f0 RDI: 0000000000000006
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 00007ffc41be59e0 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000001 R14: 000000000000001d R15: 0000000000000005
INFO: task syz-executor5:8573 blocked for more than 140 seconds.
      Not tainted 4.19.0-rc5-next-20180928+ #84
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor5   D21048  8573   6183 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2830 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3479
 schedule+0xfe/0x460 kernel/sched/core.c:3523
 __rwsem_down_write_failed_common+0xbbc/0x15e0 kernel/locking/rwsem-xadd.c:577
 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606
 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+0xa5/0x130 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:745 [inline]
 start_creating+0xb1/0x200 fs/debugfs/inode.c:309
 debugfs_create_dir+0x23/0x3c0 fs/debugfs/inode.c:507
 kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:603 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3213 [inline]
 kvm_dev_ioctl+0x963/0x1ae0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3240
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 6a 60 09 01 87 01 8b 05 62 60 09 01 83 f8 01 0f 85 8a 00 <00> 00 b8 01 00 00 00 88 05 9e 65 09 01 84 c0 74 72 b8 01 00 00 00
RSP: 002b:00007fb6dd997c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 000000000000000a
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fb6dd9986d4
R13: 00000000004bfc2e R14: 00000000004cfcb8 R15: 00000000ffffffff
INFO: task syz-executor4:8613 blocked for more than 140 seconds.
      Not tainted 4.19.0-rc5-next-20180928+ #84
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4   D24448  8613   6153 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2830 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3479
 schedule+0xfe/0x460 kernel/sched/core.c:3523
 __rwsem_down_write_failed_common+0xbbc/0x15e0 kernel/locking/rwsem-xadd.c:577
 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606
 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+0xa5/0x130 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:745 [inline]
 start_creating+0xb1/0x200 fs/debugfs/inode.c:309
 debugfs_create_dir+0x23/0x3c0 fs/debugfs/inode.c:507
 kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:603 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3213 [inline]
 kvm_dev_ioctl+0x963/0x1ae0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3240
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 6a 60 09 01 87 01 8b 05 62 60 09 01 83 f8 01 0f 85 8a 00 <00> 00 b8 01 00 00 00 88 05 9e 65 09 01 84 c0 74 72 b8 01 00 00 00
RSP: 002b:00007fc657388c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000003
RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc6573896d4
R13: 00000000004bfc2e R14: 00000000004cfcb8 R15: 00000000ffffffff
INFO: task syz-executor4:8617 blocked for more than 140 seconds.
      Not tainted 4.19.0-rc5-next-20180928+ #84
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor4   D24520  8617   6153 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2830 [inline]
 __schedule+0x86c/0x1ed0 kernel/sched/core.c:3479
 schedule+0xfe/0x460 kernel/sched/core.c:3523
 __rwsem_down_write_failed_common+0xbbc/0x15e0 kernel/locking/rwsem-xadd.c:577
 rwsem_down_write_failed+0xe/0x10 kernel/locking/rwsem-xadd.c:606
 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+0xa5/0x130 kernel/locking/rwsem.c:72
 inode_lock include/linux/fs.h:745 [inline]
 start_creating+0xb1/0x200 fs/debugfs/inode.c:309
 debugfs_create_dir+0x23/0x3c0 fs/debugfs/inode.c:507
 kvm_create_vm_debugfs arch/x86/kvm/../../../virt/kvm/kvm_main.c:603 [inline]
 kvm_dev_ioctl_create_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:3213 [inline]
 kvm_dev_ioctl+0x963/0x1ae0 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3240
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:501 [inline]
 do_vfs_ioctl+0x1de/0x1720 fs/ioctl.c:685
 ksys_ioctl+0xa9/0xd0 fs/ioctl.c:702
 __do_sys_ioctl fs/ioctl.c:709 [inline]
 __se_sys_ioctl fs/ioctl.c:707 [inline]
 __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:707
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457579
Code: 24 08 48 89 01 e8 d7 2d fc ff e8 22 7a fc ff b8 02 00 00 00 48 8d 0d 6a 60 09 01 87 01 8b 05 62 60 09 01 83 f8 01 0f 85 8a 00 <00> 00 b8 01 00 00 00 88 05 9e 65 09 01 84 c0 74 72 b8 01 00 00 00
RSP: 002b:00007fc657367c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457579
RDX: 0000000000000000 RSI: 000000000000ae01 RDI: 0000000000000008
RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc6573686d4
R13: 00000000004bfc2e R14: 00000000004cfcb8 R15: 00000000ffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 981 Comm: khungtaskd Not tainted 4.19.0-rc5-next-20180928+ #84
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+0x1d3/0x2c4 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold.4+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1c2/0x22c 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:144 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:204 [inline]
 watchdog+0xb39/0x1050 kernel/hung_task.c:265
 kthread+0x35a/0x440 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt+0x6/0x10 arch/x86/include/asm/irqflags.h:57

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2018/09/29 15:10 linux-next 4794a36bf08d 41e4b329 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.