syzbot


INFO: task hung in exit_signals

Status: auto-closed as invalid on 2020/03/16 09:13
Reported-by: syzbot+64ee1b39a9b33405d122@syzkaller.appspotmail.com
First crash: 1783d, last: 1783d

Sample crash report:
SELinux: unrecognized netlink message: protocol=9 nlmsg_type=52015 sclass=netlink_audit_socket pig=2293 comm=syz-executor.4
audit: type=1107 audit(1573981711.360:16127): pid=2291 uid=0 auid=4294967295 ses=4294967295 subj=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 msg='  
'
INFO: task syz-executor.2:27738 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28656 27738  24583 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x41447a
RSP: 002b:00007ffc67a34348 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000006c5d RCX: 000000000041447a
RDX: 0000000040000000 RSI: 00007ffc67a34354 RDI: ffffffffffffffff
RBP: 00000000000000f8 R08: 0000000000006c5a R09: 000000000167c940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000416140
R13: 00007ffc67a345d8 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.3:27742 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.3  D28656 27742   7244 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x41447a
RSP: 002b:00007ffff2b4db08 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000006c5f RCX: 000000000041447a
RDX: 0000000040000000 RSI: 00007ffff2b4db14 RDI: ffffffffffffffff
RBP: 00000000000000f8 R08: 0000000000006c5e R09: 00000000012ff940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000416140
R13: 00007ffff2b4dd98 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.5:27744 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.5  D28656 27744   6848 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x41447a
RSP: 002b:00007ffca0a2f4d8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000006c61 RCX: 000000000041447a
RDX: 0000000040000000 RSI: 00007ffca0a2f4e4 RDI: ffffffffffffffff
RBP: 00000000000000f8 R08: 0000000000006c60 R09: 0000000001d32940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000416140
R13: 00007ffca0a2f768 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.1:27786 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.1  D28656 27786   6856 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x41447a
RSP: 002b:00007ffd646fc898 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000006c8b RCX: 000000000041447a
RDX: 0000000040000000 RSI: 00007ffd646fc8a4 RDI: ffffffffffffffff
RBP: 00000000000000f8 R08: 0000000000006c8a R09: 0000000000c2f940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000416140
R13: 00007ffd646fcb28 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.4:27887 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.4  D28656 27887   6856 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x41447a
RSP: 002b:00007ffe90725668 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000006cf0 RCX: 000000000041447a
RDX: 0000000040000000 RSI: 00007ffe90725674 RDI: ffffffffffffffff
RBP: 00000000000000f8 R08: 0000000000006cef R09: 0000000002891940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000416140
R13: 00007ffe907258f8 R14: 0000000000000000 R15: 0000000000000000
INFO: task syz-executor.0:27889 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28656 27889   6856 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x41447a
RSP: 002b:00007fff58274ba8 EFLAGS: 00000246 ORIG_RAX: 000000000000003d
RAX: fffffffffffffe00 RBX: 0000000000006cf2 RCX: 000000000041447a
RDX: 0000000040000000 RSI: 00007fff58274bb4 RDI: ffffffffffffffff
RBP: 00000000000000f8 R08: 0000000000006cf1 R09: 0000000002492940
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000416140
R13: 00007fff58274e38 R14: 0000000000000000 R15: 0000000000000000
INFO: task udevd:30735 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
udevd           D27568 30735   3540 0x00000000
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 copy_process.part.0+0x670d/0x6a00 kernel/fork.c:1852
 copy_process kernel/fork.c:1595 [inline]
 _do_fork+0x19e/0xce0 kernel/fork.c:2085
 SYSC_clone kernel/fork.c:2195 [inline]
 SyS_clone+0x37/0x50 kernel/fork.c:2189
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x7f109e7d0f46
RSP: 002b:00007ffde4ceac40 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007ffde4ceac40 RCX: 00007f109e7d0f46
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 00007ffde4ceaca0 R08: 000000000000780f R09: 000000000000780f
R10: 00007f109f0eda70 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffde4ceac60 R14: 0000000000000005 R15: 0000000000000005
INFO: task syz-executor.2:2279 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28528  2279  27741 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 copy_process.part.0+0x670d/0x6a00 kernel/fork.c:1852
 copy_process kernel/fork.c:1595 [inline]
 _do_fork+0x19e/0xce0 kernel/fork.c:2085
 SYSC_clone kernel/fork.c:2195 [inline]
 SyS_clone+0x37/0x50 kernel/fork.c:2189
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45d009
RSP: 002b:00007ffc67a33e88 EFLAGS: 00000202 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f703b5df700 RCX: 000000000045d009
RDX: 00007f703b5df9d0 RSI: 00007f703b5dedb0 RDI: 00000000003d0f00
RBP: 00007ffc67a340a0 R08: 00007f703b5df700 R09: 00007f703b5df700
R10: 00007f703b5df9d0 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffc67a33f3f R14: 00007f703b5df9c0 R15: 000000000075c07c
INFO: task syz-executor.2:2283 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D29584  2283  27741 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a639
RSP: 002b:00007f703b620c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: 0000000000010000 RBX: 0000000000000003 RCX: 000000000045a639
RDX: 00000000fffffef3 RSI: 00000000200001c0 RDI: 0000000000000004
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f703b6216d4
R13: 00000000004c7120 R14: 00000000004e2678 R15: 00000000ffffffff
INFO: task syz-executor.2:2296 blocked for more than 140 seconds.
      Not tainted 4.14.154 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28896  2296  27741 0x80000004
Call Trace:
 context_switch kernel/sched/core.c:2808 [inline]
 __schedule+0x7b8/0x1cd0 kernel/sched/core.c:3384
 schedule+0x92/0x1c0 kernel/sched/core.c:3428
 __rwsem_down_read_failed_common kernel/locking/rwsem-xadd.c:292 [inline]
 rwsem_down_read_failed+0x1f6/0x390 kernel/locking/rwsem-xadd.c:309
 call_rwsem_down_read_failed+0x18/0x30 arch/x86/lib/rwsem.S:94
 __down_read arch/x86/include/asm/rwsem.h:66 [inline]
 __percpu_down_read kernel/locking/percpu-rwsem.c:85 [inline]
 __percpu_down_read+0x83/0xf0 kernel/locking/percpu-rwsem.c:41
 percpu_down_read_preempt_disable include/linux/percpu-rwsem.h:49 [inline]
 percpu_down_read include/linux/percpu-rwsem.h:59 [inline]
 cgroup_threadgroup_change_begin include/linux/cgroup-defs.h:624 [inline]
 exit_signals+0x4bf/0x750 kernel/signal.c:2494
 do_exit+0x213/0x2c10 kernel/exit.c:820
 do_group_exit+0x111/0x330 kernel/exit.c:977
 get_signal+0x381/0x1cd0 kernel/signal.c:2409
 do_signal+0x86/0x19a0 arch/x86/kernel/signal.c:814
 exit_to_usermode_loop+0x15c/0x220 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4bc/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a639
RSP: 002b:00007f703b5ffcf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000075bfd0 RCX: 000000000045a639
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000075bfd0
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000075bfd4
R13: 00007ffc67a33f3f R14: 00007f703b6009c0 R15: 000000000075bfd4

Showing all locks held in the system:
1 lock held by kworker/dying/18:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by khungtaskd/1017:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8148bb78>] debug_show_all_locks+0x7f/0x21f kernel/locking/lockdep.c:4544
2 locks held by getty/6824:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6825:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6826:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6827:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6828:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6829:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
2 locks held by getty/6830:
 #0:  (&tty->ldisc_sem){++++}, at: [<ffffffff861ce8d3>] ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:376
 #1:  (&ldata->atomic_read_lock){+.+.}, at: [<ffffffff83114c06>] n_tty_read+0x1e6/0x17b0 drivers/tty/n_tty.c:2156
1 lock held by kworker/dying/6881:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by kworker/dying/27661:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.2/27738:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.3/27742:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.5/27744:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.1/27786:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.4/27887:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.0/27889:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by udevd/30735:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085
1 lock held by syz-executor.2/2279:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085
1 lock held by syz-executor.2/2283:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.2/2296:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.5/2281:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085
1 lock held by syz-executor.0/2284:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085
1 lock held by syz-executor.1/2286:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085
1 lock held by syz-executor.1/2292:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff81389a33>] do_exit+0x213/0x2c10 kernel/exit.c:820
1 lock held by syz-executor.4/2291:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085
1 lock held by kvm-nx-lpage-re/2299:
 #0:  (cgroup_mutex){+.+.}, at: [<ffffffff81587c4a>] cgroup_attach_task_all+0x2a/0x140 kernel/cgroup/cgroup-v1.c:57
1 lock held by syz-executor.3/2301:
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] copy_process kernel/fork.c:1595 [inline]
 #0:  (&cgroup_threadgroup_rwsem){++++}, at: [<ffffffff8137691e>] _do_fork+0x19e/0xce0 kernel/fork.c:2085

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

NMI backtrace for cpu 1
CPU: 1 PID: 1017 Comm: khungtaskd Not tainted 4.14.154 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x142/0x197 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x94 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x141/0x189 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:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5e7/0xb90 kernel/hung_task.c:274
 kthread+0x319/0x430 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 2294 Comm: syz-executor.5 Not tainted 4.14.154 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88809be04340 task.stack: ffff888083d48000
RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:60
RSP: 0018:ffff888083d4f2e0 EFLAGS: 00000206
RAX: 0000000000000003 RBX: ffff88807f580e00 RCX: 0000000000000004
RDX: 0000000000000000 RSI: ffffffff81153040 RDI: ffff88807f581188
RBP: ffff888083d4f310 R08: 1ffffffff0ea6416 R09: ffff888083d4f518
R10: ffffed100feb0911 R11: ffff88807f58488e R12: 0000000000000001
R13: 0000000000000010 R14: 00000000fff9ffef R15: 000000000000ffff
FS:  00007fc30b9c6700(0000) GS:ffff8880aee00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000009b7bc000 CR4: 00000000001426f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 vmx_get_segment arch/x86/kvm/vmx.c:4712 [inline]
 vmx_get_segment+0x3d4/0x7e0 arch/x86/kvm/vmx.c:4695
 kvm_get_segment arch/x86/kvm/x86.c:4573 [inline]
 emulator_get_segment+0xbd/0x480 arch/x86/kvm/x86.c:5343
 __linearize arch/x86/kvm/emulate.c:712 [inline]
 linearize+0x1db/0x7f0 arch/x86/kvm/emulate.c:757
 segmented_read_std+0x83/0x120 arch/x86/kvm/emulate.c:835
 em_fxrstor.part.0+0x156/0x460 arch/x86/kvm/emulate.c:4059
 em_fxrstor+0x2c/0x40 arch/x86/kvm/emulate.c:4055
 x86_emulate_insn+0x560/0x4120 arch/x86/kvm/emulate.c:5537
 x86_emulate_instruction+0x3ff/0x1710 arch/x86/kvm/x86.c:5977
 kvm_mmu_page_fault+0x1c5/0x300 arch/x86/kvm/mmu.c:5089
 handle_ept_violation+0x157/0x440 arch/x86/kvm/vmx.c:6918
 vmx_handle_exit+0x20d/0x1330 arch/x86/kvm/vmx.c:9191
 vcpu_enter_guest+0xf28/0x5220 arch/x86/kvm/x86.c:7300
 vcpu_run arch/x86/kvm/x86.c:7363 [inline]
 kvm_arch_vcpu_ioctl_run+0x318/0x1000 arch/x86/kvm/x86.c:7530
 kvm_vcpu_ioctl+0x401/0xd10 arch/x86/kvm/../../../virt/kvm/kvm_main.c:2641
 vfs_ioctl fs/ioctl.c:46 [inline]
 file_ioctl fs/ioctl.c:500 [inline]
 do_vfs_ioctl+0x7ae/0x1060 fs/ioctl.c:684
 SYSC_ioctl fs/ioctl.c:701 [inline]
 SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45a639
RSP: 002b:00007fc30b9c5c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a639
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000008
RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc30b9c66d4
R13: 00000000004c3cdd R14: 00000000004d7fb0 R15: 00000000ffffffff
Code: 00 00 48 c7 c7 60 91 6e 86 4c 89 35 cb 49 be 07 41 be f4 ff ff ff e8 a3 3b ee ff 48 c7 05 b5 49 be 07 00 00 00 00 e9 2f ec ff ff <65> 48 8b 04 25 40 ee 01 00 48 85 c0 74 1a 65 8b 15 eb b3 a4 7e 

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/11/17 09:12 linux-4.14.y 775d01b65b5d d5696d51 .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.