INFO: task syz-executor.5:15593 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28360 15593 10978 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: Bad RIP value. RSP: 002b:00007fc180a29c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc180a2a6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bf2c INFO: task syz-executor.1:15607 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28360 15607 10974 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007f80452adc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f80452ae6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bf2c INFO: task syz-executor.1:15613 blocked for more than 143 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28360 15613 10974 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007f804528cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f804528d6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040186f40 RDI: 0000000000000004 RBP: 000000000076bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bfcc INFO: task syz-executor.1:15623 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28360 15623 10974 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007f804526bc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f804526c6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076c060 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076c06c INFO: task syz-executor.2:15603 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28360 15603 10970 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007f4ac5adec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4ac5adf6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bf2c INFO: task syz-executor.2:15610 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28360 15610 10970 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007f4ac5abdc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4ac5abe6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040186f40 RDI: 0000000000000004 RBP: 000000000076bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bfcc INFO: task syz-executor.2:15621 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28360 15621 10970 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007f4ac5a9cc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f4ac5a9d6d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076c060 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076c06c INFO: task syz-executor.0:15600 blocked for more than 144 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28360 15600 10976 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_timeout+0x717/0xc50 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x29c/0x440 kernel/sched/completion.c:136 kthread_stop+0x187/0x800 kernel/kthread.c:559 ubi_detach_mtd_dev+0x219/0x43a drivers/mtd/ubi/build.c:1101 ctrl_cdev_ioctl+0x1d6/0x2d0 drivers/mtd/ubi/cdev.c:1068 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007fde4ac43c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fde4ac446d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bf2c INFO: task syz-executor.0:15608 blocked for more than 145 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28360 15608 10976 0x00004004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007fde4ac22c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fde4ac236d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040186f40 RDI: 0000000000000004 RBP: 000000000076bfc0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076bfcc INFO: task syz-executor.0:15618 blocked for more than 145 seconds. Not tainted 5.6.0-rc3-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28360 15618 10976 0x00000004 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x934/0x1f90 kernel/sched/core.c:4080 schedule+0xdc/0x2b0 kernel/sched/core.c:4154 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4213 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: 48 8b 5c 24 30 48 01 d8 48 89 04 24 48 89 4c 24 08 e8 db 67 fa ff 48 8b 4c 24 10 48 8b 44 24 18 48 ff c0 48 83 f8 06 7c ce 48 <89> 4c 24 40 48 8b 6c 24 20 48 83 c4 28 c3 e8 84 b4 ff ff eb 92 cc RSP: 002b:00007fde4ac01c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fde4ac026d4 RCX: 000000000045c449 RDX: 000000000076006e RSI: 0000000040046f41 RDI: 0000000000000003 RBP: 000000000076c060 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000207 R14: 00000000004c3e89 R15: 000000000076c06c Showing all locks held in the system: 3 locks held by kworker/u4:7/568: #0: ffff8880ae937558 (&rq->lock){-.-.}, at: rq_lock kernel/sched/sched.h:1215 [inline] #0: ffff8880ae937558 (&rq->lock){-.-.}, at: __schedule+0x232/0x1f90 kernel/sched/core.c:4028 #1: ffffffff89bac280 (rcu_read_lock){....}, at: __update_idle_core+0x45/0x3f0 kernel/sched/fair.c:5747 #2: ffff8880ae927418 (&base->lock){-.-.}, at: lock_timer_base+0x56/0x1b0 kernel/time/timer.c:936 1 lock held by khungtaskd/1120: #0: ffffffff89bac280 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x279 kernel/locking/lockdep.c:5333 1 lock held by rsyslogd/10796: #0: ffff88809f04e8e0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:821 2 locks held by getty/10918: #0: ffff88809e861090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017fb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10919: #0: ffff888095911090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000188b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10920: #0: ffff888086e96090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000187b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10921: #0: ffff8880a709e090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000186b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10922: #0: ffff88809d751090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000182b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10923: #0: ffff888091692090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc9000185b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 2 locks held by getty/10924: #0: ffff8880a698b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc900017cb2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x220/0x1bf0 drivers/tty/n_tty.c:2156 1 lock held by syz-executor.5/15593: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.1/15607: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.1/15613: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 1 lock held by syz-executor.1/15623: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.2/15603: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.2/15610: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 1 lock held by syz-executor.2/15621: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.0/15600: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.0/15608: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 1 lock held by syz-executor.0/15618: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.4/15601: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.4/15609: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 1 lock held by syz-executor.4/15617: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.3/15611: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 1 lock held by syz-executor.3/15614: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x22b/0x2d0 drivers/mtd/ubi/cdev.c:1042 1 lock held by syz-executor.3/15625: #0: ffffffff8a330800 (ubi_devices_mutex){+.+.}, at: ctrl_cdev_ioctl+0x1cd/0x2d0 drivers/mtd/ubi/cdev.c:1067 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 1120 Comm: khungtaskd Not tainted 5.6.0-rc3-syzkaller #0 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+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b 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+0xb11/0x10c0 kernel/hung_task.c:289 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 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+0xe/0x10 arch/x86/include/asm/irqflags.h:60