Hello,

syzbot found the following crash on:

HEAD commit: a99d8080 Linux 5.4-rc6 git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=10afae68e00000 kernel config: https://syzkaller.appspot.com/x/.config?x=8c5e2eca3f31f9bf dashboard link: https://syzkaller.appspot.com/bug?extid=f1048ebddb93befb085f compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=126bc658e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+f1048ebddb93befb085f@syzkaller.appspotmail.com

INFO: task syz-executor.0:12251 blocked for more than 143 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28160 12251 8868 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_close+0x7e/0x100 sound/core/timer.c:422 snd_timer_user_release+0x98/0x130 sound/core/timer.c:1478 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413db1 Code: c0 c3 0f 1f 80 00 00 00 00 c7 07 00 00 00 00 31 c0 c3 0f 1f 80 00 00 00 00 31 c0 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 b8 <2d> f8 ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 31 c0 c3 66 66 66 66 RSP: 002b:00007ffdda4a34b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413db1 RDX: 0000001b2dd20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffdda4a3590 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760a90 R15: 000000000075bf2c INFO: task syz-executor.2:12256 blocked for more than 143 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28160 12256 8864 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_close+0x7e/0x100 sound/core/timer.c:422 snd_timer_user_release+0x98/0x130 sound/core/timer.c:1478 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413db1 Code: c0 c3 0f 1f 80 00 00 00 00 c7 07 00 00 00 00 31 c0 c3 0f 1f 80 00 00 00 00 31 c0 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 b8 <2d> f8 ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 31 c0 c3 66 66 66 66 RSP: 002b:00007ffe078ed7d0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413db1 RDX: 0000001b2da20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffe078ed8b0 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760a90 R15: 000000000075bf2c INFO: task syz-executor.4:12266 blocked for more than 144 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28480 12266 8871 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_open+0x98/0x1860 sound/core/timer.c:245 snd_timer_user_tselect sound/core/timer.c:1728 [inline] __snd_timer_user_ioctl.isra.0+0x68b/0x1fd0 sound/core/timer.c:2003 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2033 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/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+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007f2806975c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a219 RDX: 0000000020029fcc RSI: 0000000040345410 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28069766d4 R13: 00000000004cf428 R14: 00000000004d9760 R15: 00000000ffffffff INFO: task syz-executor.4:12269 blocked for more than 144 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29712 12269 8871 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/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+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007f2806954c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 000000000045a219 RDX: 0000000000000000 RSI: 00000000000054a0 RDI: 0000000000000003 RBP: 000000000075bfc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28069556d4 R13: 00000000004c4ae8 R14: 00000000004d9778 R15: 00000000ffffffff INFO: task syz-executor.4:12271 blocked for more than 144 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28000 12271 8871 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_open+0x98/0x1860 sound/core/timer.c:245 snd_seq_timer_open+0x240/0x590 sound/core/seq/seq_timer.c:275 queue_use+0xf1/0x270 sound/core/seq/seq_queue.c:489 snd_seq_queue_alloc+0x2c5/0x4d0 sound/core/seq/seq_queue.c:176 snd_seq_ioctl_create_queue+0xb0/0x330 sound/core/seq/seq_clientmgr.c:1548 snd_seq_kernel_client_ctl+0xf8/0x140 sound/core/seq/seq_clientmgr.c:2353 alloc_seq_queue.isra.0+0xdc/0x180 sound/core/seq/oss/seq_oss_init.c:357 snd_seq_oss_open+0x2ff/0x960 sound/core/seq/oss/seq_oss_init.c:215 odev_open+0x70/0x90 sound/core/seq/oss/seq_oss.c:125 soundcore_open+0x453/0x610 sound/sound_core.c:593 chrdev_open+0x245/0x6b0 fs/char_dev.c:414 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3408 [inline] path_openat+0x10e9/0x46d0 fs/namei.c:3525 do_filp_open+0x1a1/0x280 fs/namei.c:3555 do_sys_open+0x3fe/0x5d0 fs/open.c:1097 __do_sys_openat fs/open.c:1124 [inline] __se_sys_openat fs/open.c:1118 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1118 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007f2806933c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a219 RDX: 0000000000000001 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28069346d4 R13: 00000000004c734a R14: 00000000004dcf88 R15: 00000000ffffffff INFO: task syz-executor.4:12273 blocked for more than 145 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28552 12273 8871 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/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+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007f2806912c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 000000000045a219 RDX: 0000000000000000 RSI: 00000000000054a0 RDI: 0000000000000003 RBP: 000000000075c118 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28069136d4 R13: 00000000004c4ae8 R14: 00000000004d9778 R15: 00000000ffffffff INFO: task syz-executor.4:12275 blocked for more than 145 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29312 12275 8871 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_open+0x98/0x1860 sound/core/timer.c:245 snd_timer_user_tselect sound/core/timer.c:1728 [inline] __snd_timer_user_ioctl.isra.0+0x68b/0x1fd0 sound/core/timer.c:2003 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2033 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/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+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007f28068f1c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a219 RDX: 0000000020029fcc RSI: 0000000040345410 RDI: 0000000000000003 RBP: 000000000075c1c0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28068f26d4 R13: 00000000004cf428 R14: 00000000004d9760 R15: 00000000ffffffff INFO: task syz-executor.4:12276 blocked for more than 146 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28536 12276 8871 0x00004004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 odev_open+0x5f/0x90 sound/core/seq/oss/seq_oss.c:124 soundcore_open+0x453/0x610 sound/sound_core.c:593 chrdev_open+0x245/0x6b0 fs/char_dev.c:414 do_dentry_open+0x4e6/0x1380 fs/open.c:797 vfs_open+0xa0/0xd0 fs/open.c:914 do_last fs/namei.c:3408 [inline] path_openat+0x10e9/0x46d0 fs/namei.c:3525 do_filp_open+0x1a1/0x280 fs/namei.c:3555 do_sys_open+0x3fe/0x5d0 fs/open.c:1097 __do_sys_openat fs/open.c:1124 [inline] __se_sys_openat fs/open.c:1118 [inline] __x64_sys_openat+0x9d/0x100 fs/open.c:1118 do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007f28068d0c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 000000000045a219 RDX: 0000000000000001 RSI: 0000000020000000 RDI: ffffffffffffff9c RBP: 000000000075c268 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f28068d16d4 R13: 00000000004c734a R14: 00000000004dcf88 R15: 00000000ffffffff INFO: task syz-executor.1:12261 blocked for more than 146 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28160 12261 8866 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_close+0x7e/0x100 sound/core/timer.c:422 snd_timer_user_release+0x98/0x130 sound/core/timer.c:1478 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413db1 Code: c0 c3 0f 1f 80 00 00 00 00 c7 07 00 00 00 00 31 c0 c3 0f 1f 80 00 00 00 00 31 c0 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 b8 <2d> f8 ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 31 c0 c3 66 66 66 66 RSP: 002b:00007ffe3503b380 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413db1 RDX: 0000001b2db20000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 0000000000000001 R08: ffffffffffffffff R09: ffffffffffffffff R10: 00007ffe3503b460 R11: 0000000000000293 R12: 000000000075c9a0 R13: 000000000075c9a0 R14: 0000000000760a90 R15: 000000000075bf2c INFO: task syz-executor.5:12267 blocked for more than 147 seconds. Not tainted 5.4.0-rc6 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28552 12267 8870 0x00000004 Call Trace: context_switch kernel/sched/core.c:3384 [inline] __schedule+0x94f/0x1e70 kernel/sched/core.c:4069 schedule+0xd9/0x260 kernel/sched/core.c:4136 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4195 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 snd_timer_open+0x98/0x1860 sound/core/timer.c:245 snd_timer_user_tselect sound/core/timer.c:1728 [inline] __snd_timer_user_ioctl.isra.0+0x68b/0x1fd0 sound/core/timer.c:2003 snd_timer_user_ioctl+0x7a/0xa7 sound/core/timer.c:2033 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:509 [inline] do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 ksys_ioctl+0xab/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+0xfa/0x760 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45a219 Code: Bad RIP value. RSP: 002b:00007ff76c742c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 000000000045a219 RDX: 0000000020029fcc RSI: 0000000040345410 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff76c7436d4 R13: 00000000004cf428 R14: 00000000004d9760 R15: 00000000ffffffff

Showing all locks held in the system: 1 lock held by khungtaskd/1070: #0: ffffffff88fab340 (rcu_read_lock){....}, at: debug_show_all_locks+0x5f/0x27e kernel/locking/lockdep.c:5337 1 lock held by rsyslogd/8724: #0: ffff88809ae4bd60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xee/0x110 fs/file.c:801 2 locks held by getty/8813: #0: ffff8880a459b090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f152e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8814: #0: ffff8880a9021090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f212e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8815: #0: ffff8880a818a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f192e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8816: #0: ffff8880a843a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f1d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8817: #0: ffff8880a2834090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f252e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8818: #0: ffff88809aafe090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005f292e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by getty/8819: #0: ffff8880a514a090 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x33/0x40 drivers/tty/tty_ldsem.c:340 #1: ffffc90005ef12e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x232/0x1c10 drivers/tty/n_tty.c:2156 2 locks held by syz-executor.3/12245: 2 locks held by syz-executor.0/12251: #0: ffff888082e84550 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_release+0x67/0x130 sound/core/timer.c:1476 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_close+0x7e/0x100 sound/core/timer.c:422 2 locks held by syz-executor.2/12256: #0: ffff88809c005150 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_release+0x67/0x130 sound/core/timer.c:1476 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_close+0x7e/0x100 sound/core/timer.c:422 2 locks held by syz-executor.4/12266: #0: ffff8880a9b93950 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_open+0x98/0x1860 sound/core/timer.c:245 1 lock held by syz-executor.4/12269: #0: ffff8880a9b93950 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 2 locks held by syz-executor.4/12271: #0: ffffffff89924320 (register_mutex#4){+.+.}, at: odev_open+0x5f/0x90 sound/core/seq/oss/seq_oss.c:124 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_open+0x98/0x1860 sound/core/timer.c:245 1 lock held by syz-executor.4/12273: #0: ffff888096c8d550 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 2 locks held by syz-executor.4/12275: #0: ffff888096c8d550 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_open+0x98/0x1860 sound/core/timer.c:245 1 lock held by syz-executor.4/12276: #0: ffffffff89924320 (register_mutex#4){+.+.}, at: odev_open+0x5f/0x90 sound/core/seq/oss/seq_oss.c:124 2 locks held by syz-executor.1/12261: #0: ffff88809a826950 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_release+0x67/0x130 sound/core/timer.c:1476 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_close+0x7e/0x100 sound/core/timer.c:422 2 locks held by syz-executor.5/12267: #0: ffff8880970f0950 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_open+0x98/0x1860 sound/core/timer.c:245 1 lock held by syz-executor.5/12270: #0: ffff8880970f0950 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 1 lock held by syz-executor.5/12272: #0: ffffffff89924320 (register_mutex#4){+.+.}, at: odev_open+0x5f/0x90 sound/core/seq/oss/seq_oss.c:124 1 lock held by syz-executor.5/12274: #0: ffff8880a0113d50 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 2 locks held by syz-executor.5/12277: #0: ffff8880a0113d50 (&tu->ioctl_lock){+.+.}, at: snd_timer_user_ioctl+0x51/0xa7 sound/core/timer.c:2032 #1: ffffffff89914b00 (register_mutex){+.+.}, at: snd_timer_open+0x98/0x1860 sound/core/timer.c:245 1 lock held by syz-executor.5/12279: #0: ffffffff89924320 (register_mutex#4){+.+.}, at: odev_open+0x5f/0x90 sound/core/seq/oss/seq_oss.c:124

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

NMI backtrace for cpu 1 CPU: 1 PID: 1070 Comm: khungtaskd Not tainted 5.4.0-rc6 #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+0x172/0x1f0 lib/dump_stack.c:113 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+0x9d0/0xef0 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 12245 Comm: syz-executor.3 Not tainted 5.4.0-rc6 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rdtsc_ordered arch/x86/include/asm/msr.h:236 [inline] RIP: 0010:delay_tsc+0x4a/0xc0 arch/x86/lib/delay.c:61 Code: 0f 01 f9 66 90 48 c1 e2 20 48 09 c2 49 89 d4 eb 16 f3 90 bf 01 00 00 00 e8 03 c2 01 fa e8 de cd f9 fb 44 39 e8 75 36 0f 01 f9 <66> 90 48 c1 e2 20 48 89 d3 48 09 c3 48 89 d8 4c 29 e0 4c 39 f0 73 RSP: 0018:ffff88808034fc70 EFLAGS: 00000246 RAX: 000000004e0d2263 RBX: 000002d24e0d2178 RCX: 0000000000000000 RDX: 00000000000002d2 RSI: ffffffff8347345c RDI: 0000000000000005 RBP: ffff88808034fc90 R08: ffff8880998302c0 R09: fffffbfff14efd42 R10: fffffbfff14efd41 R11: ffffffff8a77ea0f R12: 000002d24e0d173d R13: 0000000000000000 R14: 00000000000059d9 R15: ffff88809ccb0108 FS: 0000000000fa4940(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffff600400 CR3: 0000000095a99000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __delay arch/x86/lib/delay.c:161 [inline] __const_udelay+0x59/0x80 arch/x86/lib/delay.c:175 snd_timer_close_locked+0x22a/0xda0 sound/core/timer.c:369 snd_timer_close+0x8a/0x100 sound/core/timer.c:423 snd_timer_user_release+0x98/0x130 sound/core/timer.c:1478 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline] syscall_return_slowpath arch/x86/entry/common.c:274 [inline] do_syscall_64+0x65f/0x760 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x413db1 Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 04 1b 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01 RSP: 002b:00007fff58da8ec0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000413db1 RDX: 0000000000000000 RSI: 0000000000000081 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000760a88 R09: ffffffffffffffff R10: 00007fff58da8f90 R11: 0000000000000293 R12: 000000000075bf20 R13: 0000000000000003 R14: 0000000000760a90 R15: 000000000075bf2c

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