bisecting fixing commit since 97a8651cadce7c2b7c4d8f108b392eff31fe2c08 building syzkaller on 77e2b66864e69c17416614228723a1ebd3581ddc testing commit 97a8651cadce7c2b7c4d8f108b392eff31fe2c08 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ae1f80349573b595bacd7aa9aada24a9bf41e4c6225ab6a3ff588932ec1ee882 run #0: crashed: INFO: task hung in paste_selection run #1: crashed: INFO: task hung in paste_selection run #2: crashed: INFO: task hung in paste_selection run #3: crashed: INFO: task hung in paste_selection run #4: crashed: INFO: task hung in paste_selection run #5: crashed: INFO: task hung in paste_selection run #6: crashed: INFO: task hung in paste_selection run #7: crashed: INFO: task hung in paste_selection run #8: crashed: INFO: task hung in paste_selection run #9: crashed: INFO: task hung in paste_selection run #10: crashed: INFO: task hung in paste_selection run #11: crashed: INFO: task hung in tty_ldisc_hangup run #12: crashed: INFO: task hung in paste_selection run #13: crashed: INFO: task hung in paste_selection run #14: crashed: INFO: task hung in paste_selection run #15: crashed: INFO: task hung in paste_selection run #16: crashed: INFO: task hung in paste_selection run #17: crashed: INFO: task hung in paste_selection run #18: crashed: INFO: task hung in paste_selection run #19: crashed: INFO: task hung in paste_selection testing current HEAD e23d55af0e1fca9be5c99f0c37d48b289f4d6489 testing commit e23d55af0e1fca9be5c99f0c37d48b289f4d6489 compiler: gcc version 8.4.1 20210217 (GCC) kernel signature: ac9e6bd669045282312a290949e694d8d56028cf2b047b1d82b780befd0b3acf all runs: crashed: INFO: task hung in paste_selection revisions tested: 2, total time: 32m56.525085064s (build: 18m45.416606072s, test: 13m40.200623678s) the crash still happens on HEAD commit msg: Linux 4.19.205 crash: INFO: task hung in paste_selection Bluetooth: hci0: command 0x0406 tx timeout Bluetooth: hci2: command 0x0406 tx timeout Bluetooth: hci1: command 0x0406 tx timeout ieee802154 phy0 wpan0: encryption failed: -22 ieee802154 phy1 wpan1: encryption failed: -22 INFO: task syz-executor.0:12977 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D28744 12977 8490 0x00000004 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007febe9edd188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe69e6f1ff R14: 00007febe9edd300 R15: 0000000000022000 INFO: task syz-executor.5:12991 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28664 12991 8489 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007efc17c74188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffc27d1691f R14: 00007efc17c74300 R15: 0000000000022000 INFO: task syz-executor.1:12993 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28744 12993 8487 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007f4294fde188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056c008 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056c008 R13: 00007ffc95a067df R14: 00007f4294fde300 R15: 0000000000022000 INFO: task syz-executor.2:13002 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28744 13002 8481 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007f2663a3f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff2aa31dff R14: 00007f2663a3f300 R15: 0000000000022000 INFO: task syz-executor.3:13004 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28744 13004 8483 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007fb007122188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe59a7b2df R14: 00007fb007122300 R15: 0000000000022000 INFO: task syz-executor.4:13012 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28856 13012 8486 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007fe325efe188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffce7b5c95f R14: 00007fe325efe300 R15: 0000000000022000 INFO: task syz-executor.5:13023 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28856 13023 8489 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007efc17c95188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc27d1691f R14: 00007efc17c95300 R15: 0000000000022000 INFO: task syz-executor.1:13026 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28856 13026 8487 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007f4294fff188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffc95a067df R14: 00007f4294fff300 R15: 0000000000022000 INFO: task syz-executor.2:13038 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28760 13038 8481 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007f2663a3f188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007fff2aa31dff R14: 00007f2663a3f300 R15: 0000000000022000 INFO: task syz-executor.3:13042 blocked for more than 140 seconds. Not tainted 4.19.205-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28856 13042 8483 0x00000000 Call Trace: context_switch kernel/sched/core.c:2828 [inline] __schedule+0x80c/0x1f70 kernel/sched/core.c:3517 schedule+0x7f/0x1b0 kernel/sched/core.c:3561 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:3619 __mutex_lock_common kernel/locking/mutex.c:1015 [inline] __mutex_lock+0x4ba/0x1190 kernel/locking/mutex.c:1083 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1098 tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 paste_selection+0x114/0x430 drivers/tty/vt/selection.c:372 tioclinux+0xfb/0x390 drivers/tty/vt/vt.c:3055 vt_ioctl+0x19f8/0x2200 drivers/tty/vt/vt_ioctl.c:372 tty_ioctl+0x456/0x1290 drivers/tty/tty_io.c:2669 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0x196/0x10c0 fs/ioctl.c:688 ksys_ioctl+0x62/0x90 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6e/0xb0 fs/ioctl.c:710 do_syscall_64+0xd0/0x4e0 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4665f9 Code: Bad RIP value. RSP: 002b:00007fb007122188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000056bf60 RCX: 00000000004665f9 RDX: 00000000200000c0 RSI: 000000000000541c RDI: 0000000000000003 RBP: 00000000004bfce1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf60 R13: 00007ffe59a7b2df R14: 00007fb007122300 R15: 0000000000022000 Showing all locks held in the system: 1 lock held by khungtaskd/1570: #0: 00000000dbf0ac43 (rcu_read_lock){....}, at: debug_show_all_locks+0x5b/0x27a kernel/locking/lockdep.c:4443 1 lock held by in:imklog/7807: #0: 000000004369f45f (&f->f_pos_lock){+.+.}, at: __fdget_pos+0xa7/0xd0 fs/file.c:767 2 locks held by login/12237: #0: 00000000a7a11e2c (&tty->legacy_mutex){+.+.}, at: tty_lock+0x4d/0x70 drivers/tty/tty_mutex.c:19 #1: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_write+0x2d/0x40 drivers/tty/tty_ldsem.c:388 2 locks held by syz-executor.4/12973: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.0/12977: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.5/12991: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.1/12993: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.2/13002: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.3/13004: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.4/13012: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.5/13023: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.1/13026: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.2/13038: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.3/13042: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.4/13052: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 2 locks held by syz-executor.5/13059: #0: 00000000002817b7 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x2d/0x40 drivers/tty/tty_ldsem.c:362 #1: 000000004253c364 (&buf->lock){+.+.}, at: tty_buffer_lock_exclusive+0x2b/0x30 drivers/tty/tty_buffer.c:61 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1570 Comm: khungtaskd Not tainted 4.19.205-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+0x17c/0x226 lib/dump_stack.c:118 nmi_cpu_backtrace.cold.0+0x3c/0x78 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0xf6/0x120 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:203 [inline] watchdog+0x5c3/0xb40 kernel/hung_task.c:287 kthread+0x347/0x410 kernel/kthread.c:259 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt+0x12/0x20 arch/x86/include/asm/irqflags.h:60