NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 NOHZ: local_softirq_pending 08 INFO: task syz-executor.5:7848 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D28032 7848 6866 0x00000006 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072 fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1486 __fput+0x2ce/0x890 fs/file_table.c:278 task_work_run+0x148/0x1c0 kernel/task_work.c:113 get_signal+0x1b64/0x1f70 kernel/signal.c:2399 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:821 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline] syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fc922260c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: 0000000000000000 RBX: 000000000000ce80 RCX: 000000000045c1d9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000007 RBP: 000000000078bfe0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac R13: 00007ffec7ba0caf R14: 00007fc9222619c0 R15: 000000000078bfac INFO: task syz-executor.5:7889 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29496 7889 6866 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x90e/0xef0 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x183/0x2a0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 do_fb_ioctl+0x33e/0xb50 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fc9221dcc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000ce80 RCX: 000000000045c1d9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000006 RBP: 000000000078c260 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c22c R13: 00007ffec7ba0caf R14: 00007fc9221dd9c0 R15: 000000000078c22c INFO: task syz-executor.5:7890 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D29496 7890 6866 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x90e/0xef0 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x183/0x2a0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 do_fb_ioctl+0x33e/0xb50 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fc9221bbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000ce80 RCX: 000000000045c1d9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000007 RBP: 000000000078c300 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c2cc R13: 00007ffec7ba0caf R14: 00007fc9221bc9c0 R15: 000000000078c2cc INFO: task syz-executor.4:7886 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D29496 7886 6851 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x90e/0xef0 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x183/0x2a0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 do_fb_ioctl+0x33e/0xb50 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fe440e40c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000ce80 RCX: 000000000045c1d9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000006 RBP: 000000000078bfe0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac R13: 00007ffe0bb5136f R14: 00007fe440e419c0 R15: 000000000078bfac INFO: task syz-executor.4:7888 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28952 7888 6851 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_timeout+0x90e/0xef0 kernel/time/timer.c:1782 __down_common kernel/locking/semaphore.c:221 [inline] __down+0x183/0x2a0 kernel/locking/semaphore.c:238 down+0x57/0x80 kernel/locking/semaphore.c:62 console_lock+0x25/0x80 kernel/printk/printk.c:2244 do_fb_ioctl+0x33e/0xb50 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fe440dfec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000ce80 RCX: 000000000045c1d9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000006 RBP: 000000000078c120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c0ec R13: 00007ffe0bb5136f R14: 00007fe440dff9c0 R15: 000000000078c0ec INFO: task syz-executor.3:7913 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D29520 7913 6762 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072 fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 chrdev_open+0x266/0x770 fs/char_dev.c:423 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007f79b54eec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000020880 RCX: 000000000045c1d9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007fff91f63baf R14: 00007f79b54ef9c0 R15: 000000000078bf0c INFO: task syz-executor.3:7916 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.3 D28152 7916 6762 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072 fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 chrdev_open+0x266/0x770 fs/char_dev.c:423 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007f79b54cdc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000020880 RCX: 000000000045c1d9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078bfe8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac R13: 00007fff91f63baf R14: 00007f79b54ce9c0 R15: 000000000078bfac INFO: task syz-executor.0:7919 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29464 7919 6464 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072 fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 chrdev_open+0x266/0x770 fs/char_dev.c:423 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fbee6d92c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000020880 RCX: 000000000045c1d9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007fffca122b9f R14: 00007fbee6d939c0 R15: 000000000078bf0c INFO: task syz-executor.0:7933 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.0 D29520 7933 6464 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072 fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 chrdev_open+0x266/0x770 fs/char_dev.c:423 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fbee6d50c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000020880 RCX: 000000000045c1d9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078c088 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c04c R13: 00007fffca122b9f R14: 00007fbee6d519c0 R15: 000000000078c04c INFO: task syz-executor.1:7924 blocked for more than 140 seconds. Not tainted 4.19.133-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28256 7924 6582 0x00000004 Call Trace: context_switch kernel/sched/core.c:2826 [inline] __schedule+0x887/0x2040 kernel/sched/core.c:3515 schedule+0x8d/0x1b0 kernel/sched/core.c:3559 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3617 __mutex_lock_common kernel/locking/mutex.c:1002 [inline] __mutex_lock+0x647/0x1260 kernel/locking/mutex.c:1072 fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 chrdev_open+0x266/0x770 fs/char_dev.c:423 do_dentry_open+0x4aa/0x1160 fs/open.c:796 do_last fs/namei.c:3421 [inline] path_openat+0x793/0x2df0 fs/namei.c:3537 do_filp_open+0x18c/0x3f0 fs/namei.c:3567 do_sys_open+0x3b3/0x520 fs/open.c:1085 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 18 0f 57 c0 0f 11 44 24 20 48 c7 44 24 30 64 00 00 00 0f 11 44 24 38 48 89 5c 24 48 e8 c0 dc ff ff 48 8b 44 24 50 48 85 c0 75 <12> 48 8b 8c 24 c8 01 00 00 0f ba e1 00 0f 83 13 01 00 00 48 83 f8 RSP: 002b:00007fe984891c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000020880 RCX: 000000000045c1d9 RDX: 0000000000000000 RSI: 0000000020000180 RDI: ffffffffffffff9c RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c R13: 00007ffee904a0bf R14: 00007fe9848929c0 R15: 000000000078bf0c Showing all locks held in the system: 1 lock held by khungtaskd/1075: #0: 00000000aa95fb92 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4440 1 lock held by in:imklog/6141: #0: 00000000c636e3d0 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767 1 lock held by syz-executor.5/7848: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1486 3 locks held by syz-executor.2/7874: 1 lock held by syz-executor.3/7913: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 1 lock held by syz-executor.3/7916: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 1 lock held by syz-executor.0/7919: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 1 lock held by syz-executor.0/7933: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 1 lock held by syz-executor.1/7924: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 1 lock held by syz-executor.1/7928: #0: 0000000058b60574 (&fb_info->lock){+.+.}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1457 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1075 Comm: khungtaskd Not tainted 4.19.133-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+0x1fc/0x2fe lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1a6/0x1eb lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline] watchdog+0x991/0xe60 kernel/hung_task.c:287 kthread+0x30b/0x410 kernel/kthread.c:246 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 CPU: 0 PID: 7874 Comm: syz-executor.2 Not tainted 4.19.133-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__read_once_size include/linux/compiler.h:193 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:69 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x1c/0x50 kernel/kcov.c:101 Code: 76 f4 26 0a 00 00 00 00 e9 39 ec ff ff 90 48 8b 34 24 65 48 8b 04 25 40 ee 01 00 65 8b 15 ec 44 98 7e 81 e2 00 01 1f 00 75 2b <8b> 90 d8 12 00 00 83 fa 02 75 20 48 8b 88 e0 12 00 00 8b 80 dc 12 RSP: 0018:ffff88804d2d72b8 EFLAGS: 00000246 RAX: ffff88804b38c0c0 RBX: 0000000000000050 RCX: ffffffff8385d7e4 RDX: 0000000000000000 RSI: ffffffff8385d7d0 RDI: 0000000000000004 RBP: 0000000000000040 R08: 0000000000000001 R09: 0000000000000050 R10: 0000000000000004 R11: 0000000000000000 R12: ffff8880000a0040 R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000f0543124 FS: 00007f8141154700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3d62dac000 CR3: 000000009b371000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: writeb arch/x86/include/asm/io.h:65 [inline] vga16fb_fillrect+0x9c0/0x1940 drivers/video/fbdev/vga16fb.c:923 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 fbcon_clear_margins+0x1e2/0x350 drivers/video/fbdev/core/fbcon.c:1342 fbcon_switch+0x1038/0x1d26 drivers/video/fbdev/core/fbcon.c:2324 redraw_screen+0x37d/0x870 drivers/tty/vt/vt.c:1015 fbcon_modechanged+0x6e9/0x9f0 drivers/video/fbdev/core/fbcon.c:2972 fbcon_event_notify+0x197/0x1d80 drivers/video/fbdev/core/fbcon.c:3347 notifier_call_chain+0xc0/0x230 kernel/notifier.c:93 __blocking_notifier_call_chain kernel/notifier.c:317 [inline] __blocking_notifier_call_chain kernel/notifier.c:304 [inline] blocking_notifier_call_chain kernel/notifier.c:328 [inline] blocking_notifier_call_chain+0x85/0xa0 kernel/notifier.c:325 fb_set_var+0xc51/0xe20 drivers/video/fbdev/core/fbmem.c:1042 do_fb_ioctl+0x3cf/0xb50 drivers/video/fbdev/core/fbmem.c:1115 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1230 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:501 [inline] do_vfs_ioctl+0xcdb/0x12e0 fs/ioctl.c:688 ksys_ioctl+0x9b/0xc0 fs/ioctl.c:705 __do_sys_ioctl fs/ioctl.c:712 [inline] __se_sys_ioctl fs/ioctl.c:710 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:710 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c1d9 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f8141153c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000ce80 RCX: 000000000045c1d9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 000000000000000a RBP: 000000000078c120 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078c0ec R13: 00007ffff49bc72f R14: 00007f81411549c0 R15: 000000000078c0ec