INFO: task syz-executor.1:16805 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.1 D28104 16805 7189 0x00000004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1447 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x463/0x620 kernel/locking/lockdep.c:3702 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x9b/0xe0 kernel/locking/spinlock.c:191 fsnotify+0x7df/0xb50 include/linux/srcu.h:181 fsnotify_parent+0xbf/0x2d0 fs/notify/fsnotify.c:153 spin_unlock include/linux/spinlock.h:393 [inline] locks_remove_file+0x329/0x590 fs/locks.c:2794 task_work_run+0xd3/0x1b0 kernel/task_work.c:119 fcntl_setlk+0xcc0/0xcc0 fs/locks.c:2542 unregister_framebuffer+0x30/0x30 drivers/video/fbdev/core/fbmem.c:1860 lock_fb_info include/linux/fb.h:637 [inline] fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1447 lock_fb_info include/linux/fb.h:637 [inline] fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1447 __fput+0x33e/0x880 fs/file_table.c:280 task_work_run+0xf4/0x1b0 kernel/task_work.c:123 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline] syscall_return_slowpath arch/x86/entry/common.c:279 [inline] do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.4:16817 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D27064 16817 7512 0x00004004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 rwlock_bug.part.0+0x90/0x90 include/linux/sched.h:1329 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 set_irq_regs arch/x86/include/asm/irq_regs.h:27 [inline] smp_apic_timer_interrupt+0x1b6/0x600 arch/x86/kernel/apic/apic.c:1142 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 get_fb_info.part.0+0x80/0x80 drivers/video/fbdev/core/fbmem.c:68 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_file_open+0x84/0x410 security/security.c:1548 do_dentry_open+0x4ba/0x1290 fs/open.c:797 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_inode_permission+0xc4/0xf0 security/security.c:1253 chown_common+0x550/0x550 fs/open.c:629 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3229 [inline] path_openat+0x1e59/0x27d0 fs/namei.c:3346 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 retint_kernel+0x2b/0x2b expand_files+0x4a0/0x7a0 fs/file.c:201 do_filp_open+0x192/0x260 fs/namei.c:3373 may_open_dev+0xf0/0xf0 fs/namei.c:2821 atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:694 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7d0 fs/open.c:1148 file_open_root+0x400/0x400 fs/open.c:1129 _copy_to_user+0x126/0x160 lib/usercopy.c:31 put_timespec64+0xcb/0x120 kernel/time/time.c:812 ns_to_kernel_old_timeval+0x100/0x100 kernel/time/time.c:521 do_sys_open+0xc3/0x140 fs/open.c:1164 filp_open+0x70/0x70 fs/open.c:1117 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.4:16820 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.4 D28392 16820 7512 0x00000004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 atomic64_cmpxchg include/asm-generic/atomic-instrumented.h:1463 [inline] atomic_long_cmpxchg_release include/asm-generic/atomic-long.h:424 [inline] __mutex_unlock_slowpath+0xe2/0x660 kernel/locking/mutex.c:1249 spin_unlock include/linux/spinlock.h:393 [inline] chrdev_open+0xc4/0x5c0 fs/char_dev.c:402 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4579 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 get_fb_info.part.0+0x80/0x80 drivers/video/fbdev/core/fbmem.c:68 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_file_open+0x84/0x410 security/security.c:1548 do_dentry_open+0x4ba/0x1290 fs/open.c:797 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_inode_permission+0xc4/0xf0 security/security.c:1253 chown_common+0x550/0x550 fs/open.c:629 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3229 [inline] path_openat+0x1e59/0x27d0 fs/namei.c:3346 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 trace_hardirqs_on_thunk+0x1a/0x1c arch/x86/entry/thunk_64.S:41 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x463/0x620 kernel/locking/lockdep.c:3702 do_filp_open+0x192/0x260 fs/namei.c:3373 may_open_dev+0xf0/0xf0 fs/namei.c:2821 atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:694 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7d0 fs/open.c:1148 file_open_root+0x400/0x400 fs/open.c:1129 _copy_to_user+0x126/0x160 lib/usercopy.c:31 put_timespec64+0xcb/0x120 kernel/time/time.c:812 ns_to_kernel_old_timeval+0x100/0x100 kernel/time/time.c:521 do_sys_open+0xc3/0x140 fs/open.c:1164 filp_open+0x70/0x70 fs/open.c:1117 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.5:16818 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27032 16818 7663 0x00004004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 atomic64_cmpxchg include/asm-generic/atomic-instrumented.h:1463 [inline] atomic_long_cmpxchg_release include/asm-generic/atomic-long.h:424 [inline] __mutex_unlock_slowpath+0xe2/0x660 kernel/locking/mutex.c:1249 spin_unlock include/linux/spinlock.h:393 [inline] chrdev_open+0xc4/0x5c0 fs/char_dev.c:402 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4579 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 get_fb_info.part.0+0x80/0x80 drivers/video/fbdev/core/fbmem.c:68 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_file_open+0x84/0x410 security/security.c:1548 do_dentry_open+0x4ba/0x1290 fs/open.c:797 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_inode_permission+0xc4/0xf0 security/security.c:1253 chown_common+0x550/0x550 fs/open.c:629 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3229 [inline] path_openat+0x1e59/0x27d0 fs/namei.c:3346 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 do_filp_open+0x192/0x260 fs/namei.c:3373 may_open_dev+0xf0/0xf0 fs/namei.c:2821 atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:694 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7d0 fs/open.c:1148 file_open_root+0x400/0x400 fs/open.c:1129 _copy_to_user+0x126/0x160 lib/usercopy.c:31 put_timespec64+0xcb/0x120 kernel/time/time.c:812 ns_to_kernel_old_timeval+0x100/0x100 kernel/time/time.c:521 do_sys_open+0xc3/0x140 fs/open.c:1164 filp_open+0x70/0x70 fs/open.c:1117 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.5:16822 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.5 D27848 16822 7663 0x00004004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 __list_add_valid+0x4b/0xa0 lib/list_debug.c:26 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 atomic64_cmpxchg include/asm-generic/atomic-instrumented.h:1463 [inline] atomic_long_cmpxchg_release include/asm-generic/atomic-long.h:424 [inline] __mutex_unlock_slowpath+0xe2/0x660 kernel/locking/mutex.c:1249 spin_unlock include/linux/spinlock.h:393 [inline] chrdev_open+0xc4/0x5c0 fs/char_dev.c:402 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4579 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 get_fb_info.part.0+0x80/0x80 drivers/video/fbdev/core/fbmem.c:68 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_file_open+0x84/0x410 security/security.c:1548 do_dentry_open+0x4ba/0x1290 fs/open.c:797 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_inode_permission+0xc4/0xf0 security/security.c:1253 chown_common+0x550/0x550 fs/open.c:629 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3229 [inline] path_openat+0x1e59/0x27d0 fs/namei.c:3346 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 retint_kernel+0x2b/0x2b do_filp_open+0x192/0x260 fs/namei.c:3373 may_open_dev+0xf0/0xf0 fs/namei.c:2821 atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:694 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7d0 fs/open.c:1148 file_open_root+0x400/0x400 fs/open.c:1129 _copy_to_user+0x126/0x160 lib/usercopy.c:31 put_timespec64+0xcb/0x120 kernel/time/time.c:812 ns_to_kernel_old_timeval+0x100/0x100 kernel/time/time.c:521 do_sys_open+0xc3/0x140 fs/open.c:1164 filp_open+0x70/0x70 fs/open.c:1117 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 INFO: task syz-executor.2:16819 blocked for more than 143 seconds. Not tainted 5.7.0-rc5-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. syz-executor.2 D28392 16819 7308 0x00000004 Call Trace: context_switch kernel/sched/core.c:3367 [inline] __schedule+0x937/0x1ff0 kernel/sched/core.c:4083 __sched_text_start+0x8/0x8 schedule+0xd0/0x2a0 kernel/sched/core.c:4158 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:4217 __mutex_lock_common kernel/locking/mutex.c:1033 [inline] __mutex_lock+0x7ab/0x13c0 kernel/locking/mutex.c:1103 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 mutex_trylock+0x2c0/0x2c0 kernel/locking/mutex.c:126 atomic64_cmpxchg include/asm-generic/atomic-instrumented.h:1463 [inline] atomic_long_cmpxchg_release include/asm-generic/atomic-long.h:424 [inline] __mutex_unlock_slowpath+0xe2/0x660 kernel/locking/mutex.c:1249 spin_unlock include/linux/spinlock.h:393 [inline] chrdev_open+0xc4/0x5c0 fs/char_dev.c:402 lock_downgrade+0x840/0x840 kernel/locking/lockdep.c:4579 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 lock_fb_info include/linux/fb.h:637 [inline] fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 get_fb_info.part.0+0x80/0x80 drivers/video/fbdev/core/fbmem.c:68 chrdev_open+0x219/0x5c0 fs/char_dev.c:414 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_file_open+0x84/0x410 security/security.c:1548 do_dentry_open+0x4ba/0x1290 fs/open.c:797 cdev_put.part.0+0x50/0x50 fs/char_dev.c:364 security_inode_permission+0xc4/0xf0 security/security.c:1253 chown_common+0x550/0x550 fs/open.c:629 inode_permission+0xab/0x500 fs/namei.c:450 do_open fs/namei.c:3229 [inline] path_openat+0x1e59/0x27d0 fs/namei.c:3346 path_lookupat.isra.0+0x530/0x530 fs/namei.c:2332 do_filp_open+0x192/0x260 fs/namei.c:3373 may_open_dev+0xf0/0xf0 fs/namei.c:2821 atomic_try_cmpxchg include/asm-generic/atomic-instrumented.h:694 [inline] queued_spin_lock include/asm-generic/qspinlock.h:78 [inline] do_raw_spin_lock+0x129/0x2e0 kernel/locking/spinlock_debug.c:113 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x24/0x40 kernel/locking/spinlock.c:183 spin_unlock include/linux/spinlock.h:393 [inline] __alloc_fd+0x46d/0x600 fs/file.c:534 do_sys_openat2+0x585/0x7d0 fs/open.c:1148 file_open_root+0x400/0x400 fs/open.c:1129 _copy_to_user+0x126/0x160 lib/usercopy.c:31 put_timespec64+0xcb/0x120 kernel/time/time.c:812 ns_to_kernel_old_timeval+0x100/0x100 kernel/time/time.c:521 do_sys_open+0xc3/0x140 fs/open.c:1164 filp_open+0x70/0x70 fs/open.c:1117 __ia32_sys_clock_settime+0x260/0x260 kernel/time/posix-timers.c:1410 trace_hardirqs_off_caller+0x55/0x230 kernel/trace/trace_preemptirq.c:73 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Showing all locks held in the system: 1 lock held by khungtaskd/1140: #0: ffffffff899bea80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5754 1 lock held by in:imklog/6730: #0: ffff88809ca5ebb0 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:826 2 locks held by syz-executor.0/16810: 1 lock held by syz-executor.1/16805: #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: fb_release+0x4e/0x140 drivers/video/fbdev/core/fbmem.c:1447 1 lock held by syz-executor.4/16817: #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 1 lock held by syz-executor.4/16820: #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 1 lock held by syz-executor.5/16818: #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 1 lock held by syz-executor.5/16822: #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 1 lock held by syz-executor.2/16819: #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: lock_fb_info include/linux/fb.h:637 [inline] #0: ffff888218f1f078 (&fb_info->lock){+.+.}-{3:3}, at: fb_open+0xd3/0x430 drivers/video/fbdev/core/fbmem.c:1418 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 1140 Comm: khungtaskd Not tainted 5.7.0-rc5-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+0x188/0x20d lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101 lapic_can_unplug_cpu.cold+0x3b/0x3b nmi_trigger_cpumask_backtrace+0x231/0x27e lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0xa8c/0x1010 kernel/hung_task.c:289 reset_hung_task_detector+0x30/0x30 kernel/hung_task.c:243 kthread+0x388/0x470 kernel/kthread.c:268 kthread_mod_delayed_work+0x1a0/0x1a0 kernel/kthread.c:1090 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:351 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 16810 Comm: syz-executor.0 Not tainted 5.7.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline] RIP: 0010:check_kcov_mode kernel/kcov.c:153 [inline] RIP: 0010:write_comp_data+0x9/0x70 kernel/kcov.c:208 Code: 80 dc 13 00 00 48 8b 11 48 83 c2 01 48 39 d0 76 07 48 89 34 d1 48 89 11 c3 0f 1f 84 00 00 00 00 00 65 4c 8b 04 25 00 1f 02 00 <65> 8b 05 f8 ea 8e 7e a9 00 01 1f 00 75 51 41 8b 80 d8 13 00 00 83 RSP: 0018:ffffc90017017598 EFLAGS: 00000246 RAX: 0000000000040000 RBX: 0000000000000004 RCX: ffffffff83c34a4a RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000005 RBP: 0000000000000000 R08: ffff88809b6d4040 R09: ffffed10431ee884 R10: ffff888218f7441f R11: ffffed10431ee883 R12: ffff8880000a0004 R13: ffff8880000a0000 R14: 0000000000000000 R15: 000000000e7c9cb4 FS: 00007f7c7283e700(0000) GS:ffff8880ae600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f43f7a7e000 CR3: 00000000a8da3000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: vga16fb_fillrect+0x9ba/0x1960 drivers/video/fbdev/vga16fb.c:922 memcpy+0x39/0x60 mm/kasan/common.c:107 bit_clear_margins+0x2d5/0x4a0 drivers/video/fbdev/core/bitblit.c:232 bit_bmove+0x210/0x210 drivers/video/fbdev/core/bitblit.c:59 vesafb_probe.cold+0x1162/0x1162 fbcon_clear_margins+0x1de/0x240 drivers/video/fbdev/core/fbcon.c:1381 fbcon_switch+0xcde/0x16f0 drivers/video/fbdev/core/fbcon.c:2363 fbcon_set_def_font+0x370/0x370 drivers/video/fbdev/core/fbcon.c:2710 fbcon_cursor+0x477/0x650 drivers/video/fbdev/core/fbcon.c:1411 bit_clear+0x4e0/0x4e0 drivers/video/fbdev/core/fbcon.h:140 is_console_locked+0x5/0x10 kernel/printk/printk.c:2346 fbcon_set_origin+0x26/0x50 drivers/video/fbdev/core/fbcon.c:2938 redraw_screen+0x2ae/0x770 drivers/tty/vt/vt.c:1015 vesafb_probe.cold+0x1162/0x1162 respond_string+0x290/0x290 include/linux/tty_flip.h:27 fbcon_set_palette+0x3b1/0x4a0 drivers/video/fbdev/core/fbcon.c:2764 fbcon_modechanged+0x581/0x720 drivers/video/fbdev/core/fbcon.c:3000 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3047 fb_set_var+0xad0/0xd40 drivers/video/fbdev/core/fbmem.c:1056 fb_blank+0x190/0x190 drivers/video/fbdev/core/fbmem.c:1081 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] _raw_spin_unlock_irqrestore+0x62/0xe0 kernel/locking/spinlock.c:191 do_fb_ioctl+0x390/0x6e0 drivers/video/fbdev/core/fbmem.c:1109 fb_mmap+0x550/0x550 drivers/video/fbdev/core/fbmem.c:1383 tomoyo_execute_permission+0x470/0x470 security/tomoyo/file.c:168 __sanitizer_cov_trace_switch+0x45/0x70 kernel/kcov.c:310 ioctl_fioasync fs/ioctl.c:601 [inline] do_vfs_ioctl+0x50c/0x1360 fs/ioctl.c:704 ksys_dup3+0x3c0/0x3c0 include/linux/compiler.h:199 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1185 do_fb_ioctl+0x6e0/0x6e0 drivers/video/fbdev/core/fbmem.c:1169 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:771 __do_sys_ioctl fs/ioctl.c:780 [inline] __se_sys_ioctl fs/ioctl.c:778 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:778 __trace_hardirqs_on_caller kernel/locking/lockdep.c:3657 [inline] lockdep_hardirqs_on+0x463/0x620 kernel/locking/lockdep.c:3702 do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:295 entry_SYSCALL_64_after_hwframe+0x49/0xb3 RIP: 0033:0x45c829 Code: 0d b7 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 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f7c7283dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00000000004e4860 RCX: 000000000045c829 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000006 RBP: 000000000078c040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002f2 R14: 00000000004c54c8 R15: 00007f7c7283e6d4