=============================================================================
======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
syz.3.512/7845 is trying to acquire lock:
ffffffff8ecf5cc0 (console_owner){-.-.}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:2026 [inline]
ffffffff8ecf5cc0 (console_owner){-.-.}-{0:0}, at: vprintk_emit+0x4c3/0x6b0 kernel/printk/printk.c:2478

but task is already holding lock:
ffff888027cf9618 (&n->list_lock){-.-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:377 [inline]
ffff888027cf9618 (&n->list_lock){-.-.}-{3:3}, at: free_partial mm/slub.c:8004 [inline]
ffff888027cf9618 (&n->list_lock){-.-.}-{3:3}, at: __kmem_cache_shutdown+0x10c/0x330 mm/slub.c:8053

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&n->list_lock){-.-.}-{3:3}:
       lock_acquire kernel/locking/lockdep.c:5886 [inline]
       lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:181
       get_from_partial_node+0x7d/0x5b0 mm/slub.c:3819
       get_from_partial mm/slub.c:3949 [inline]
       ___slab_alloc+0x78/0x800 mm/slub.c:4461
       slab_alloc_node mm/slub.c:4910 [inline]
       kmem_cache_alloc_noprof+0x3a9/0x6a0 mm/slub.c:4933
       kmem_alloc_batch+0x49/0x170 lib/debugobjects.c:371
       fill_pool lib/debugobjects.c:420 [inline]
       debug_objects_fill_pool lib/debugobjects.c:780 [inline]
       debug_objects_fill_pool+0x24d/0x550 lib/debugobjects.c:758
       debug_object_activate+0x103/0x4b0 lib/debugobjects.c:869
       debug_work_activate kernel/workqueue.c:684 [inline]
       insert_work+0x2e/0x230 kernel/workqueue.c:2269
       __queue_work+0xa60/0x1370 kernel/workqueue.c:2448
       call_timer_fn+0x198/0x5f0 kernel/time/timer.c:1748
       expire_timers kernel/time/timer.c:1794 [inline]
       __run_timers+0x570/0xb00 kernel/time/timer.c:2374
       __run_timer_base kernel/time/timer.c:2386 [inline]
       __run_timer_base kernel/time/timer.c:2378 [inline]
       run_timer_base+0x114/0x190 kernel/time/timer.c:2395
       run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405
       handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
       __do_softirq kernel/softirq.c:679 [inline]
       invoke_softirq kernel/softirq.c:519 [inline]
       __irq_exit_rcu+0x194/0x210 kernel/softirq.c:767
       irq_exit_rcu+0x9/0x30 kernel/softirq.c:784
       instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
       sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
       asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
       lock_acquire+0x5e/0x370 kernel/locking/lockdep.c:5851
       rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
       rcu_read_lock include/linux/rcupdate.h:840 [inline]
       class_rcu_constructor include/linux/rcupdate.h:1183 [inline]
       unwind_next_frame+0xd1/0x2090 arch/x86/kernel/unwind_orc.c:495
       __unwind_start+0x3cd/0x7e0 arch/x86/kernel/unwind_orc.c:787
       unwind_start arch/x86/include/asm/unwind.h:64 [inline]
       arch_stack_walk+0x73/0xf0 arch/x86/kernel/stacktrace.c:24
       stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
       kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
       kasan_save_track+0x14/0x30 mm/kasan/common.c:78
       unpoison_slab_object mm/kasan/common.c:340 [inline]
       __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
       kasan_slab_alloc include/linux/kasan.h:253 [inline]
       slab_post_alloc_hook mm/slub.c:4586 [inline]
       slab_alloc_node mm/slub.c:4919 [inline]
       kmem_cache_alloc_noprof+0x26b/0x6a0 mm/slub.c:4933
       __kernfs_new_node+0xd2/0xa10 fs/kernfs/dir.c:665
       kernfs_new_node+0x117/0x150 fs/kernfs/dir.c:751
       __kernfs_create_file+0x53/0x350 fs/kernfs/file.c:1050
       sysfs_add_file_mode_ns+0x207/0x3c0 fs/sysfs/file.c:316
       sysfs_merge_group+0x194/0x340 fs/sysfs/group.c:382
       dpm_sysfs_add+0x237/0x280 drivers/base/power/sysfs.c:704
       device_add+0x9f4/0x1970 drivers/base/core.c:3721
       regulator_register+0x16fb/0x2b10 drivers/regulator/core.c:6211
       devm_regulator_register+0x59/0xe0 drivers/regulator/devres.c:476
       dummy_regulator_probe+0xaf/0x120 drivers/regulator/dummy.c:48
       faux_probe+0x7c/0x1e0 drivers/base/faux.c:48
       call_driver_probe drivers/base/dd.c:628 [inline]
       really_probe+0x241/0xa60 drivers/base/dd.c:706
       __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
       driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
       __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
       bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
       __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
       device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
       bus_probe_device+0x64/0x160 drivers/base/bus.c:620
       device_add+0x121d/0x1970 drivers/base/core.c:3776
       faux_device_create_with_groups+0x1d9/0x300 drivers/base/faux.c:161
       regulator_dummy_init+0x1e/0x40 drivers/regulator/dummy.c:67
       regulator_init+0x14e/0x180 drivers/regulator/core.c:6790
       do_one_initcall+0x11c/0x6f0 init/main.c:1353
       do_initcall_level init/main.c:1415 [inline]
       do_initcalls init/main.c:1431 [inline]
       do_basic_setup init/main.c:1451 [inline]
       kernel_init_freeable+0x6ea/0x7b0 init/main.c:1666
       kernel_init+0x21/0x1e0 init/main.c:1556
       ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #3 (&pool->lock){-.-.}-{2:2}:
       lock_acquire kernel/locking/lockdep.c:5886 [inline]
       lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
       __raw_spin_lock include/linux/spinlock_api_smp.h:190 [inline]
       _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:173
       __queue_work+0x2ef/0x1370 kernel/workqueue.c:2408
       queue_work_on+0x1a9/0x1e0 kernel/workqueue.c:2501
       queue_work include/linux/workqueue.h:699 [inline]
       rpm_suspend+0xf6b/0x1220 drivers/base/power/runtime.c:685
       rpm_idle+0x60c/0x790 drivers/base/power/runtime.c:559
       __pm_runtime_idle+0xba/0x1a0 drivers/base/power/runtime.c:1129
       pm_runtime_put include/linux/pm_runtime.h:551 [inline]
       __device_attach+0x37e/0x4d0 drivers/base/dd.c:1116
       device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
       bus_probe_device+0x64/0x160 drivers/base/bus.c:620
       device_add+0x121d/0x1970 drivers/base/core.c:3776
       serial_base_port_add+0x227/0x2b0 drivers/tty/serial/serial_base_bus.c:186
       serial_core_port_device_add drivers/tty/serial/serial_core.c:3275 [inline]
       serial_core_register_port+0x13c/0x16f0 drivers/tty/serial/serial_core.c:3314
       serial8250_register_8250_port+0x15af/0x2330 drivers/tty/serial/8250/8250_core.c:828
       serial_pnp_probe+0x436/0x930 drivers/tty/serial/8250/8250_pnp.c:480
       pnp_device_probe+0x2b3/0x4a0 drivers/pnp/driver.c:111
       call_driver_probe drivers/base/dd.c:628 [inline]
       really_probe+0x241/0xa60 drivers/base/dd.c:706
       __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
       driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
       __driver_attach+0x21f/0x5b0 drivers/base/dd.c:1292
       bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:383
       bus_add_driver+0x305/0x5b0 drivers/base/bus.c:763
       driver_register+0x1e2/0x360 drivers/base/driver.c:174
       serial8250_init+0xcc/0x1c0 drivers/tty/serial/8250/8250_platform.c:317
       do_one_initcall+0x11c/0x6f0 init/main.c:1353
       do_initcall_level init/main.c:1415 [inline]
       do_initcalls init/main.c:1431 [inline]
       do_basic_setup init/main.c:1451 [inline]
       kernel_init_freeable+0x6ea/0x7b0 init/main.c:1666
       kernel_init+0x21/0x1e0 init/main.c:1556
       ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

-> #2 (&dev->power.lock){-.-.}-{3:3}:
       lock_acquire kernel/locking/lockdep.c:5886 [inline]
       lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:181
       __pm_runtime_resume+0xa9/0x170 drivers/base/power/runtime.c:1196
       pm_runtime_get include/linux/pm_runtime.h:494 [inline]
       __uart_start+0x1b0/0x510 drivers/tty/serial/serial_core.c:149
       uart_write+0x211/0xb20 drivers/tty/serial/serial_core.c:629
       process_output_block drivers/tty/n_tty.c:557 [inline]
       n_tty_write+0x431/0x1160 drivers/tty/n_tty.c:2366
       iterate_tty_write drivers/tty/tty_io.c:1006 [inline]
       file_tty_write.isra.0+0x4d2/0x890 drivers/tty/tty_io.c:1054
       tty_write drivers/tty/tty_io.c:1075 [inline]
       redirected_tty_write drivers/tty/tty_io.c:1098 [inline]
       redirected_tty_write+0xd4/0x120 drivers/tty/tty_io.c:1078
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x6af/0x1050 fs/read_write.c:687
       ksys_write+0x12a/0x250 fs/read_write.c:739
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&port_lock_key){-.-.}-{3:3}:
       lock_acquire kernel/locking/lockdep.c:5886 [inline]
       lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:155 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:181
       uart_port_lock_irqsave include/linux/serial_core.h:719 [inline]
       serial8250_console_write+0x177/0x1a50 drivers/tty/serial/8250/8250_port.c:3344
       console_emit_next_record kernel/printk/printk.c:3183 [inline]
       console_flush_one_record+0x78e/0xf10 kernel/printk/printk.c:3268
       console_flush_all kernel/printk/printk.c:3350 [inline]
       __console_flush_and_unlock kernel/printk/printk.c:3380 [inline]
       console_unlock+0x103/0x260 kernel/printk/printk.c:3420
       vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2479
       _printk+0xcf/0x110 kernel/printk/printk.c:2504
       register_console.cold+0xc0/0x248 kernel/printk/printk.c:4212
       univ8250_console_init+0x6f/0x80 drivers/tty/serial/8250/8250_core.c:515
       console_init+0x3d5/0x5b0 kernel/printk/printk.c:4411
       start_kernel+0x314/0x490 init/main.c:1118
       x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
       x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
       common_startup_64+0x13e/0x158

-> #0 (console_owner){-.-.}-{0:0}:
       check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3181
       check_prevs_add kernel/locking/lockdep.c:3300 [inline]
       validate_chain kernel/locking/lockdep.c:3924 [inline]
       __lock_acquire+0x1492/0x1ec0 kernel/locking/lockdep.c:5253
       lock_acquire kernel/locking/lockdep.c:5886 [inline]
       lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
       console_trylock_spinning kernel/printk/printk.c:2026 [inline]
       vprintk_emit+0x4d4/0x6b0 kernel/printk/printk.c:2478
       _printk+0xcf/0x110 kernel/printk/printk.c:2504
       __slab_bug+0x4f/0xb0 mm/slub.c:1145
       slab_bug+0x5d/0x80 mm/slub.c:1156
       list_slab_objects mm/slub.c:7973 [inline]
       free_partial mm/slub.c:8010 [inline]
       __kmem_cache_shutdown.cold+0x39/0x177 mm/slub.c:8053
       kmem_cache_destroy mm/slab_common.c:569 [inline]
       kmem_cache_destroy+0x73/0x190 mm/slab_common.c:527
       virtio_gpu_free_vbufs+0x38/0x80 drivers/gpu/drm/virtio/virtgpu_vq.c:86
       virtio_gpu_release+0x5c/0x1c0 drivers/gpu/drm/virtio/virtgpu_kms.c:312
       drm_dev_release drivers/gpu/drm/drm_drv.c:912 [inline]
       kref_put include/linux/kref.h:65 [inline]
       drm_dev_put.part.0+0xbd/0x140 drivers/gpu/drm/drm_drv.c:948
       drm_dev_put+0x1f/0x30 drivers/gpu/drm/drm_drv.c:947
       virtio_dev_remove+0xb8/0x170 drivers/virtio/virtio.c:375
       device_remove+0xcb/0x180 drivers/base/dd.c:616
       __device_release_driver drivers/base/dd.c:1349 [inline]
       device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
       bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
       device_del+0x376/0x9b0 drivers/base/core.c:3965
       device_unregister+0x1d/0xe0 drivers/base/core.c:4006
       unregister_virtio_device+0x39/0x60 drivers/virtio/virtio.c:607
       virtio_pci_remove+0x7c/0x110 drivers/virtio/virtio_pci_common.c:758
       pci_device_remove+0xb2/0x1d0 drivers/pci/pci-driver.c:512
       device_remove+0xcb/0x180 drivers/base/dd.c:616
       __device_release_driver drivers/base/dd.c:1349 [inline]
       device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
       pci_stop_dev drivers/pci/remove.c:27 [inline]
       pci_stop_bus_device+0x120/0x160 drivers/pci/remove.c:93
       pci_stop_and_remove_bus_device+0x58/0xa0 drivers/pci/remove.c:128
       pci_stop_and_remove_bus_device_locked+0x1a/0x20 drivers/pci/remove.c:136
       remove_store+0x123/0x140 drivers/pci/pci-sysfs.c:524
       dev_attr_store+0x58/0x80 drivers/base/core.c:2509
       sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
       kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
       new_sync_write fs/read_write.c:595 [inline]
       vfs_write+0x6af/0x1050 fs/read_write.c:687
       ksys_write+0x12a/0x250 fs/read_write.c:739
       do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
       do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  console_owner --> &pool->lock --> &n->list_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&n->list_lock);
                               lock(&pool->lock);
                               lock(&n->list_lock);
  lock(console_owner);

 *** DEADLOCK ***

locks held by syz.3.512/7845: 9, last CPU#2:
 #0: ffff8880362e3970 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259
 #1: ffff888027c3a460 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739
 #2: ffff88803d94bc80 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:336
 #3: ffffffff8fa7d5e0 (pci_rescan_remove_lock){+.+.}-{4:4}, at: pci_stop_and_remove_bus_device_locked+0x12/0x20 drivers/pci/remove.c:135
 #4: ffff8880230b01f8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
 #4: ffff8880230b01f8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
 #4: ffff8880230b01f8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
 #5: ffff8880266171b0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1104 [inline]
 #5: ffff8880266171b0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline]
 #5: ffff8880266171b0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369
 #6: ffffffff8ec7a830 (cpu_hotplug_lock){++++}-{0:0}, at: kmem_cache_destroy mm/slab_common.c:556 [inline]
 #6: ffffffff8ec7a830 (cpu_hotplug_lock){++++}-{0:0}, at: kmem_cache_destroy+0x4b/0x190 mm/slab_common.c:527
 #7: ffffffff8ef940c0 (slab_mutex){+.+.}-{4:4}, at: kmem_cache_destroy mm/slab_common.c:557 [inline]
 #7: ffffffff8ef940c0 (slab_mutex){+.+.}-{4:4}, at: kmem_cache_destroy+0x59/0x190 mm/slab_common.c:527
 #8: ffff888027cf9618 (&n->list_lock){-.-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:377 [inline]
 #8: ffff888027cf9618 (&n->list_lock){-.-.}-{3:3}, at: free_partial mm/slub.c:8004 [inline]
 #8: ffff888027cf9618 (&n->list_lock){-.-.}-{3:3}, at: __kmem_cache_shutdown+0x10c/0x330 mm/slub.c:8053

stack backtrace:
CPU: 2 UID: 0 PID: 7845 Comm: syz.3.512 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_circular_bug.cold+0x178/0x1be kernel/locking/lockdep.c:2059
 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2191
 check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3181
 check_prevs_add kernel/locking/lockdep.c:3300 [inline]
 validate_chain kernel/locking/lockdep.c:3924 [inline]
 __lock_acquire+0x1492/0x1ec0 kernel/locking/lockdep.c:5253
 lock_acquire kernel/locking/lockdep.c:5886 [inline]
 lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5843
 console_trylock_spinning kernel/printk/printk.c:2026 [inline]
 vprintk_emit+0x4d4/0x6b0 kernel/printk/printk.c:2478
 _printk+0xcf/0x110 kernel/printk/printk.c:2504
 __slab_bug+0x4f/0xb0 mm/slub.c:1145
 slab_bug+0x5d/0x80 mm/slub.c:1156
 list_slab_objects mm/slub.c:7973 [inline]
 free_partial mm/slub.c:8010 [inline]
 __kmem_cache_shutdown.cold+0x39/0x177 mm/slub.c:8053
 kmem_cache_destroy mm/slab_common.c:569 [inline]
 kmem_cache_destroy+0x73/0x190 mm/slab_common.c:527
 virtio_gpu_free_vbufs+0x38/0x80 drivers/gpu/drm/virtio/virtgpu_vq.c:86
 virtio_gpu_release+0x5c/0x1c0 drivers/gpu/drm/virtio/virtgpu_kms.c:312
 drm_dev_release drivers/gpu/drm/drm_drv.c:912 [inline]
 kref_put include/linux/kref.h:65 [inline]
 drm_dev_put.part.0+0xbd/0x140 drivers/gpu/drm/drm_drv.c:948
 drm_dev_put+0x1f/0x30 drivers/gpu/drm/drm_drv.c:947
 virtio_dev_remove+0xb8/0x170 drivers/virtio/virtio.c:375
 device_remove+0xcb/0x180 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
 device_del+0x376/0x9b0 drivers/base/core.c:3965
 device_unregister+0x1d/0xe0 drivers/base/core.c:4006
 unregister_virtio_device+0x39/0x60 drivers/virtio/virtio.c:607
 virtio_pci_remove+0x7c/0x110 drivers/virtio/virtio_pci_common.c:758
 pci_device_remove+0xb2/0x1d0 drivers/pci/pci-driver.c:512
 device_remove+0xcb/0x180 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
 pci_stop_dev drivers/pci/remove.c:27 [inline]
 pci_stop_bus_device+0x120/0x160 drivers/pci/remove.c:93
 pci_stop_and_remove_bus_device+0x58/0xa0 drivers/pci/remove.c:128
 pci_stop_and_remove_bus_device_locked+0x1a/0x20 drivers/pci/remove.c:136
 remove_store+0x123/0x140 drivers/pci/pci-sysfs.c:524
 dev_attr_store+0x58/0x80 drivers/base/core.c:2509
 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6af/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f883db9e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f883eb1c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f883de26090 RCX: 00007f883db9e159
RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000008
RBP: 00007f883dc35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f883de26128 R14: 00007f883de26090 R15: 00007fffac9c6d58
 </TASK>
BUG virtio-gpu-vbufs (Tainted: G             L     ): Objects remaining on __kmem_cache_shutdown()
-----------------------------------------------------------------------------

Object 0xffff888027fd0af0 @offset=2800
Object 0xffff888027fd0c08 @offset=3080
Slab 0xffffea00009ff400 objects=29 used=2 fp=0xffff888027fd1180 flags=0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
------------[ cut here ]------------
1
WARNING: mm/slub.c:1245 at __slab_err+0x15/0x20 mm/slub.c:1245, CPU#2: syz.3.512/7845
Modules linked in:

CPU: 2 UID: 0 PID: 7845 Comm: syz.3.512 Tainted: G    B        L      syzkaller #0 PREEMPT(full) 
Tainted: [B]=BAD_PAGE, [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:__slab_err+0x15/0x20 mm/slub.c:1245
Code: 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e8 5b fd ff ff be 01 00 00 00 bf 05 00 00 00 e8 9c 14 a3 00 90 <0f> 0b 90 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90003aaf740 EFLAGS: 00010046
RAX: 0000000000080000 RBX: ffffc90003aaf790 RCX: ffffc9002ffea000
RDX: 0000000000080000 RSI: ffffffff81c769bd RDI: ffff88805dc88000
RBP: ffff888027cf9618 R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000001ea0
R13: ffff888027fd1fb8 R14: ffff888027cf9600 R15: ffffea00009ff400
FS:  00007f883eb1c6c0(0000) GS:ffff8880d5da2000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8fc8832ff8 CR3: 000000005ad1b000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 list_slab_objects mm/slub.c:7989 [inline]
 free_partial mm/slub.c:8010 [inline]
 __kmem_cache_shutdown.cold+0x16e/0x177 mm/slub.c:8053
 kmem_cache_destroy mm/slab_common.c:569 [inline]
 kmem_cache_destroy+0x73/0x190 mm/slab_common.c:527
 virtio_gpu_free_vbufs+0x38/0x80 drivers/gpu/drm/virtio/virtgpu_vq.c:86
 virtio_gpu_release+0x5c/0x1c0 drivers/gpu/drm/virtio/virtgpu_kms.c:312
 drm_dev_release drivers/gpu/drm/drm_drv.c:912 [inline]
 kref_put include/linux/kref.h:65 [inline]
 drm_dev_put.part.0+0xbd/0x140 drivers/gpu/drm/drm_drv.c:948
 drm_dev_put+0x1f/0x30 drivers/gpu/drm/drm_drv.c:947
 virtio_dev_remove+0xb8/0x170 drivers/virtio/virtio.c:375
 device_remove+0xcb/0x180 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
 device_del+0x376/0x9b0 drivers/base/core.c:3965
 device_unregister+0x1d/0xe0 drivers/base/core.c:4006
 unregister_virtio_device+0x39/0x60 drivers/virtio/virtio.c:607
 virtio_pci_remove+0x7c/0x110 drivers/virtio/virtio_pci_common.c:758
 pci_device_remove+0xb2/0x1d0 drivers/pci/pci-driver.c:512
 device_remove+0xcb/0x180 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
 pci_stop_dev drivers/pci/remove.c:27 [inline]
 pci_stop_bus_device+0x120/0x160 drivers/pci/remove.c:93
 pci_stop_and_remove_bus_device+0x58/0xa0 drivers/pci/remove.c:128
 pci_stop_and_remove_bus_device_locked+0x1a/0x20 drivers/pci/remove.c:136
 remove_store+0x123/0x140 drivers/pci/pci-sysfs.c:524
 dev_attr_store+0x58/0x80 drivers/base/core.c:2509
 sysfs_kf_write+0xf2/0x150 fs/sysfs/file.c:145
 kernfs_fop_write_iter+0x3e0/0x5f0 fs/kernfs/file.c:345
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6af/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f883db9e159
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f883eb1c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f883de26090 RCX: 00007f883db9e159
RDX: 0000000000000001 RSI: 00002000000000c0 RDI: 0000000000000008
RBP: 00007f883dc35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f883de26128 R14: 00007f883de26090 R15: 00007fffac9c6d58
 </TASK>