From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-oi1-f207.google.com (mail-oi1-f207.google.com [209.85.167.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 80D3A4A21 for ; Sat, 1 Aug 2026 00:03:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785542607; cv=none; b=trRq5r0sqjG/t+YER3d5WcpHt273hLceqVM//Ga/5qYVYRoF/WeJdB0LsRTBmuURDKVLYFHj4YY3NGpOn7CunxTv8DYDCbdJKPfKW/0bRw9GcaiZrF+VKdU5I0EHtUQwo/saGRud15UwqBs/lrDu9O8FEXU9QP54oFja0SDSDdg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785542607; c=relaxed/simple; bh=pFUrZurBtciXvnqeMp216N6tYglL21j4Jdvl58CpHTg=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=seDitKEd8v3fXYV2d4mM4XCYyau1N5LAoQHIxOTsXiouYnBEtuR5mxqoFuxKD+sFjBp7zaW6S8qRi9dQvrmUn5eLK2o5wdixgSwjtui/0SoKbwjZz1kUYoFhllZ2cO1XhnV7nAiFVESboSxacPYNtjYcZjKTniOI/yhplBajYhA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.167.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-oi1-f207.google.com with SMTP id 5614622812f47-495b8120909so1932774b6e.1 for ; Fri, 31 Jul 2026 17:03:24 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1785542603; x=1786147403; h=content-type:to:from:subject:message-id:date:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=aPI602Y0g39NIKC38ICsLhKkZFI9nwbwdY786/RGUSw=; b=S4BzeFbs2uu7Dm3EmaxJNNUSdITpPLHadGoAG9htBSce9bVXuJwOBUX2FQNDL8ro5j cnU3UVshYUQhjNMRvfChzkfB3M/Naeh2Hey66fK05Qc5F1hqFGkAZwNmBB3mJ4XqtdCO LWaeYeHZgi8OYrXM/RiPXquJ5+obQBGD0lwUlDpBi84+doz/jXDVzMXB86TvfEwDwVcK 2koaOMiV8DSHE+tNJ7mKRBSME2tRI+gOnCPDIFOSTbXQqSesUjEGrzlemITriTbhybp3 cjHHT92ayb9k6RhviNqbFCUZJBZqYhpklwnqAW3iib3p9FsyTQ18Bp4+h52/8HKV98Rj 6rYQ== X-Forwarded-Encrypted: i=1; AHgh+RrMOQaDGMSSsu2PZl4TWrZrffCbg3kRCPqsaRYvFLB3sxGu7Nqe/YXrEQf5iI1+NZ+aifGS9/EAAMT4a/k=@vger.kernel.org X-Gm-Message-State: AOJu0YwIfywPAp4kE06j2+SH7mgd7r03IAwo7RCoDwZZEM6RolqKS1RY KTvL4B6TxvwQA5OWVTwPR/vebIJ48qDlVdBoLbl0M8/JmZS3qbvzA4G+5XXyLvke1AwDwlqhlcE 1c3zvx50xa/eC4DubmfgowuPPNpnC/6r4LvghKnub3bR8qrMB/KRf0bTH00M= Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6808:6c85:b0:495:f8a6:81f8 with SMTP id 5614622812f47-4af5e29cd37mr3787772b6e.13.1785542603307; Fri, 31 Jul 2026 17:03:23 -0700 (PDT) Date: Fri, 31 Jul 2026 17:03:23 -0700 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <6a6d37cb.f794c993.27aeb.0006.GAE@google.com> Subject: [syzbot] [serial?] possible deadlock in __refill_objects_node From: syzbot To: gregkh@linuxfoundation.org, jirislaby@kernel.org, linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 11028ab62899 Merge tag 'probes-fixes-v7.2-rc5' of git://gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=174625b9580000 kernel config: https://syzkaller.appspot.com/x/.config?x=145fa60d73086782 dashboard link: https://syzkaller.appspot.com/bug?extid=5cd85bfb5621212d8c2f compiler: gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/d900f083ada3/non_bootable_disk-11028ab6.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/e2be78614a29/vmlinux-11028ab6.xz kernel image: https://storage.googleapis.com/syzbot-assets/301a11d315af/bzImage-11028ab6.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+5cd85bfb5621212d8c2f@syzkaller.appspotmail.com ============================================================================= ====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Tainted: G L ------------------------------------------------------ syz.5.2538/15441 is trying to acquire lock: ffffffff8eaf40e0 (console_owner){-.-.}-{0:0}, at: console_trylock_spinning kernel/printk/printk.c:2026 [inline] ffffffff8eaf40e0 (console_owner){-.-.}-{0:0}, at: vprintk_emit+0x4c0/0x6b0 kernel/printk/printk.c:2478 but task is already holding lock: ffff888028139618 (&n->list_lock){-.-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:372 [inline] ffff888028139618 (&n->list_lock){-.-.}-{3:3}, at: free_partial mm/slub.c:8009 [inline] ffff888028139618 (&n->list_lock){-.-.}-{3:3}, at: __kmem_cache_shutdown+0x10c/0x330 mm/slub.c:8058 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (&n->list_lock){-.-.}-{3:3}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166 get_partial_node_bulk mm/slub.c:3744 [inline] __refill_objects_node+0x120/0xaa0 mm/slub.c:7169 refill_objects+0x58/0x410 mm/slub.c:7297 refill_sheaf mm/slub.c:2804 [inline] __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675 alloc_from_pcs mm/slub.c:4773 [inline] slab_alloc_node mm/slub.c:4905 [inline] __do_kmalloc_node mm/slub.c:5333 [inline] __kmalloc_noprof+0x66d/0x820 mm/slub.c:5359 _kmalloc_noprof include/linux/slab.h:992 [inline] tty_buffer_alloc+0x29f/0x320 drivers/tty/tty_buffer.c:187 __tty_buffer_request_room+0x129/0x2c0 drivers/tty/tty_buffer.c:280 __tty_insert_flip_string_flags+0xdb/0x3f0 drivers/tty/tty_buffer.c:316 tty_insert_flip_string_fixed_flag include/linux/tty_flip.h:35 [inline] tty_insert_flip_string include/linux/tty_flip.h:83 [inline] tty_insert_flip_string_and_push_buffer+0x9c/0x230 drivers/tty/tty_buffer.c:565 pty_write+0xd2/0x100 drivers/tty/pty.c:116 n_tty_write+0xa9e/0x1160 drivers/tty/n_tty.c:2388 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write.isra.0+0x4d2/0x890 drivers/tty/tty_io.c:1081 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #2 (&port->lock#2){-.-.}-{3:3}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166 class_spinlock_irqsave_constructor include/linux/spinlock.h:619 [inline] tty_port_tty_get+0x21/0x100 drivers/tty/tty_port.c:322 class_tty_port_tty_constructor include/linux/tty_port.h:293 [inline] tty_port_default_wakeup+0x15/0x60 drivers/tty/tty_port.c:66 serial8250_tx_chars+0x68f/0x860 drivers/tty/serial/8250/8250_port.c:1723 serial8250_handle_irq_locked+0x770/0x9a0 drivers/tty/serial/8250/8250_port.c:1837 serial8250_handle_irq.part.0+0xb4/0x530 drivers/tty/serial/8250/8250_port.c:1853 serial8250_handle_irq drivers/tty/serial/8250/8250_port.c:1849 [inline] serial8250_default_handle_irq+0xc2/0x280 drivers/tty/serial/8250/8250_port.c:1867 serial8250_interrupt+0xf8/0x1b0 drivers/tty/serial/8250/8250_core.c:86 __handle_irq_event_percpu+0x232/0x880 kernel/irq/handle.c:209 handle_irq_event_percpu kernel/irq/handle.c:246 [inline] handle_irq_event+0xab/0x1e0 kernel/irq/handle.c:263 handle_edge_irq+0x34c/0x950 kernel/irq/chip.c:859 generic_handle_irq_desc include/linux/irqdesc.h:188 [inline] handle_irq arch/x86/kernel/irq.c:209 [inline] call_irq_handler arch/x86/kernel/irq.c:265 [inline] __common_interrupt+0xd8/0x2f0 arch/x86/kernel/irq.c:280 common_interrupt+0xb9/0xe0 arch/x86/kernel/irq.c:273 asm_common_interrupt+0x26/0x40 arch/x86/include/asm/idtentry.h:665 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] _raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:198 spin_unlock_irqrestore include/linux/spinlock.h:408 [inline] uart_port_unlock_irqrestore include/linux/serial_core.h:790 [inline] uart_port_unlock_deref drivers/tty/serial/serial_core.c:91 [inline] uart_port_unlock_deref drivers/tty/serial/serial_core.c:88 [inline] uart_write+0x29d/0xb20 drivers/tty/serial/serial_core.c:630 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:1081 tty_write drivers/tty/tty_io.c:1102 [inline] redirected_tty_write drivers/tty/tty_io.c:1125 [inline] redirected_tty_write+0xd4/0x120 drivers/tty/tty_io.c:1105 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #1 (&port_lock_key){-.-.}-{3:3}: lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:166 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+0x790/0xe50 kernel/printk/printk.c:3269 console_flush_all kernel/printk/printk.c:3343 [inline] __console_flush_and_unlock kernel/printk/printk.c:3373 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3413 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:4208 univ8250_console_init+0x6f/0x80 drivers/tty/serial/8250/8250_core.c:515 console_init+0x3d5/0x5b0 kernel/printk/printk.c:4407 start_kernel+0x314/0x490 init/main.c:1112 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:3165 check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x136c/0x1a40 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 console_trylock_spinning kernel/printk/printk.c:2026 [inline] vprintk_emit+0x4d1/0x6b0 kernel/printk/printk.c:2478 _printk+0xcf/0x110 kernel/printk/printk.c:2504 __slab_bug+0x4f/0xb0 mm/slub.c:1144 slab_bug+0x5d/0x80 mm/slub.c:1155 list_slab_objects mm/slub.c:7978 [inline] free_partial mm/slub.c:8015 [inline] __kmem_cache_shutdown.cold+0x39/0x177 mm/slub.c:8058 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:3961 device_unregister+0x1d/0xe0 drivers/base/core.c:4002 unregister_virtio_device+0x39/0x60 drivers/virtio/virtio.c:594 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:523 dev_attr_store+0x58/0x80 drivers/base/core.c:2505 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+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f other info that might help us debug this: Chain exists of: console_owner --> &port->lock#2 --> &n->list_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&n->list_lock); lock(&port->lock#2); lock(&n->list_lock); lock(console_owner); *** DEADLOCK *** 9 locks held by syz.5.2538/15441: #0: ffff88805ac12ef0 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x2aa/0x380 fs/file.c:1259 #1: ffff88802f138450 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:739 #2: ffff888026b2d480 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:336 #3: ffffffff8f86c760 (pci_rescan_remove_lock){+.+.}-{4:4}, at: pci_stop_and_remove_bus_device_locked+0x12/0x20 drivers/pci/remove.c:135 #4: ffff8880231301f8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #4: ffff8880231301f8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline] #4: ffff8880231301f8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369 #5: ffff88802629b1b0 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1102 [inline] #5: ffff88802629b1b0 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1171 [inline] #5: ffff88802629b1b0 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1369 #6: ffffffff8ea7a230 (cpu_hotplug_lock){++++}-{0:0}, at: kmem_cache_destroy mm/slab_common.c:556 [inline] #6: ffffffff8ea7a230 (cpu_hotplug_lock){++++}-{0:0}, at: kmem_cache_destroy+0x4b/0x190 mm/slab_common.c:527 #7: ffffffff8ed88200 (slab_mutex){+.+.}-{4:4}, at: kmem_cache_destroy mm/slab_common.c:557 [inline] #7: ffffffff8ed88200 (slab_mutex){+.+.}-{4:4}, at: kmem_cache_destroy+0x59/0x190 mm/slab_common.c:527 #8: ffff888028139618 (&n->list_lock){-.-.}-{3:3}, at: spin_lock_irq include/linux/spinlock.h:372 [inline] #8: ffff888028139618 (&n->list_lock){-.-.}-{3:3}, at: free_partial mm/slub.c:8009 [inline] #8: ffff888028139618 (&n->list_lock){-.-.}-{3:3}, at: __kmem_cache_shutdown+0x10c/0x330 mm/slub.c:8058 stack backtrace: CPU: 2 UID: 0 PID: 15441 Comm: syz.5.2538 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: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_circular_bug.cold+0x178/0x1c7 kernel/locking/lockdep.c:2043 check_noncircular+0x146/0x160 kernel/locking/lockdep.c:2175 check_prev_add+0xeb/0xe60 kernel/locking/lockdep.c:3165 check_prevs_add kernel/locking/lockdep.c:3284 [inline] validate_chain kernel/locking/lockdep.c:3908 [inline] __lock_acquire+0x136c/0x1a40 kernel/locking/lockdep.c:5237 lock_acquire kernel/locking/lockdep.c:5868 [inline] lock_acquire+0x1b9/0x370 kernel/locking/lockdep.c:5825 console_trylock_spinning kernel/printk/printk.c:2026 [inline] vprintk_emit+0x4d1/0x6b0 kernel/printk/printk.c:2478 _printk+0xcf/0x110 kernel/printk/printk.c:2504 __slab_bug+0x4f/0xb0 mm/slub.c:1144 slab_bug+0x5d/0x80 mm/slub.c:1155 list_slab_objects mm/slub.c:7978 [inline] free_partial mm/slub.c:8015 [inline] __kmem_cache_shutdown.cold+0x39/0x177 mm/slub.c:8058 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:3961 device_unregister+0x1d/0xe0 drivers/base/core.c:4002 unregister_virtio_device+0x39/0x60 drivers/virtio/virtio.c:594 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:523 dev_attr_store+0x58/0x80 drivers/base/core.c:2505 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+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8bea79df99 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:00007f8beb5fc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8beaa25fa0 RCX: 00007f8bea79df99 RDX: 0000000000000001 RSI: 0000200000000800 RDI: 0000000000000004 RBP: 00007f8bea834ec4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8beaa26038 R14: 00007f8beaa25fa0 R15: 00007ffc98064e98 BUG virtio-gpu-vbufs (Tainted: G L ): Objects remaining on __kmem_cache_shutdown() ----------------------------------------------------------------------------- Object 0xffff88803d222000 @offset=0 Object 0xffff88803d222118 @offset=280 Object 0xffff88803d222230 @offset=560 Object 0xffff88803d222348 @offset=840 Object 0xffff88803d222460 @offset=1120 Object 0xffff88803d222578 @offset=1400 Object 0xffff88803d222690 @offset=1680 Object 0xffff88803d2227a8 @offset=1960 Slab 0xffffea0000f48880 objects=29 used=8 fp=0xffff88803d2228c0 flags=0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) ------------[ cut here ]------------ 1 WARNING: mm/slub.c:1244 at __slab_err+0x15/0x20 mm/slub.c:1244, CPU#2: syz.5.2538/15441 Modules linked in: CPU: 2 UID: 0 PID: 15441 Comm: syz.5.2538 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:1244 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 dc ba a2 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:ffffc90004e3f738 EFLAGS: 00010093 RAX: 0000000000000000 RBX: ffffc90004e3f788 RCX: ffffffff81c709af RDX: ffff88805bd02540 RSI: ffffffff81c709bd RDI: ffff88805bd02540 RBP: ffff888028139618 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000062616c53 R12: 0000000000001ea0 R13: ffff88803d223fb8 R14: ffff888028139600 R15: ffffea0000f48880 FS: 00007f8beb5fc6c0(0000) GS:ffff8880d5fdc000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00005605bceb4300 CR3: 0000000037c15000 CR4: 0000000000352ef0 Call Trace: list_slab_objects mm/slub.c:7994 [inline] free_partial mm/slub.c:8015 [inline] __kmem_cache_shutdown.cold+0x16e/0x177 mm/slub.c:8058 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:3961 device_unregister+0x1d/0xe0 drivers/base/core.c:4002 unregister_virtio_device+0x39/0x60 drivers/virtio/virtio.c:594 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:523 dev_attr_store+0x58/0x80 drivers/base/core.c:2505 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+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8bea79df99 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:00007f8beb5fc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f8beaa25fa0 RCX: 00007f8bea79df99 RDX: 0000000000000001 RSI: 0000200000000800 RDI: 0000000000000004 RBP: 00007f8bea834ec4 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8beaa26038 R14: 00007f8beaa25fa0 R15: 00007ffc98064e98 --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@googlegroups.com. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. If the report is already addressed, let syzbot know by replying with: #syz fix: exact-commit-title If you want to overwrite report's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the report is a duplicate of another one, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup