Re: [syzbot] [io-uring?] kernel BUG in __io_remove_buffers
From: Jens Axboe
Date: Fri Apr 05 2024 - 22:08:46 EST
On 4/3/24 5:03 PM, syzbot wrote:
> Hello,
>
> syzbot tried to test the proposed patch but the build/boot failed:
>
> perboard
> [ 7.926982][ T1] usbcore: registered new interface driver dln2
> [ 7.928671][ T1] usbcore: registered new interface driver pn533_usb
> [ 7.935981][ T1] nfcsim 0.2 initialized
> [ 7.937582][ T1] usbcore: registered new interface driver port100
> [ 7.939440][ T1] usbcore: registered new interface driver nfcmrvl
> [ 7.947210][ T1] Loading iSCSI transport class v2.0-870.
> [ 7.968081][ T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
> [ 7.978141][ T1] ------------[ cut here ]------------
> [ 7.979719][ T1] refcount_t: decrement hit 0; leaking memory.
> [ 7.981758][ T1] WARNING: CPU: 0 PID: 1 at lib/refcount.c:31 refcount_warn_saturate+0xfa/0x1d0
> [ 7.984304][ T1] Modules linked in:
> [ 7.985206][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc2-syzkaller-00062-g25d658afbb9f #0
> [ 7.987566][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
> [ 7.989580][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
> [ 7.991289][ T1] Code: b2 00 00 00 e8 67 f3 e9 fc 5b 5d c3 cc cc cc cc e8 5b f3 e9 fc c6 05 73 24 e8 0a 01 90 48 c7 c7 40 34 1f 8c e8 67 8e ac fc 90 <0f> 0b 90 90 eb d9 e8 3b f3 e9 fc c6 05 50 24 e8 0a 01 90 48 c7 c7
> [ 7.995319][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
> [ 7.996425][ T1] RAX: 4d5c6abb0d962900 RBX: ffff8880215f782c RCX: ffff8880166d0000
> [ 7.998305][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
> [ 7.999479][ T1] RBP: 0000000000000004 R08: ffffffff8157ffc2 R09: fffffbfff1c39af8
> [ 8.001772][ T1] R10: dffffc0000000000 R11: fffffbfff1c39af8 R12: ffffea000502cdc0
> [ 8.004141][ T1] R13: ffffea000502cdc8 R14: 1ffffd4000a059b9 R15: 0000000000000000
> [ 8.006063][ T1] FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
> [ 8.007727][ T1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 8.009976][ T1] CR2: ffff88823ffff000 CR3: 000000000e134000 CR4: 00000000003506f0
> [ 8.011700][ T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [ 8.013384][ T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [ 8.015782][ T1] Call Trace:
> [ 8.016883][ T1] <TASK>
> [ 8.017827][ T1] ? __warn+0x163/0x4e0
> [ 8.019345][ T1] ? refcount_warn_saturate+0xfa/0x1d0
> [ 8.021058][ T1] ? report_bug+0x2b3/0x500
> [ 8.022280][ T1] ? refcount_warn_saturate+0xfa/0x1d0
> [ 8.024027][ T1] ? handle_bug+0x3e/0x70
> [ 8.025284][ T1] ? exc_invalid_op+0x1a/0x50
> [ 8.026551][ T1] ? asm_exc_invalid_op+0x1a/0x20
> [ 8.027878][ T1] ? __warn_printk+0x292/0x360
> [ 8.029272][ T1] ? refcount_warn_saturate+0xfa/0x1d0
> [ 8.030730][ T1] ? refcount_warn_saturate+0xf9/0x1d0
> [ 8.032217][ T1] __free_pages_ok+0xc60/0xd90
> [ 8.033265][ T1] make_alloc_exact+0xa3/0xf0
> [ 8.034312][ T1] vring_alloc_queue_split+0x20a/0x600
> [ 8.035607][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
> [ 8.036997][ T1] ? vp_find_vqs+0x4c/0x4e0
> [ 8.038142][ T1] ? virtscsi_probe+0x3ea/0xf60
> [ 8.039207][ T1] ? virtio_dev_probe+0x991/0xaf0
> [ 8.040304][ T1] ? really_probe+0x2b8/0xad0
> [ 8.041140][ T1] ? driver_probe_device+0x50/0x430
> [ 8.042068][ T1] vring_create_virtqueue_split+0xc6/0x310
> [ 8.042973][ T1] ? ret_from_fork+0x4b/0x80
> [ 8.044035][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
> [ 8.045362][ T1] vring_create_virtqueue+0xca/0x110
> [ 8.046384][ T1] ? __pfx_vp_notify+0x10/0x10
> [ 8.047405][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.048436][ T1] setup_vq+0xe9/0x2d0
> [ 8.049363][ T1] ? __pfx_vp_notify+0x10/0x10
> [ 8.050238][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.051200][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.053099][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.054362][ T1] vp_setup_vq+0xbf/0x330
> [ 8.055098][ T1] ? __pfx_vp_config_changed+0x10/0x10
> [ 8.056155][ T1] ? ioread16+0x2f/0x90
> [ 8.057127][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.057929][ T1] vp_find_vqs_msix+0x8b2/0xc80
> [ 8.058857][ T1] vp_find_vqs+0x4c/0x4e0
> [ 8.059767][ T1] virtscsi_init+0x8db/0xd00
> [ 8.060631][ T1] ? __pfx_virtscsi_init+0x10/0x10
> [ 8.061568][ T1] ? __pfx_default_calc_sets+0x10/0x10
> [ 8.062509][ T1] ? scsi_host_alloc+0xa57/0xea0
> [ 8.063697][ T1] ? vp_get+0xfd/0x140
> [ 8.064484][ T1] virtscsi_probe+0x3ea/0xf60
> [ 8.065484][ T1] ? __pfx_virtscsi_probe+0x10/0x10
> [ 8.066504][ T1] ? kernfs_add_one+0x156/0x8b0
> [ 8.067579][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
> [ 8.069445][ T1] ? virtio_features_ok+0x10c/0x270
> [ 8.070687][ T1] virtio_dev_probe+0x991/0xaf0
> [ 8.071903][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
> [ 8.073120][ T1] really_probe+0x2b8/0xad0
> [ 8.074086][ T1] __driver_probe_device+0x1a2/0x390
> [ 8.075198][ T1] driver_probe_device+0x50/0x430
> [ 8.076215][ T1] __driver_attach+0x45f/0x710
> [ 8.077779][ T1] ? __pfx___driver_attach+0x10/0x10
> [ 8.078838][ T1] bus_for_each_dev+0x239/0x2b0
> [ 8.080219][ T1] ? __pfx___driver_attach+0x10/0x10
> [ 8.081427][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
> [ 8.082648][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
> [ 8.084332][ T1] bus_add_driver+0x347/0x620
> [ 8.085542][ T1] driver_register+0x23a/0x320
> [ 8.086355][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
> [ 8.087517][ T1] virtio_scsi_init+0x65/0xe0
> [ 8.088253][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
> [ 8.089537][ T1] do_one_initcall+0x248/0x880
> [ 8.090403][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
> [ 8.091597][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
> [ 8.093212][ T1] ? __pfx_do_one_initcall+0x10/0x10
> [ 8.094289][ T1] ? __pfx_parse_args+0x10/0x10
> [ 8.095147][ T1] ? do_initcalls+0x1c/0x80
> [ 8.096320][ T1] ? rcu_is_watching+0x15/0xb0
> [ 8.097696][ T1] do_initcall_level+0x157/0x210
> [ 8.098851][ T1] do_initcalls+0x3f/0x80
> [ 8.099669][ T1] kernel_init_freeable+0x435/0x5d0
> [ 8.100419][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
> [ 8.101767][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
> [ 8.103417][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.104551][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.105480][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.106672][ T1] kernel_init+0x1d/0x2b0
> [ 8.107961][ T1] ret_from_fork+0x4b/0x80
> [ 8.108943][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.109758][ T1] ret_from_fork_asm+0x1a/0x30
> [ 8.111216][ T1] </TASK>
> [ 8.111818][ T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
> [ 8.113547][ T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc2-syzkaller-00062-g25d658afbb9f #0
> [ 8.114525][ T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
> [ 8.114525][ T1] Call Trace:
> [ 8.114525][ T1] <TASK>
> [ 8.114525][ T1] dump_stack_lvl+0x241/0x360
> [ 8.114525][ T1] ? __pfx_dump_stack_lvl+0x10/0x10
> [ 8.114525][ T1] ? __pfx__printk+0x10/0x10
> [ 8.114525][ T1] ? _printk+0xd5/0x120
> [ 8.114525][ T1] ? vscnprintf+0x5d/0x90
> [ 8.114525][ T1] panic+0x349/0x860
> [ 8.124011][ T1] ? __warn+0x172/0x4e0
> [ 8.124011][ T1] ? __pfx_panic+0x10/0x10
> [ 8.124011][ T1] ? show_trace_log_lvl+0x4e6/0x520
> [ 8.124011][ T1] ? ret_from_fork_asm+0x1a/0x30
> [ 8.124011][ T1] __warn+0x346/0x4e0
> [ 8.124011][ T1] ? refcount_warn_saturate+0xfa/0x1d0
> [ 8.124011][ T1] report_bug+0x2b3/0x500
> [ 8.124011][ T1] ? refcount_warn_saturate+0xfa/0x1d0
> [ 8.124011][ T1] handle_bug+0x3e/0x70
> [ 8.133902][ T1] exc_invalid_op+0x1a/0x50
> [ 8.133902][ T1] asm_exc_invalid_op+0x1a/0x20
> [ 8.133902][ T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
> [ 8.133902][ T1] Code: b2 00 00 00 e8 67 f3 e9 fc 5b 5d c3 cc cc cc cc e8 5b f3 e9 fc c6 05 73 24 e8 0a 01 90 48 c7 c7 40 34 1f 8c e8 67 8e ac fc 90 <0f> 0b 90 90 eb d9 e8 3b f3 e9 fc c6 05 50 24 e8 0a 01 90 48 c7 c7
> [ 8.133902][ T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
> [ 8.133902][ T1] RAX: 4d5c6abb0d962900 RBX: ffff8880215f782c RCX: ffff8880166d0000
> [ 8.143997][ T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
> [ 8.143997][ T1] RBP: 0000000000000004 R08: ffffffff8157ffc2 R09: fffffbfff1c39af8
> [ 8.143997][ T1] R10: dffffc0000000000 R11: fffffbfff1c39af8 R12: ffffea000502cdc0
> [ 8.143997][ T1] R13: ffffea000502cdc8 R14: 1ffffd4000a059b9 R15: 0000000000000000
> [ 8.143997][ T1] ? __warn_printk+0x292/0x360
> [ 8.143997][ T1] ? refcount_warn_saturate+0xf9/0x1d0
> [ 8.143997][ T1] __free_pages_ok+0xc60/0xd90
> [ 8.143997][ T1] make_alloc_exact+0xa3/0xf0
> [ 8.153906][ T1] vring_alloc_queue_split+0x20a/0x600
> [ 8.153906][ T1] ? __pfx_vring_alloc_queue_split+0x10/0x10
> [ 8.153906][ T1] ? vp_find_vqs+0x4c/0x4e0
> [ 8.153906][ T1] ? virtscsi_probe+0x3ea/0xf60
> [ 8.153906][ T1] ? virtio_dev_probe+0x991/0xaf0
> [ 8.153906][ T1] ? really_probe+0x2b8/0xad0
> [ 8.153906][ T1] ? driver_probe_device+0x50/0x430
> [ 8.153906][ T1] vring_create_virtqueue_split+0xc6/0x310
> [ 8.153906][ T1] ? ret_from_fork+0x4b/0x80
> [ 8.153906][ T1] ? __pfx_vring_create_virtqueue_split+0x10/0x10
> [ 8.163970][ T1] vring_create_virtqueue+0xca/0x110
> [ 8.163970][ T1] ? __pfx_vp_notify+0x10/0x10
> [ 8.163970][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.163970][ T1] setup_vq+0xe9/0x2d0
> [ 8.163970][ T1] ? __pfx_vp_notify+0x10/0x10
> [ 8.163970][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.163970][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.163970][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.173902][ T1] vp_setup_vq+0xbf/0x330
> [ 8.173902][ T1] ? __pfx_vp_config_changed+0x10/0x10
> [ 8.173902][ T1] ? ioread16+0x2f/0x90
> [ 8.173902][ T1] ? __pfx_virtscsi_ctrl_done+0x10/0x10
> [ 8.173902][ T1] vp_find_vqs_msix+0x8b2/0xc80
> [ 8.173902][ T1] vp_find_vqs+0x4c/0x4e0
> [ 8.173902][ T1] virtscsi_init+0x8db/0xd00
> [ 8.173902][ T1] ? __pfx_virtscsi_init+0x10/0x10
> [ 8.173902][ T1] ? __pfx_default_calc_sets+0x10/0x10
> [ 8.183960][ T1] ? scsi_host_alloc+0xa57/0xea0
> [ 8.183960][ T1] ? vp_get+0xfd/0x140
> [ 8.183960][ T1] virtscsi_probe+0x3ea/0xf60
> [ 8.183960][ T1] ? __pfx_virtscsi_probe+0x10/0x10
> [ 8.183960][ T1] ? kernfs_add_one+0x156/0x8b0
> [ 8.183960][ T1] ? virtio_no_restricted_mem_acc+0x9/0x10
> [ 8.183960][ T1] ? virtio_features_ok+0x10c/0x270
> [ 8.193962][ T1] virtio_dev_probe+0x991/0xaf0
> [ 8.193962][ T1] ? __pfx_virtio_dev_probe+0x10/0x10
> [ 8.193962][ T1] really_probe+0x2b8/0xad0
> [ 8.193962][ T1] __driver_probe_device+0x1a2/0x390
> [ 8.193962][ T1] driver_probe_device+0x50/0x430
> [ 8.193962][ T1] __driver_attach+0x45f/0x710
> [ 8.193962][ T1] ? __pfx___driver_attach+0x10/0x10
> [ 8.193962][ T1] bus_for_each_dev+0x239/0x2b0
> [ 8.204004][ T1] ? __pfx___driver_attach+0x10/0x10
> [ 8.204004][ T1] ? __pfx_bus_for_each_dev+0x10/0x10
> [ 8.204004][ T1] ? do_raw_spin_unlock+0x13c/0x8b0
> [ 8.204004][ T1] bus_add_driver+0x347/0x620
> [ 8.204004][ T1] driver_register+0x23a/0x320
> [ 8.204004][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
> [ 8.204004][ T1] virtio_scsi_init+0x65/0xe0
> [ 8.204004][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
> [ 8.213923][ T1] do_one_initcall+0x248/0x880
> [ 8.213923][ T1] ? __pfx_virtio_scsi_init+0x10/0x10
> [ 8.213923][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
> [ 8.213923][ T1] ? __pfx_do_one_initcall+0x10/0x10
> [ 8.213923][ T1] ? __pfx_parse_args+0x10/0x10
> [ 8.213923][ T1] ? do_initcalls+0x1c/0x80
> [ 8.213923][ T1] ? rcu_is_watching+0x15/0xb0
> [ 8.223993][ T1] do_initcall_level+0x157/0x210
> [ 8.223993][ T1] do_initcalls+0x3f/0x80
> [ 8.223993][ T1] kernel_init_freeable+0x435/0x5d0
> [ 8.223993][ T1] ? __pfx_kernel_init_freeable+0x10/0x10
> [ 8.223993][ T1] ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
> [ 8.223993][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.223993][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.233955][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.233955][ T1] kernel_init+0x1d/0x2b0
> [ 8.233955][ T1] ret_from_fork+0x4b/0x80
> [ 8.233955][ T1] ? __pfx_kernel_init+0x10/0x10
> [ 8.233955][ T1] ret_from_fork_asm+0x1a/0x30
> [ 8.233955][ T1] </TASK>
> [ 8.233955][ T1] Kernel Offset: disabled
> [ 8.233955][ T1] Rebooting in 86400 seconds..
This doesn't look related at all.
--
Jens Axboe