2021-03-04 11:13:16

by Petr Mladek

[permalink] [raw]
Subject: drm/ttm: ttm_bo_release called without lock

Hi,

the following warning is filling my kernel log buffer
with 5.12-rc1+ kernels:

[ 941.070598] WARNING: CPU: 0 PID: 11 at drivers/gpu/drm/ttm/ttm_bo.c:139 ttm_bo_move_to_lru_tail+0x1ba/0x210
[ 941.070601] Modules linked in:
[ 941.070603] CPU: 0 PID: 11 Comm: kworker/0:1 Kdump: loaded Tainted: G W 5.12.0-rc1-default+ #81
[ 941.070605] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 941.070606] Workqueue: events qxl_gc_work
[ 941.070609] RIP: 0010:ttm_bo_move_to_lru_tail+0x1ba/0x210
[ 941.070610] Code: 93 e8 02 00 00 48 89 0a e9 00 ff ff ff 48 8b 87 38 01 00 00 be ff ff ff ff 48 8d 78 70 e8 8e 7d 46 00 85 c0 0f 85 6f fe ff ff <0f> 0b 8b 93 fc 02 00 00 85 d2 0f 84 6d fe ff ff 48 89 df 5b 5d 41
[ 941.070612] RSP: 0018:ffffbddf4008fd38 EFLAGS: 00010246
[ 941.070614] RAX: 0000000000000000 RBX: ffff95ae485bac00 RCX: 0000000000000002
[ 941.070615] RDX: 0000000000000000 RSI: ffff95ae485badb0 RDI: ffff95ae40305108
[ 941.070616] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
[ 941.070617] R10: ffffbddf4008fc10 R11: ffffffffa5401580 R12: ffff95ae42a94e90
[ 941.070618] R13: ffff95ae485bae70 R14: ffff95ae485bac00 R15: ffff95ae455d1800
[ 941.070620] FS: 0000000000000000(0000) GS:ffff95aebf600000(0000) knlGS:0000000000000000
[ 941.070621] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 941.070622] CR2: 00007f8ffb2f8000 CR3: 0000000102c5e005 CR4: 0000000000370ef0
[ 941.070624] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 941.070626] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 941.070627] Call Trace:
[ 941.070630] ttm_bo_release+0x551/0x600
[ 941.070635] qxl_bo_unref+0x3a/0x50
[ 941.070638] qxl_release_free_list+0x62/0xc0
[ 941.070643] qxl_release_free+0x76/0xe0
[ 941.070646] qxl_garbage_collect+0xd9/0x190
[ 941.080241] process_one_work+0x2b0/0x630
[ 941.080249] ? process_one_work+0x630/0x630
[ 941.080251] worker_thread+0x39/0x3f0
[ 941.080255] ? process_one_work+0x630/0x630
[ 941.080257] kthread+0x13a/0x150
[ 941.080260] ? kthread_create_worker_on_cpu+0x70/0x70
[ 941.080265] ret_from_fork+0x1f/0x30
[ 941.080277] irq event stamp: 757191
[ 941.080278] hardirqs last enabled at (757197): [<ffffffffa217431f>] vprintk_emit+0x27f/0x2c0
[ 941.080280] hardirqs last disabled at (757202): [<ffffffffa21742dc>] vprintk_emit+0x23c/0x2c0
[ 941.080281] softirqs last enabled at (755768): [<ffffffffa300030f>] __do_softirq+0x30f/0x432
[ 941.080284] softirqs last disabled at (755763): [<ffffffffa20eb0aa>] irq_exit_rcu+0xea/0xf0

My wild guess is that it might be related to the commit
3d1a88e1051f5d788d789 ("drm/ttm: cleanup LRU handling further").

Does it ring any bell, please?

Best Regards,
Petr


2021-03-04 11:35:36

by Petr Mladek

[permalink] [raw]
Subject: Re: drm/ttm: ttm_bo_release called without lock

On Wed 2021-03-03 15:34:09, Petr Mladek wrote:
> Hi,
>
> the following warning is filling my kernel log buffer
> with 5.12-rc1+ kernels:
>
> [ 941.070598] WARNING: CPU: 0 PID: 11 at drivers/gpu/drm/ttm/ttm_bo.c:139 ttm_bo_move_to_lru_tail+0x1ba/0x210
> [ 941.070601] Modules linked in:
> [ 941.070603] CPU: 0 PID: 11 Comm: kworker/0:1 Kdump: loaded Tainted: G W 5.12.0-rc1-default+ #81
> [ 941.070605] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
> [ 941.070606] Workqueue: events qxl_gc_work
> [ 941.070609] RIP: 0010:ttm_bo_move_to_lru_tail+0x1ba/0x210
> [ 941.070610] Code: 93 e8 02 00 00 48 89 0a e9 00 ff ff ff 48 8b 87 38 01 00 00 be ff ff ff ff 48 8d 78 70 e8 8e 7d 46 00 85 c0 0f 85 6f fe ff ff <0f> 0b 8b 93 fc 02 00 00 85 d2 0f 84 6d fe ff ff 48 89 df 5b 5d 41
> [ 941.070612] RSP: 0018:ffffbddf4008fd38 EFLAGS: 00010246
> [ 941.070614] RAX: 0000000000000000 RBX: ffff95ae485bac00 RCX: 0000000000000002
> [ 941.070615] RDX: 0000000000000000 RSI: ffff95ae485badb0 RDI: ffff95ae40305108
> [ 941.070616] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
> [ 941.070617] R10: ffffbddf4008fc10 R11: ffffffffa5401580 R12: ffff95ae42a94e90
> [ 941.070618] R13: ffff95ae485bae70 R14: ffff95ae485bac00 R15: ffff95ae455d1800
> [ 941.070620] FS: 0000000000000000(0000) GS:ffff95aebf600000(0000) knlGS:0000000000000000
> [ 941.070621] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 941.070622] CR2: 00007f8ffb2f8000 CR3: 0000000102c5e005 CR4: 0000000000370ef0
> [ 941.070624] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [ 941.070626] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [ 941.070627] Call Trace:
> [ 941.070630] ttm_bo_release+0x551/0x600
> [ 941.070635] qxl_bo_unref+0x3a/0x50
> [ 941.070638] qxl_release_free_list+0x62/0xc0
> [ 941.070643] qxl_release_free+0x76/0xe0
> [ 941.070646] qxl_garbage_collect+0xd9/0x190
> [ 941.080241] process_one_work+0x2b0/0x630
> [ 941.080249] ? process_one_work+0x630/0x630
> [ 941.080251] worker_thread+0x39/0x3f0
> [ 941.080255] ? process_one_work+0x630/0x630
> [ 941.080257] kthread+0x13a/0x150
> [ 941.080260] ? kthread_create_worker_on_cpu+0x70/0x70
> [ 941.080265] ret_from_fork+0x1f/0x30
> [ 941.080277] irq event stamp: 757191
> [ 941.080278] hardirqs last enabled at (757197): [<ffffffffa217431f>] vprintk_emit+0x27f/0x2c0
> [ 941.080280] hardirqs last disabled at (757202): [<ffffffffa21742dc>] vprintk_emit+0x23c/0x2c0
> [ 941.080281] softirqs last enabled at (755768): [<ffffffffa300030f>] __do_softirq+0x30f/0x432
> [ 941.080284] softirqs last disabled at (755763): [<ffffffffa20eb0aa>] irq_exit_rcu+0xea/0xf0

I have just realized that it actually prints two warnings over and
over again. The 2nd one is:

[ 186.078790] WARNING: CPU: 0 PID: 146 at drivers/gpu/drm/ttm/ttm_bo.c:512 ttm_bo_release+0x533/0x600
[ 186.078794] Modules linked in:
[ 186.078795] CPU: 0 PID: 146 Comm: kworker/0:2 Kdump: loaded Tainted: G W 5.12.0-rc1-default+ #81
[ 186.078797] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
[ 186.078799] Workqueue: events qxl_gc_work
[ 186.078801] RIP: 0010:ttm_bo_release+0x533/0x600
[ 186.078803] Code: e9 c6 fb ff ff 4c 8b 7d d0 b9 4c 1d 00 00 31 d2 be 01 00 00 00 49 8b bf d0 fe ff ff e8 86 f1 04 00 49 8b
47 e0 e9 2b ff ff ff <0f> 0b 48 8b 45 d0 31 d2 4c 89 f7 48 8d 70 08 c7 80 94 00 00 00 00
[ 186.078805] RSP: 0018:ffffa22a402e3d60 EFLAGS: 00010202
[ 186.078807] RAX: 0000000000000001 RBX: ffff9334cd8f5668 RCX: 0000000000001180
[ 186.078808] RDX: ffff93353f61a7c0 RSI: ffffffffa6401580 RDI: ffff9334c44f9588
[ 186.078810] RBP: ffffa22a402e3d90 R08: 0000000000000001 R09: 0000000000000001
[ 186.078811] R10: ffffa22a402e3c10 R11: ffffffffa6401580 R12: ffff9334c48fa300
[ 186.078812] R13: ffff9334c0f24e90 R14: ffff9334cd8f5400 R15: ffff9334c4528000
[ 186.078813] FS: 0000000000000000(0000) GS:ffff93353f600000(0000) knlGS:0000000000000000
[ 186.078814] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 186.078816] CR2: 00007f1908079860 CR3: 0000000021824004 CR4: 0000000000370ef0
[ 186.078818] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 186.078819] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 186.078821] Call Trace:
[ 186.078826] qxl_bo_unref+0x3a/0x50
[ 186.078829] qxl_release_free_list+0x62/0xc0
[ 186.078834] qxl_release_free+0x76/0xe0
[ 186.078837] qxl_garbage_collect+0xd9/0x190
[ 186.078843] process_one_work+0x2b0/0x630
[ 186.078850] ? process_one_work+0x630/0x630
[ 186.078853] worker_thread+0x39/0x3f0
[ 186.078857] ? process_one_work+0x630/0x630
[ 186.078859] kthread+0x13a/0x150
[ 186.078861] ? kthread_create_worker_on_cpu+0x70/0x70
[ 186.078866] ret_from_fork+0x1f/0x30
[ 186.078879] irq event stamp: 619687
[ 186.091417] hardirqs last enabled at (619761): [<ffffffffa317293b>] console_unlock+0x45b/0x570
[ 186.091421] hardirqs last disabled at (619766): [<ffffffffa31742dc>] vprintk_emit+0x23c/0x2c0
[ 186.091423] softirqs last enabled at (617742): [<ffffffffa400030f>] __do_softirq+0x30f/0x432
[ 186.091425] softirqs last disabled at (617737): [<ffffffffa30eb0aa>] irq_exit_rcu+0xea/0xf0
[ 186.091427] ---[ end trace ac74376b06d2036c ]---


Tke kernel is based on Linus' tree and the last commit
f69d02e37a85645aa90d1 ("Merge tag 'misc-5.12-2021-03-02' of
git://git.kernel.dk/linux-block").

Best Regards,
Petr

2021-03-04 17:20:47

by Gerd Hoffmann

[permalink] [raw]
Subject: Re: drm/ttm: ttm_bo_release called without lock

On Thu, Mar 04, 2021 at 08:42:55AM +0100, Thomas Zimmermann wrote:
> (cc'ing Gerd)
>
> This might be related to the recent clean-up patches for the BO handling in
> qxl.

Yes, it is. Fixed in drm-misc-next, cherry-picked into drm-misc-fixes,
hopefully lands in -rc2.

take care,
Gerd

2021-03-05 00:05:15

by Thomas Zimmermann

[permalink] [raw]
Subject: Re: drm/ttm: ttm_bo_release called without lock

(cc'ing Gerd)

This might be related to the recent clean-up patches for the BO handling
in qxl.

Am 03.03.21 um 16:07 schrieb Petr Mladek:
> On Wed 2021-03-03 15:34:09, Petr Mladek wrote:
>> Hi,
>>
>> the following warning is filling my kernel log buffer
>> with 5.12-rc1+ kernels:
>>
>> [ 941.070598] WARNING: CPU: 0 PID: 11 at drivers/gpu/drm/ttm/ttm_bo.c:139 ttm_bo_move_to_lru_tail+0x1ba/0x210
>> [ 941.070601] Modules linked in:
>> [ 941.070603] CPU: 0 PID: 11 Comm: kworker/0:1 Kdump: loaded Tainted: G W 5.12.0-rc1-default+ #81
>> [ 941.070605] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
>> [ 941.070606] Workqueue: events qxl_gc_work
>> [ 941.070609] RIP: 0010:ttm_bo_move_to_lru_tail+0x1ba/0x210
>> [ 941.070610] Code: 93 e8 02 00 00 48 89 0a e9 00 ff ff ff 48 8b 87 38 01 00 00 be ff ff ff ff 48 8d 78 70 e8 8e 7d 46 00 85 c0 0f 85 6f fe ff ff <0f> 0b 8b 93 fc 02 00 00 85 d2 0f 84 6d fe ff ff 48 89 df 5b 5d 41
>> [ 941.070612] RSP: 0018:ffffbddf4008fd38 EFLAGS: 00010246
>> [ 941.070614] RAX: 0000000000000000 RBX: ffff95ae485bac00 RCX: 0000000000000002
>> [ 941.070615] RDX: 0000000000000000 RSI: ffff95ae485badb0 RDI: ffff95ae40305108
>> [ 941.070616] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001
>> [ 941.070617] R10: ffffbddf4008fc10 R11: ffffffffa5401580 R12: ffff95ae42a94e90
>> [ 941.070618] R13: ffff95ae485bae70 R14: ffff95ae485bac00 R15: ffff95ae455d1800
>> [ 941.070620] FS: 0000000000000000(0000) GS:ffff95aebf600000(0000) knlGS:0000000000000000
>> [ 941.070621] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> [ 941.070622] CR2: 00007f8ffb2f8000 CR3: 0000000102c5e005 CR4: 0000000000370ef0
>> [ 941.070624] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>> [ 941.070626] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
>> [ 941.070627] Call Trace:
>> [ 941.070630] ttm_bo_release+0x551/0x600
>> [ 941.070635] qxl_bo_unref+0x3a/0x50
>> [ 941.070638] qxl_release_free_list+0x62/0xc0
>> [ 941.070643] qxl_release_free+0x76/0xe0
>> [ 941.070646] qxl_garbage_collect+0xd9/0x190
>> [ 941.080241] process_one_work+0x2b0/0x630
>> [ 941.080249] ? process_one_work+0x630/0x630
>> [ 941.080251] worker_thread+0x39/0x3f0
>> [ 941.080255] ? process_one_work+0x630/0x630
>> [ 941.080257] kthread+0x13a/0x150
>> [ 941.080260] ? kthread_create_worker_on_cpu+0x70/0x70
>> [ 941.080265] ret_from_fork+0x1f/0x30
>> [ 941.080277] irq event stamp: 757191
>> [ 941.080278] hardirqs last enabled at (757197): [<ffffffffa217431f>] vprintk_emit+0x27f/0x2c0
>> [ 941.080280] hardirqs last disabled at (757202): [<ffffffffa21742dc>] vprintk_emit+0x23c/0x2c0
>> [ 941.080281] softirqs last enabled at (755768): [<ffffffffa300030f>] __do_softirq+0x30f/0x432
>> [ 941.080284] softirqs last disabled at (755763): [<ffffffffa20eb0aa>] irq_exit_rcu+0xea/0xf0
>
> I have just realized that it actually prints two warnings over and
> over again. The 2nd one is:
>
> [ 186.078790] WARNING: CPU: 0 PID: 146 at drivers/gpu/drm/ttm/ttm_bo.c:512 ttm_bo_release+0x533/0x600
> [ 186.078794] Modules linked in:
> [ 186.078795] CPU: 0 PID: 146 Comm: kworker/0:2 Kdump: loaded Tainted: G W 5.12.0-rc1-default+ #81
> [ 186.078797] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
> [ 186.078799] Workqueue: events qxl_gc_work
> [ 186.078801] RIP: 0010:ttm_bo_release+0x533/0x600
> [ 186.078803] Code: e9 c6 fb ff ff 4c 8b 7d d0 b9 4c 1d 00 00 31 d2 be 01 00 00 00 49 8b bf d0 fe ff ff e8 86 f1 04 00 49 8b
> 47 e0 e9 2b ff ff ff <0f> 0b 48 8b 45 d0 31 d2 4c 89 f7 48 8d 70 08 c7 80 94 00 00 00 00
> [ 186.078805] RSP: 0018:ffffa22a402e3d60 EFLAGS: 00010202
> [ 186.078807] RAX: 0000000000000001 RBX: ffff9334cd8f5668 RCX: 0000000000001180
> [ 186.078808] RDX: ffff93353f61a7c0 RSI: ffffffffa6401580 RDI: ffff9334c44f9588
> [ 186.078810] RBP: ffffa22a402e3d90 R08: 0000000000000001 R09: 0000000000000001
> [ 186.078811] R10: ffffa22a402e3c10 R11: ffffffffa6401580 R12: ffff9334c48fa300
> [ 186.078812] R13: ffff9334c0f24e90 R14: ffff9334cd8f5400 R15: ffff9334c4528000
> [ 186.078813] FS: 0000000000000000(0000) GS:ffff93353f600000(0000) knlGS:0000000000000000
> [ 186.078814] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [ 186.078816] CR2: 00007f1908079860 CR3: 0000000021824004 CR4: 0000000000370ef0
> [ 186.078818] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
> [ 186.078819] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
> [ 186.078821] Call Trace:
> [ 186.078826] qxl_bo_unref+0x3a/0x50
> [ 186.078829] qxl_release_free_list+0x62/0xc0
> [ 186.078834] qxl_release_free+0x76/0xe0
> [ 186.078837] qxl_garbage_collect+0xd9/0x190
> [ 186.078843] process_one_work+0x2b0/0x630
> [ 186.078850] ? process_one_work+0x630/0x630
> [ 186.078853] worker_thread+0x39/0x3f0
> [ 186.078857] ? process_one_work+0x630/0x630
> [ 186.078859] kthread+0x13a/0x150
> [ 186.078861] ? kthread_create_worker_on_cpu+0x70/0x70
> [ 186.078866] ret_from_fork+0x1f/0x30
> [ 186.078879] irq event stamp: 619687
> [ 186.091417] hardirqs last enabled at (619761): [<ffffffffa317293b>] console_unlock+0x45b/0x570
> [ 186.091421] hardirqs last disabled at (619766): [<ffffffffa31742dc>] vprintk_emit+0x23c/0x2c0
> [ 186.091423] softirqs last enabled at (617742): [<ffffffffa400030f>] __do_softirq+0x30f/0x432
> [ 186.091425] softirqs last disabled at (617737): [<ffffffffa30eb0aa>] irq_exit_rcu+0xea/0xf0
> [ 186.091427] ---[ end trace ac74376b06d2036c ]---
>
>
> Tke kernel is based on Linus' tree and the last commit
> f69d02e37a85645aa90d1 ("Merge tag 'misc-5.12-2021-03-02' of
> git://git.kernel.dk/linux-block").
>
> Best Regards,
> Petr
> _______________________________________________
> dri-devel mailing list
> [email protected]
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>

--
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Felix Imendörffer


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2021-03-05 00:05:22

by Christian König

[permalink] [raw]
Subject: Re: drm/ttm: ttm_bo_release called without lock

I also already send a patch to the list to mitigate the warnings into a
WARN_ON_ONCE().

Christian.

Am 04.03.21 um 08:42 schrieb Thomas Zimmermann:
> (cc'ing Gerd)
>
> This might be related to the recent clean-up patches for the BO
> handling in qxl.
>
> Am 03.03.21 um 16:07 schrieb Petr Mladek:
>> On Wed 2021-03-03 15:34:09, Petr Mladek wrote:
>>> Hi,
>>>
>>> the following warning is filling my kernel log buffer
>>> with 5.12-rc1+ kernels:
>>>
>>> [  941.070598] WARNING: CPU: 0 PID: 11 at
>>> drivers/gpu/drm/ttm/ttm_bo.c:139 ttm_bo_move_to_lru_tail+0x1ba/0x210
>>> [  941.070601] Modules linked in:
>>> [  941.070603] CPU: 0 PID: 11 Comm: kworker/0:1 Kdump: loaded
>>> Tainted: G        W         5.12.0-rc1-default+ #81
>>> [  941.070605] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009),
>>> BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
>>> [  941.070606] Workqueue: events qxl_gc_work
>>> [  941.070609] RIP: 0010:ttm_bo_move_to_lru_tail+0x1ba/0x210
>>> [  941.070610] Code: 93 e8 02 00 00 48 89 0a e9 00 ff ff ff 48 8b 87
>>> 38 01 00 00 be ff ff ff ff 48 8d 78 70 e8 8e 7d 46 00 85 c0 0f 85 6f
>>> fe ff ff <0f> 0b 8b 93 fc 02 00 00 85 d2 0f 84 6d fe ff ff 48 89 df
>>> 5b 5d 41
>>> [  941.070612] RSP: 0018:ffffbddf4008fd38 EFLAGS: 00010246
>>> [  941.070614] RAX: 0000000000000000 RBX: ffff95ae485bac00 RCX:
>>> 0000000000000002
>>> [  941.070615] RDX: 0000000000000000 RSI: ffff95ae485badb0 RDI:
>>> ffff95ae40305108
>>> [  941.070616] RBP: 0000000000000000 R08: 0000000000000001 R09:
>>> 0000000000000001
>>> [  941.070617] R10: ffffbddf4008fc10 R11: ffffffffa5401580 R12:
>>> ffff95ae42a94e90
>>> [  941.070618] R13: ffff95ae485bae70 R14: ffff95ae485bac00 R15:
>>> ffff95ae455d1800
>>> [  941.070620] FS:  0000000000000000(0000) GS:ffff95aebf600000(0000)
>>> knlGS:0000000000000000
>>> [  941.070621] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>>> [  941.070622] CR2: 00007f8ffb2f8000 CR3: 0000000102c5e005 CR4:
>>> 0000000000370ef0
>>> [  941.070624] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
>>> 0000000000000000
>>> [  941.070626] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
>>> 0000000000000400
>>> [  941.070627] Call Trace:
>>> [  941.070630]  ttm_bo_release+0x551/0x600
>>> [  941.070635]  qxl_bo_unref+0x3a/0x50
>>> [  941.070638]  qxl_release_free_list+0x62/0xc0
>>> [  941.070643]  qxl_release_free+0x76/0xe0
>>> [  941.070646]  qxl_garbage_collect+0xd9/0x190
>>> [  941.080241]  process_one_work+0x2b0/0x630
>>> [  941.080249]  ? process_one_work+0x630/0x630
>>> [  941.080251]  worker_thread+0x39/0x3f0
>>> [  941.080255]  ? process_one_work+0x630/0x630
>>> [  941.080257]  kthread+0x13a/0x150
>>> [  941.080260]  ? kthread_create_worker_on_cpu+0x70/0x70
>>> [  941.080265]  ret_from_fork+0x1f/0x30
>>> [  941.080277] irq event stamp: 757191
>>> [  941.080278] hardirqs last  enabled at (757197):
>>> [<ffffffffa217431f>] vprintk_emit+0x27f/0x2c0
>>> [  941.080280] hardirqs last disabled at (757202):
>>> [<ffffffffa21742dc>] vprintk_emit+0x23c/0x2c0
>>> [  941.080281] softirqs last  enabled at (755768):
>>> [<ffffffffa300030f>] __do_softirq+0x30f/0x432
>>> [  941.080284] softirqs last disabled at (755763):
>>> [<ffffffffa20eb0aa>] irq_exit_rcu+0xea/0xf0
>>
>> I have just realized that it actually prints two warnings over and
>> over again. The 2nd one is:
>>
>> [  186.078790] WARNING: CPU: 0 PID: 146 at
>> drivers/gpu/drm/ttm/ttm_bo.c:512 ttm_bo_release+0x533/0x600
>> [  186.078794] Modules linked in:
>> [  186.078795] CPU: 0 PID: 146 Comm: kworker/0:2 Kdump: loaded
>> Tainted: G        W         5.12.0-rc1-default+ #81
>> [  186.078797] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009),
>> BIOS rel-1.12.0-59-gc9ba527-rebuilt.opensuse.org 04/01/2014
>> [  186.078799] Workqueue: events qxl_gc_work
>> [  186.078801] RIP: 0010:ttm_bo_release+0x533/0x600
>> [  186.078803] Code: e9 c6 fb ff ff 4c 8b 7d d0 b9 4c 1d 00 00 31 d2
>> be 01 00 00 00 49 8b bf d0 fe ff ff e8 86 f1 04 00 49 8b
>> 47 e0 e9 2b ff ff ff <0f> 0b 48 8b 45 d0 31 d2 4c 89 f7 48 8d 70 08
>> c7 80 94 00 00 00 00
>> [  186.078805] RSP: 0018:ffffa22a402e3d60 EFLAGS: 00010202
>> [  186.078807] RAX: 0000000000000001 RBX: ffff9334cd8f5668 RCX:
>> 0000000000001180
>> [  186.078808] RDX: ffff93353f61a7c0 RSI: ffffffffa6401580 RDI:
>> ffff9334c44f9588
>> [  186.078810] RBP: ffffa22a402e3d90 R08: 0000000000000001 R09:
>> 0000000000000001
>> [  186.078811] R10: ffffa22a402e3c10 R11: ffffffffa6401580 R12:
>> ffff9334c48fa300
>> [  186.078812] R13: ffff9334c0f24e90 R14: ffff9334cd8f5400 R15:
>> ffff9334c4528000
>> [  186.078813] FS:  0000000000000000(0000) GS:ffff93353f600000(0000)
>> knlGS:0000000000000000
>> [  186.078814] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>> [  186.078816] CR2: 00007f1908079860 CR3: 0000000021824004 CR4:
>> 0000000000370ef0
>> [  186.078818] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
>> 0000000000000000
>> [  186.078819] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
>> 0000000000000400
>> [  186.078821] Call Trace:
>> [  186.078826]  qxl_bo_unref+0x3a/0x50
>> [  186.078829]  qxl_release_free_list+0x62/0xc0
>> [  186.078834]  qxl_release_free+0x76/0xe0
>> [  186.078837]  qxl_garbage_collect+0xd9/0x190
>> [  186.078843]  process_one_work+0x2b0/0x630
>> [  186.078850]  ? process_one_work+0x630/0x630
>> [  186.078853]  worker_thread+0x39/0x3f0
>> [  186.078857]  ? process_one_work+0x630/0x630
>> [  186.078859]  kthread+0x13a/0x150
>> [  186.078861]  ? kthread_create_worker_on_cpu+0x70/0x70
>> [  186.078866]  ret_from_fork+0x1f/0x30
>> [  186.078879] irq event stamp: 619687
>> [  186.091417] hardirqs last  enabled at (619761):
>> [<ffffffffa317293b>] console_unlock+0x45b/0x570
>> [  186.091421] hardirqs last disabled at (619766):
>> [<ffffffffa31742dc>] vprintk_emit+0x23c/0x2c0
>> [  186.091423] softirqs last  enabled at (617742):
>> [<ffffffffa400030f>] __do_softirq+0x30f/0x432
>> [  186.091425] softirqs last disabled at (617737):
>> [<ffffffffa30eb0aa>] irq_exit_rcu+0xea/0xf0
>> [  186.091427] ---[ end trace ac74376b06d2036c ]---
>>
>>
>> Tke kernel is based on Linus' tree and the last commit
>> f69d02e37a85645aa90d1 ("Merge tag 'misc-5.12-2021-03-02' of
>> git://git.kernel.dk/linux-block").
>>
>> Best Regards,
>> Petr
>> _______________________________________________
>> dri-devel mailing list
>> [email protected]
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>>
>