[Regression] CPU stalls and eventually causes a complete system freeze with 6.0.3 due to "video/aperture: Disable and unregister sysfb devices via aperture helpers"

[Thomas Zimmermann]

Hi

Am 25.10.22 um 10:45 schrieb Andreas Thalhammer:
[...]
>> Yeah, it's also part of a larger changeset. But I wouldn't want to
>> backport all those changes either.
>>
>> Attached is a simple patch for linux-stable that adds the necessary fix.
>> If this still doesn't work, we should probably revert the problematic
>> patch.
>>
>> Please test the patch and let me know if it works.
> 
> 
> Yes, this fixed the problem. I'm running 6.0.3 with your patch now, all
> fine.

Thanks a lot for testing. If Greg doesn't already pick up the patch from 
this discussion, I'll send it to stable soonish; adding your Tested-by tag.

Best regards
Thomas

> 
> Thanks!
> Andreas
> 
>>
>> Best regards
>> Thomas
>>
>>>
>>> I don't use git and I don't know how to /cherry-pick commit/
>>> 9d69ef183815, but I found the patch here:
>>> https://patchwork.freedesktop.org/patch/494609/
>>>
>>> I hope that's the right one. I reintegrated
>>> v2-07-11-video-aperture-Disable-and-unregister-sysfb-devices-via-aperture-helpers.patch
>>> and also applied
>>> v2-04-11-fbdev-core-Remove-remove_conflicting_pci_framebuffers.patch,
>>> did a "make mrproper" and thereafter compiled a clean new 6.0.3 kernel
>>> (same .config).
>>>
>>> Now the system doesn't even boot to a console. The first boot got me to
>>> a rcu_shed stall on CPUs/tasks, same as above, but this time with:
>>> Workqueue: btrfs-cache btrfs_work_helper
>>>
>>> I booted a second time with the same kernel, and it got stuck after
>>> mounting the root btrfs filesystem (what looked like a total freeze, but
>>> when it didn't show a rcu_stall message after ~2 min I got impatient and
>>> wanted to see if I had just busted my root filesystem...)
>>>
>>> I booted 6.0.2 and everything is fine. (I'm very glad! I definitely
>>> should update my backup right away!)
>>>
>>> I will try 6.1-rc1 next, bear with...
>>>
>>
> 

-- 
Thomas Zimmermann
Graphics Driver Developer
SUSE Software Solutions Germany GmbH
Maxfeldstr. 5, 90409 Nürnberg, Germany
(HRB 36809, AG Nürnberg)
Geschäftsführer: Ivo Totev
-------------- next part --------------
A non-text attachment was scrubbed...
Name: OpenPGP_signature
Type: application/pgp-signature
Size: 840 bytes
Desc: OpenPGP digital signature
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20221025/87dc0284/attachment-0001.sig>