Re: [BUG][REGRESSION] mangled display since -rc1

From: Martin Kepplinger
Date: Sun Nov 06 2016 - 06:43:53 EST


Am 2016-11-06 um 12:21 schrieb Thorsten Leemhuis:
> On 01.11.2016 12:47, Jani Nikula wrote:
>> On Tue, 01 Nov 2016, Martin Kepplinger <martink@xxxxxxxxx> wrote:
>>> I'll come up with a nouveau system example and it was quite easy to bisect. To quote the merge commit msg:
>>> This also required some changes outside of the IOMMU code, but these are acked by the respective maintainers.
>>> Any help on bisecting into it would be awesome.
>> So the information here is pretty scarce. Please file a bug at [1],
>> describe the problem, perhaps add drm.debug=14 module parameter and
>> attach dmesg from boot to reproducing the problem.
>
> Martin, did you do that and can point me to the bug? And if not: Any
> news on the issue?
>
> FWIW: I added this report to the list of regressions for Linux 4.9. I'll
> watch this thread for further updates on this issue to document progress
> in my weekly reports. Please let me know via regressions@xxxxxxxxxxxxx
> in case the discussion moves to a different place (bugzilla or another
> mail thread for example).
>
> tia! Ciao, Thorsten
>

I did not file a bug in bugzilla yet. I haven't given up that we can fix
this here before the release. I've ignored it the last few days though.

Again: This is the first bad commit:

[56e520c7a0a490b63b042b047ec9659fc08762a4] Merge tag
'iommu-updates-v4.9' of
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu

If you know how to bisect into this, please share your thoughts. Linus'
merge here is bigger than iommu-update-v4.9 i think and that's what I
have to look at really. I'm not sure how though.

One part of the merge is indeed iiommu-updates-v4.9:

That's the tag:
https://git.kernel.org/cgit/linux/kernel/git/joro/iommu.git/tag/?h=iommu-updates-v4.9

and the tagged object:
https://git.kernel.org/cgit/linux/kernel/git/joro/iommu.git/commit/?h=iommu-updates-v4.9&id=13a08259187c5cd3f63d98efa159ab42976d85a4

I'll have to think about how to check the iommu-updates-v4.9 part of the
merge again... to eliminate something.