linux-kernel - Re: build failure from drm/ttm commit now in mainline (was: linux-next: build failure after merge of the drm tree)

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Thu, 27 Apr 2023 09:27:15 +1000
From:   Michael Ellerman <mpe@...erman.id.au>
To:     Thorsten Leemhuis <regressions@...mhuis.info>,
        Dave Airlie <airlied@...hat.com>,
        DRI <dri-devel@...ts.freedesktop.org>
Cc:     Thomas Hellström 
        <thomas.hellstrom@...ux.intel.com>,
        Christian König <christian.koenig@....com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Linux Next Mailing List <linux-next@...r.kernel.org>,
        Linux kernel regressions list <regressions@...ts.linux.dev>,
        Justin Forbes <jforbes@...hat.com>,
        Stephen Rothwell <sfr@...b.auug.org.au>
Subject: Re: build failure from drm/ttm commit now in mainline (was:
 linux-next: build failure after merge of the drm tree)

Thorsten Leemhuis <regressions@...mhuis.info> writes:
> Lo!
>
> Sometimes the regression tracker runs into regressions himself... :-D
>
> On 11.04.23 08:47, Stephen Rothwell wrote:
>> 
>> After merging the drm tree, today's linux-next build (powerpc
>> allyesconfig) failed like this:
>> 
>> drivers/gpu/drm/ttm/ttm_pool.c:73:29: error: variably modified 'global_write_combined' at file scope
>>    73 | static struct ttm_pool_type global_write_combined[TTM_DIM_ORDER];
>>       |                             ^~~~~~~~~~~~~~~~~~~~~
>> drivers/gpu/drm/ttm/ttm_pool.c:74:29: error: variably modified 'global_uncached' at file scope
>>    74 | static struct ttm_pool_type global_uncached[TTM_DIM_ORDER];
>>       |                             ^~~~~~~~~~~~~~~
>> drivers/gpu/drm/ttm/ttm_pool.c:76:29: error: variably modified 'global_dma32_write_combined' at file scope
>>    76 | static struct ttm_pool_type global_dma32_write_combined[TTM_DIM_ORDER];
>>       |                             ^~~~~~~~~~~~~~~~~~~~~~~~~~~
>> drivers/gpu/drm/ttm/ttm_pool.c:77:29: error: variably modified 'global_dma32_uncached' at file scope
>>    77 | static struct ttm_pool_type global_dma32_uncached[TTM_DIM_ORDER];
>>       |                             ^~~~~~~~~~~~~~~~~~~~~
>> 
>> Caused by commit
>> 
>>   322458c2bb1a ("drm/ttm: Reduce the number of used allocation orders for TTM pages")
>> 
>> PMD_SHIFT is not necessarily a constant on ppc (see
>> arch/powerpc/include/asm/book3s/64/pgtable.h).
>> 
>> I have reverted that commit for today.
>
> Did anyone look into this?

Christian sent a revert:
  56e51681246e ("drm/ttm: revert "Reduce the number of used allocation orders for TTM pages"")

Which has been in linux-next since the 21st. But I guess it missed being
in the initial DRM pull request.

See also other thread:
  https://lore.kernel.org/all/ZEljCgVFnDl%2FC+l3@debian/

Where Christian says the revert is "on the way" to Linus.

cheers