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? I today ran into what looks like the same
compiler error when building a mainline snapshot using a Fedora rawhide
config for ppc64le:
```
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];
| ^~~~~~~~~~~~~~~~~~~~~
```
Full build log:
https://copr-be.cloud.fedoraproject.org/results/@kernel-vanilla/mainline/fedora-37-ppc64le/05850588-mainline-mainline-releases/build.log.gz
Ciao, Thorsten
