Re: [PATCH 08/14] zram: check that backends array has at least one backend

[Andrew Morton]

On Sat, 4 May 2024 16:14:16 +0900 Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx> wrote:

> On (24/05/04 14:54), kernel test robot wrote:
> >          |                            ~~~~~~~~~~~~~~~~~~~~~~
> > >> drivers/block/zram/zcomp.c:214:2: error: call to '__compiletime_assert_285' declared with 'error' attribute: BUILD_BUG_ON failed: ARRAY_SIZE(backends) <= 1
> >      214 |         BUILD_BUG_ON(ARRAY_SIZE(backends) <= 1);
> >          |         ^
> 
> So this is what that BUILD_BUG_ON() is supposed to catch. You don't
> have any backends selected in your .config:
> 
> # CONFIG_ZRAM_BACKEND_LZO is not set
> # CONFIG_ZRAM_BACKEND_LZ4 is not set
> # CONFIG_ZRAM_BACKEND_LZ4HC is not set
> # CONFIG_ZRAM_BACKEND_ZSTD is not set
> # CONFIG_ZRAM_BACKEND_DEFLATE is not set
> CONFIG_ZRAM_DEF_COMP="unset-value"
> 
> Which is invalid configuration because it means that zram has no
> compression enabled.

We don't want s390 defconfig to be doing this!

I guess just pick one if none were selected.