Re: [PATCH] selftests/mm: Specify requirement for PROC_MEM_ALWAYS_FORCE=y
From: Anshuman Khandual
Date: Thu Apr 16 2026 - 22:58:05 EST
On 17/04/26 12:10 AM, Mark Brown wrote:
> Several of the mm selftests made use of /proc/pid/mem as part of their
> operation but we do not specify this in the config fragment for them, at
> least mkdirty and ksm_functional_tests have this requirement.
>
> This has been working fine in practice since PROC_MEM_ALWAYS_FORCE was the
> default setting but commit 599bbba5a36f ("proc: make PROC_MEM_FORCE_PTRACE
> the Kconfig default") that is no longer the case, meaning that tests run
> on kernels built based on defconfigs have started having the new more
> restrictive default and failing. Add PROC_MEM_ALWAYS_FORCE to the config
> fragment for the mm selftests.
>
> Thanks to Aishwarya TCV for spotting the issue and identifying the commit
> that introduced it.
>
> Reported-by: Aishwarya TCV <aishwarya.tcv@xxxxxxx>
> Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Reviewed-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
> ---
> tools/testing/selftests/mm/config | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/tools/testing/selftests/mm/config b/tools/testing/selftests/mm/config
> index 1dbe2b4558ab..06f78bd232e2 100644
> --- a/tools/testing/selftests/mm/config
> +++ b/tools/testing/selftests/mm/config
> @@ -13,3 +13,4 @@ CONFIG_PROFILING=y
> CONFIG_UPROBES=y
> CONFIG_MEMORY_FAILURE=y
> CONFIG_HWPOISON_INJECT=m
> +CONFIG_PROC_MEM_ALWAYS_FORCE=y
>
> ---
> base-commit: 599bbba5a36f6de57ab14c373c25881e2b5273f5
> change-id: 20260416-selftests-mm-proc-mem-always-force-5ce1b26022c2
>
> Best regards,
> --
> Mark Brown <broonie@xxxxxxxxxx>
>
>