Re: [PATCH v1 02/27] powerpc/mm: don't BUG in add_huge_page_size()

From: Aneesh Kumar K.V
Date: Thu Apr 11 2019 - 01:41:25 EST


Christophe Leroy <christophe.leroy@xxxxxx> writes:

> No reason to BUG() in add_huge_page_size(). Just WARN and
> reject the add.
>
> Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
> ---
> arch/powerpc/mm/hugetlbpage.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
> index 9e732bb2c84a..cf2978e235f3 100644
> --- a/arch/powerpc/mm/hugetlbpage.c
> +++ b/arch/powerpc/mm/hugetlbpage.c
> @@ -634,7 +634,8 @@ static int __init add_huge_page_size(unsigned long long size)
> }
> #endif
>
> - BUG_ON(mmu_psize_defs[mmu_psize].shift != shift);
> + if (WARN_ON(mmu_psize_defs[mmu_psize].shift != shift))
> + return -EINVAL;

Same here. There are not catching runtime errors. We should never find
that true. This is to catch mistakes during development changes. Switch
to VM_BUG_ON?


>
> /* Return if huge page size has already been setup */
> if (size_to_hstate(size))
> --
> 2.13.3