On 7/20/2021 23:43, Huang Pei wrote:
> +. According to Documentation/vm/split_page_table_lock, handle failure
> of pgtable_pmd_page_ctor
>
> +. use GFP_KERNEL_ACCOUNT instead of GFP_KERNEL|__GFP_ACCOUNT
>
> Reported-by: Joshua Kinard <kumba@xxxxxxxxxx>
> Signed-off-by: Huang Pei <huangpei@xxxxxxxxxxx>
> ---
> arch/mips/include/asm/pgalloc.h | 12 ++++++++----
> 1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/arch/mips/include/asm/pgalloc.h b/arch/mips/include/asm/pgalloc.h
> index d0cf997b4ba8..5c9597a6c60c 100644
> --- a/arch/mips/include/asm/pgalloc.h
> +++ b/arch/mips/include/asm/pgalloc.h
> @@ -62,11 +62,15 @@ static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
> pmd_t *pmd = NULL;
> struct page *pg;
>
> - pg = alloc_pages(GFP_KERNEL | __GFP_ACCOUNT, PMD_ORDER);
> + pg = alloc_pages(GFP_KERNEL_ACCOUNT, PMD_ORDER);
> if (pg) {
> - pgtable_pmd_page_ctor(pg);
> - pmd = (pmd_t *)page_address(pg);
> - pmd_init((unsigned long)pmd, (unsigned long)invalid_pte_table);
> + if(pgtable_pmd_page_ctor(pg)) {
> + pmd = (pmd_t *)page_address(pg);
> + pmd_init((unsigned long)pmd, (unsigned long)invalid_pte_table);
> + } else {
> + __free_pages(pg, PMD_ORDER);
> + }
> +
> }
> return pmd;
> }
>
Instead of the nested if statements, why not go with something that looks more
like what is in arch/x86/include/asm/pgalloc.h?
Note, I don't have a full kernel tree in front of me at the moment, so this is
just the refactored function of pmd_alloc_one:
static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
{
pmd_t *pmd;
struct page *page;
page = alloc_pages(GFP_KERNEL_ACCOUNT, PMD_ORDER);
if (!page)
return NULL;
if (!pgtable_pmd_page_ctor(page)) {
__free_pages(page, PMD_ORDER);
return NULL;
}
pmd = (pmd_t *)page_address(page);
pmd_init((unsigned long)pmd, (unsigned long)invalid_pte_table);
return pmd;
}
--
Joshua Kinard
Gentoo/MIPS
kumba@xxxxxxxxxx
rsa6144/5C63F4E3F5C6C943 2015-04-27
177C 1972 1FB8 F254 BAD0 3E72 5C63 F4E3 F5C6 C943
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