[PATCH 5.13 060/175] MIPS: check return value of pgtable_pmd_page_ctor

From: Greg Kroah-Hartman
Date: Tue Aug 10 2021 - 14:02:07 EST


From: Huang Pei <huangpei@xxxxxxxxxxx>

[ Upstream commit 6aa32467299e9e12280a6aec9dbc21bf2db830b0 ]

+. 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

+. Adjust coding style

Fixes: ed914d48b6a1 ("MIPS: add PMD table accounting into MIPS')
Reported-by: Joshua Kinard <kumba@xxxxxxxxxx>
Signed-off-by: Huang Pei <huangpei@xxxxxxxxxxx>
Reviewed-by: Joshua Kinard <kumba@xxxxxxxxxx>
Signed-off-by: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/mips/include/asm/pgalloc.h | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/mips/include/asm/pgalloc.h b/arch/mips/include/asm/pgalloc.h
index d0cf997b4ba8..139b4050259f 100644
--- a/arch/mips/include/asm/pgalloc.h
+++ b/arch/mips/include/asm/pgalloc.h
@@ -59,15 +59,20 @@ do { \

static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
{
- pmd_t *pmd = NULL;
+ pmd_t *pmd;
struct page *pg;

- pg = alloc_pages(GFP_KERNEL | __GFP_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);
+ pg = alloc_pages(GFP_KERNEL_ACCOUNT, PMD_ORDER);
+ if (!pg)
+ return NULL;
+
+ if (!pgtable_pmd_page_ctor(pg)) {
+ __free_pages(pg, PMD_ORDER);
+ return NULL;
}
+
+ pmd = (pmd_t *)page_address(pg);
+ pmd_init((unsigned long)pmd, (unsigned long)invalid_pte_table);
return pmd;
}

--
2.30.2