Commit 5c91c0e7 authored by Qi Zheng's avatar Qi Zheng Committed by Linus Torvalds
Browse files

mm/memory_failure: fix the missing pte_unmap() call 

The paired pte_unmap() call is missing before the
dev_pagemap_mapping_shift() returns.  So fix it.

David says:
 "I guess this code never runs on 32bit / highmem, that's why we didn't
  notice so far".

[akpm@linux-foundation.org: cleanup]

Link: https://lkml.kernel.org/r/20210923122642.4999-1-zhengqi.arch@bytedance.com


Signed-off-by: default avatarQi Zheng <zhengqi.arch@bytedance.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 19532869

mm/memory-failure.c

+5 −5
Original line number Diff line number Diff line
@@ -306,6 +306,7 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, 
		struct vm_area_struct *vma)

{

	unsigned long address = vma_address(page, vma);

	unsigned long ret = 0;

	pgd_t *pgd;

	p4d_t *p4d;

	pud_t *pud;
@@ -329,11 +330,10 @@ static unsigned long dev_pagemap_mapping_shift(struct page *page, 
	if (pmd_devmap(*pmd))

		return PMD_SHIFT;

	pte = pte_offset_map(pmd, address);

	if (!pte_present(*pte))

		return 0;

	if (pte_devmap(*pte))

		return PAGE_SHIFT;

	return 0;

	if (pte_present(*pte) && pte_devmap(*pte))

		ret = PAGE_SHIFT;

	pte_unmap(pte);

	return ret;

}



/*