mm/memory: remove page fault assumption of compound page size

A compound page in the page cache will not necessarily be of PMD size,
so check explicitly.

[willy@infradead.org: fix remove page fault assumption of compound page size]
  Link: https://lkml.kernel.org/r/20201001152259.14932-1-willy@infradead.org

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Link: https://lkml.kernel.org/r/20200908195539.25896-3-willy@infradead.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2020-10-15 20:05:26 -07:00 committed by Linus Torvalds
parent 887b22c628
commit d01ac3c352
1 changed files with 4 additions and 3 deletions

View File

@ -3709,13 +3709,14 @@ static vm_fault_t do_set_pmd(struct vm_fault *vmf, struct page *page)
unsigned long haddr = vmf->address & HPAGE_PMD_MASK;
pmd_t entry;
int i;
vm_fault_t ret;
vm_fault_t ret = VM_FAULT_FALLBACK;
if (!transhuge_vma_suitable(vma, haddr))
return VM_FAULT_FALLBACK;
return ret;
ret = VM_FAULT_FALLBACK;
page = compound_head(page);
if (compound_order(page) != HPAGE_PMD_ORDER)
return ret;
/*
* Archs like ppc64 need additonal space to store information