Commit d01ac3c3 authored Oct 15, 2020 by Matthew Wilcox (Oracle) Committed by Linus Torvalds Oct 16, 2020

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>

parent 887b22c6

mm/memory.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -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

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