From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> A compound page in the page cache will not necessarily be of PMD size, so check explicitly. Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> --- mm/memory.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index f703fe8c8346..d68ce428ddd2 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3549,13 +3549,14 @@ 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 (page_order(page) != HPAGE_PMD_ORDER) + return ret; /* * Archs like ppc64 need additonal space to store information -- 2.26.2
