1 files changed, 7 insertions, 2 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 072139579d89..4ad2d293ddc2 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1537,10 +1537,15 @@ static vm_fault_t insert_pfn(struct vm_area_struct *vma, unsigned long addr,
                          * in may not match the PFN we have mapped if the
                          * mapped PFN is a writeable COW page.  In the mkwrite
                          * case we are creating a writable PTE for a shared
-                         * mapping and we expect the PFNs to match.
+                         * mapping and we expect the PFNs to match. If they
+                         * don't match, we are likely racing with block
+                         * allocation and mapping invalidation so just skip the
+                         * update.
                          */
-                        if (WARN_ON_ONCE(pte_pfn(*pte) != pfn_t_to_pfn(pfn)))
+                        if (pte_pfn(*pte) != pfn_t_to_pfn(pfn)) {
+                                WARN_ON_ONCE(!is_zero_pfn(pte_pfn(*pte)));
                                 goto out_unlock;
+                        }
                         entry = *pte;
                         goto out_mkwrite;
                 } else