1 files changed, 2 insertions, 1 deletions

diff --git a/mm/memory.c b/mm/memory.c
index e229970e4223..1cc6bfbd872e 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -2053,7 +2053,8 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
         old_page = vm_normal_page(vma, address, orig_pte);
         if (!old_page) {
                 /*
-                 * VM_MIXEDMAP !pfn_valid() case
+                 * VM_MIXEDMAP !pfn_valid() case, or VM_SOFTDIRTY clear on a
+                 * VM_PFNMAP VMA.
                  *
                  * We should not cow pages in a shared writeable mapping.
                  * Just mark the pages writable as we can't do any dirty