From 52062fbca756b5fb0d8ce453a38b311354287f9d Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@g5.osdl.org>
Date: Tue, 29 Nov 2005 14:07:55 -0800
Subject: [PATCH] --- yaml --- r: 14776 b: refs/heads/master c:
 5d2a2dbbc1025dbf7998b9289574d9592b8f21cc h: refs/heads/master v: v3

---
 [refs]            |  2 +-
 trunk/mm/memory.c | 11 +++++++++--
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 5d7c7c870aad..095e83b1ffb5 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: c9cfcddfd65735437a4cb8563d6b66a6da8a5ed6
+refs/heads/master: 5d2a2dbbc1025dbf7998b9289574d9592b8f21cc
diff --git a/trunk/mm/memory.c b/trunk/mm/memory.c
index 74f95ae0510b..745b3482e6c2 100644
--- a/trunk/mm/memory.c
+++ b/trunk/mm/memory.c
@@ -1394,8 +1394,15 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
 	 */
 	if (unlikely(!src)) {
 		void *kaddr = kmap_atomic(dst, KM_USER0);
-		unsigned long left = __copy_from_user_inatomic(kaddr, (void __user *)va, PAGE_SIZE);
-		if (left)
+		void __user *uaddr = (void __user *)(va & PAGE_MASK);
+
+		/*
+		 * This really shouldn't fail, because the page is there
+		 * in the page tables. But it might just be unreadable,
+		 * in which case we just give up and fill the result with
+		 * zeroes.
+		 */
+		if (__copy_from_user_inatomic(kaddr, uaddr, PAGE_SIZE))
 			memset(kaddr, 0, PAGE_SIZE);
 		kunmap_atomic(kaddr, KM_USER0);
 		return;