From 9c245c54f59b89fa2189a88407f129959394a3e3 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Tue, 29 May 2012 15:06:14 -0700 Subject: [PATCH] pagemap.h: fix warning about possibly used before init var Commit 43046020c6cb ("mm: extend prefault helpers to fault in more than PAGE_SIZE") added in the new functions: fault_in_multipages_writeable() and fault_in_multipages_readable(). However, we currently see: include/linux/pagemap.h:492: warning: 'ret' may be used uninitialized in this function include/linux/pagemap.h:492: note: 'ret' was declared here Unlike a lot of gcc nags, this one appears somewhat legit. i.e. passing in an invalid negative value of "size" does make it look like all the conditionals in there would be bypassed and the uninitialized value would be returned. Signed-off-by: Paul Gortmaker Cc: Daniel Vetter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index efa26b4da8d2b..7cfad3bbb0cc2 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -460,11 +460,11 @@ static inline int fault_in_pages_readable(const char __user *uaddr, int size) */ static inline int fault_in_multipages_writeable(char __user *uaddr, int size) { - int ret; + int ret = 0; char __user *end = uaddr + size - 1; if (unlikely(size == 0)) - return 0; + return ret; /* * Writing zeroes into userspace here is OK, because we know that if @@ -489,11 +489,11 @@ static inline int fault_in_multipages_readable(const char __user *uaddr, int size) { volatile char c; - int ret; + int ret = 0; const char __user *end = uaddr + size - 1; if (unlikely(size == 0)) - return 0; + return ret; while (uaddr <= end) { ret = __get_user(c, uaddr); -- 2.39.5