On Thu, Feb 16, 2012 at 09:32:08PM +0800, Hillf Danton wrote:

On Thu, Feb 16, 2012 at 8:01 PM, Daniel Vetter [off-list ref] wrote:

quoted

@@ -416,17 +417,20 @@ static inline int fault_in_pages_writeable(char __user *uaddr, int size)
        * Writing zeroes into userspace here is OK, because we know that if
        * the zero gets there, we'll be overwriting it.
        */
-       ret = __put_user(0, uaddr);
+       while (uaddr <= end) {
+               ret = __put_user(0, uaddr);
+               if (ret != 0)
+                       return ret;
+               uaddr += PAGE_SIZE;
+       }

What if
             uaddr & ~PAGE_MASK == PAGE_SIZE -3 &&
                end & ~PAGE_MASK == 2

I don't quite follow - can you elaborate upon which issue you're seeing?
-Daniel
-- 
Daniel Vetter
Mail: daniel@ffwll.ch
Mobile: +41 (0)79 365 57 48

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>