More to do, but its a beginning.
diff -urpN --exclude-from=/home/davej/.exclude bk-linus/mm/page-writeback.c linux-2.5/mm/page-writeback.c
--- bk-linus/mm/page-writeback.c 2003-06-30 14:01:04.000000000 +0100
+++ linux-2.5/mm/page-writeback.c 2003-07-13 16:55:51.000000000 +0100
@@ -345,7 +345,7 @@ static void wb_kupdate(unsigned long arg
* sysctl handler for /proc/sys/vm/dirty_writeback_centisecs
*/
int dirty_writeback_centisecs_handler(ctl_table *table, int write,
- struct file *file, void *buffer, size_t *length)
+ struct file *file, void __user *buffer, size_t *length)
{
proc_dointvec(table, write, file, buffer, length);
if (dirty_writeback_centisecs) {