[PATCH] NFS: Fix oops in nfs_cancel_commit_list

Fix two bugs:
 - nfs_inode_remove_request will call nfs_clear_request, so we cannot
   reference req->wb_page after it. Move the call to dec_zone_page_state so
   that it occurs while req->wb_page is still valid.
 - Calling nfs_clear_page_writeback is unnecessary since the radix tree
   tags will have been cleared by the call to nfs_inode_remove_request.
   Replace with a simple call to nfs_unlock_request.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index ca92ac3..883dd4a 100644 (file)
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -590,10 +590,10 @@ static void nfs_cancel_commit_list(struct list_head *head)
 
        while(!list_empty(head)) {
                req = nfs_list_entry(head->next);
+               dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
                nfs_list_remove_request(req);
                nfs_inode_remove_request(req);
-               dec_zone_page_state(req->wb_page, NR_UNSTABLE_NFS);
-               nfs_clear_page_writeback(req);
+               nfs_unlock_request(req);
        }
 }