On Fri, Apr 08, 2022 at 09:00:01PM +0900, Paran Lee wrote:
> +++ b/fs/fs-writeback.c
> @@ -1357,12 +1357,14 @@ static int move_expired_inodes(struct list_head *delaying_queue,
> LIST_HEAD(tmp);
> struct list_head *pos, *node;
> struct super_block *sb = NULL;
> - struct inode *inode;
> + struct inode *inode = NULL;
Not needed; in fact I would move the definition of inode to inside the
while loop.
> int do_sb_sort = 0;
> int moved = 0;
>
> while (!list_empty(delaying_queue)) {
> inode = wb_inode(delaying_queue->prev);
> + if (!inode)
> + continue;
Did you look at the definition of wb_inode? It can't possibly return a
NULL pointer.
> /* Move inodes from one superblock together */
> while (!list_empty(&tmp)) {
> - sb = wb_inode(tmp.prev)->i_sb;
> + inode = wb_inode(tmp.prev);
> + if (!inode)
> + continue;
> + sb = inode->i_sb;
> + if (!sb)
> + continue;
Can you explain how inode might have a NULL i_sb?
