2021-11-09 22:34 GMT+09:00, Matthew Wilcox <willy@xxxxxxxxxxxxx>:
> On Tue, Nov 09, 2021 at 07:45:47PM +0900, Namjae Jeon wrote:
>> Hi Matthew,
>>
>> This patch is hitting BUG_ON trap in read_pages() when running
>> xfstests for cifs.
>> There seems to be a same issue with other filesystems using .readpages ?
>
> The real fix, of course, is to migrate away from using ->readpages ;-)
> I think both 9p and nfs are going away this cycle. CIFS really needs
> to move to using the netfs interfaces.
Okay.
>
>> Could you please take a look ?
>
> Please try this patch:
Work fine.
>
> While free_unref_page_list() puts pages onto the CPU local LRU list, it
> does not remove them from the list they were passed in on. That makes
> the list_head appear to be non-empty, and would lead to various corruption
> problems if we didn't have an assertion that the list was empty.
>
> Reinitialise the list after calling free_unref_page_list() to avoid
> this problem.
>
> Fixes: 988c69f1bc23 ("mm: optimise put_pages_list()")
> Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
Tested-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Thanks!
>
> diff --git a/mm/swap.c b/mm/swap.c
> index 1841c24682f8..e8c9dc6d0377 100644
> --- a/mm/swap.c
> +++ b/mm/swap.c
> @@ -156,6 +156,7 @@ void put_pages_list(struct list_head *pages)
> }
>
> free_unref_page_list(pages);
> + INIT_LIST_HEAD(pages);
> }
> EXPORT_SYMBOL(put_pages_list);
>
>
