On Mon, Jun 30, 2014 at 02:08:11PM -0700, Hugh Dickins wrote:
> Under shmem swapping load, I sometimes hit the VM_BUG_ON_PAGE(!PageLRU)
> in isolate_lru_pages() at mm/vmscan.c:1281!
>
> Commit 2457aec63745 ("mm: non-atomically mark page accessed during page
> cache allocation where possible") looks like interrupted work-in-progress.
>
> mm/filemap.c's call to init_page_accessed() is fine, but not mm/shmem.c's
> - shmem_write_begin() is clearly wrong to use it after shmem_getpage(),
> when the page is always visible in radix_tree, and often already on LRU.
>
> Revert change to shmem_write_begin(), and use init_page_accessed() or
> mark_page_accessed() appropriately for SGP_WRITE in shmem_getpage_gfp().
>
> SGP_WRITE also covers shmem_symlink(), which did not mark_page_accessed()
> before; but since many other filesystems use [__]page_symlink(), which did
> and does mark the page accessed, consider this as rectifying an oversight.
>
> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
Acked-by: Mel Gorman <mgorman@xxxxxxx>
--
Mel Gorman
SUSE Labs
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>