From: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> commit d77b90d2b2642655b5f60953c36ad887257e1802 upstream. The 'shmem_falloc->nr_unswapped' is used to record how many writepage refused to swap out because fallocate() is allocating, but after shmem supports large folio swap out, the update of 'shmem_falloc->nr_unswapped' does not use the correct number of pages in the large folio, which may lead to fallocate() not exiting as soon as possible. Anyway, this is found through code inspection, and I am not sure whether it would actually cause serious issues. Link: https://lkml.kernel.org/r/f66a0119d0564c2c37c84f045835b870d1b2196f.1734593154.git.baolin.wang@xxxxxxxxxxxxxxxxx Fixes: 809bc86517cc ("mm: shmem: support large folio swap out") Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> Acked-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Hugh Dickins <hughd@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/shmem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1527,7 +1527,7 @@ try_split: !shmem_falloc->waitq && index >= shmem_falloc->start && index < shmem_falloc->next) - shmem_falloc->nr_unswapped++; + shmem_falloc->nr_unswapped += nr_pages; else shmem_falloc = NULL; spin_unlock(&inode->i_lock); Patches currently in stable-queue which might be from baolin.wang@xxxxxxxxxxxxxxxxx are queue-6.12/mm-shmem-fix-the-update-of-shmem_falloc-nr_unswapped.patch queue-6.12/mm-shmem-fix-incorrect-index-alignment-for-within_size-policy.patch
