mm/shmem: don't release a swapin-error marker as a swap entry

A failed shmem swapin (eg, EIO) frees the swap slot and leaves a
PTE_MARKER_POISONED entry in the page cache.  On truncate or eviction
shmem_free_swap() passes that marker to swap_put_entries_direct(), which
warns because it is not a swap entry.  There is nothing left to release
either way.

Skip the release for non-swap entries, as every other caller already does.

Link: https://lore.kernel.org/20260920155002.1030454-1-devnexen@gmail.com
Fixes: ac2d3268284b ("mm/swapfile.c: remove the unneeded checking")
Signed-off-by: David Carlier <devnexen@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reported-by: syzbot+23b25ba3c6bf971f9c57@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=23b25ba3c6bf971f9c57
Reviewed-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Cc: Baoquan he <bhe@redhat.com>
Cc: Barry Song <baohua@kernel.org>
Cc: Chis Li <chrisl@kernel.org> (Google)
Cc: Hugh Dickens <hughd@google.com>
Cc: Kairui Song <kasong@tencent.com>
Cc: Kemeng Shi <shikemeng@huaweicloud.com>
Cc: Nhat Pham <nphamcs@gmail.com>
Cc: <stable@vger.kernel.org>

0 files changed, 0 insertions, 0 deletions