Re: [PATCH] mm/filemap: __filemap_add_folio() restore index before retrying

[Matthew Wilcox]

On Mon, Jul 27, 2026 at 10:24:14PM -0700, Hugh Dickins wrote:
> Production was suffering from rare SIGILLs and SIGSEGVs, executable text
> found a page away from where it belonged, !folio_contains() bug hit when
> debug enabled: symptoms not seen since this patch went in.

That can't have been fun to find.  Thanks, Hugh!

> Fixes: 200a89c159a7 ("mm/filemap: use xas_try_split() in __filemap_add_folio()")
> Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx

Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>