[Devel] [PATCH VZ10] fs/fuse: remove the WARN_ON_ONCE() in fuse_revoke_readpages()

[Alexey Kuznetsov]

Ack

On Wed, Jul 1, 2026 at 2:41 PM Liu Kui <kui.liu at virtuozzo.com> wrote:
>
> A revoked page-cache read stays on ff->revoke_list until it completes.
> It's possible and legitimate that a second invalidation of the same
> inode is issued before a reply to the revoked read by userspace, so
> so drop the bogus WARN_ON_ONCE() and just skip it.
>
> https://virtuozzo.atlassian.net/browse/VSTOR-136315
>
> Signed-off-by: Liu Kui <kui.liu at virtuozzo.com>
> ---
>  fs/fuse/file.c | 12 ++++++++----
>  1 file changed, 8 insertions(+), 4 deletions(-)
>
> diff --git a/fs/fuse/file.c b/fs/fuse/file.c
> index e804e3c0d6bd..17f1a21b0445 100644
> --- a/fs/fuse/file.c
> +++ b/fs/fuse/file.c
> @@ -1225,11 +1225,15 @@ void fuse_revoke_readpages(struct fuse_file *ff)
>         spin_lock(&ff->lock);
>         /* revoke all pending read issued from page cache */
>         list_for_each_entry(ia, &ff->revoke_list, revoke_entry) {
> -               /* this should never happen unless userspace misbehaves */
> -               if (unlikely(ia->ap.args.killed)) {
> -                       WARN_ON_ONCE(1);
> +               /*
> +                * Already revoked by a previous invalidation and not yet completed,
> +                * its pages are already unlocked and its completion callback will
> +                * remove it from the list. This is a normal condition when the same
> +                * inode is invalidated more than once while a read is still outstanding,
> +                * so just skip it.
> +                */
> +               if (ia->ap.args.killed)
>                         continue;
> -               }
>                 ia->ap.args.killed = 1;
>                 for (i = 0; i < ia->ap.num_pages; i++)
>                         unlock_page(ia->ap.pages[i]);
> --
> 2.50.1 (Apple Git-155)