> On Oct 31, 2022, at 11:35 AM, Jeff Layton <jlayton@xxxxxxxxxx> wrote:
>
> If the namespace doesn't match the one in "net", then we'll continue,
> but that doesn't cause another rhashtable_walk_next call, so it will
> loop infinitely.
>
> Fixes: ce502f81ba88 ("NFSD: Convert the filecache to use rhashtable")
> Reported-by: Petr Vorel <pvorel@xxxxxxx>
> Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> ---
> fs/nfsd/filecache.c | 20 +++++++++-----------
> 1 file changed, 9 insertions(+), 11 deletions(-)
>
> This should probably go to stable too.
I tried to apply this to for-rc, but the WARN_ON_ONCE logic
has already been removed there. Can you rebase and resend?
> diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
> index eeed4ae5b4ad..f9ea89057ae8 100644
> --- a/fs/nfsd/filecache.c
> +++ b/fs/nfsd/filecache.c
> @@ -908,19 +908,17 @@ __nfsd_file_cache_purge(struct net *net)
>
> nf = rhashtable_walk_next(&iter);
> while (!IS_ERR_OR_NULL(nf)) {
> - if (net && nf->nf_net != net)
> - continue;
> - del = nfsd_file_unhash_and_dispose(nf, &dispose);
> -
> - /*
> - * Deadlock detected! Something marked this entry as
> - * unhased, but hasn't removed it from the hash list.
> - */
> - WARN_ON_ONCE(!del);
> -
> + if (!net || nf->nf_net == net) {
> + del = nfsd_file_unhash_and_dispose(nf, &dispose);
> +
> + /*
> + * Deadlock detected! Something marked this entry as
> + * unhased, but hasn't removed it from the hash list.
> + */
> + WARN_ON_ONCE(!del);
> + }
> nf = rhashtable_walk_next(&iter);
> }
> -
> rhashtable_walk_stop(&iter);
> } while (nf == ERR_PTR(-EAGAIN));
> rhashtable_walk_exit(&iter);
> --
> 2.38.1
>
--
Chuck Lever
