Re: [PATCH] nfsd: fix net-namespace logic in __nfsd_file_cache_purge
From: Chuck Lever III <chuck.lever@oracle.com>
Date: 2022-10-31 15:41:44
On Oct 31, 2022, at 11:35 AM, Jeff Layton [off-list ref] 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@suse.cz>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
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?
quoted hunk ↗ jump to hunk
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