Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Dai Ngo <dai.ngo@oracle.com>
To:     chuck.lever@oracle.com, jlayton@kernel.org
Cc:     linux-nfs@vger.kernel.org
Subject: [PATCH] NFSD: Fix problem of COMMIT and NFS4ERR_DELAY in infinite loop
Date:   Tue, 18 Apr 2023 13:31:31 -0700
Message-Id: <1681849891-29377-1-git-send-email-dai.ngo@oracle.com>
Precedence: bulk

The following request sequence to the same file causes the NFS client and
server to get into an infinite loop with COMMIT and NFS4ERR_DELAY:

OPEN
REMOVE
WRITE
COMMIT

Problem reported test recall11, recall12, recall14, recall20, recall22,
recall40, recall42, recall48, recall50 of nfstest suite.

This patch restores the handling of race condition in nfsd_file_do_acquire
with unlink to that prior of the regression.

Fixes: ac3a2585f018 ("nfsd: rework refcounting in filecache")
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
---
 fs/nfsd/filecache.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index 6e8712bd7c99..63f7d9f4ea99 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -1170,9 +1170,7 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	 * If construction failed, or we raced with a call to unlink()
 	 * then unhash.
 	 */
-	if (status == nfs_ok && key.inode->i_nlink == 0)
-		status = nfserr_jukebox;
-	if (status != nfs_ok)
+	if (status != nfs_ok || key.inode->i_nlink == 0)
 		nfsd_file_unhash(nf);
 	clear_bit_unlock(NFSD_FILE_PENDING, &nf->nf_flags);
 	smp_mb__after_atomic();
-- 
2.9.5