[PATCH 6.1 016/451] NFSD: Fix problem of COMMIT and NFS4ERR_DELAY in infinite loop

From: Sasha Levin
Date: Sun Mar 24 2024 - 23:27:21 EST


From: Dai Ngo <dai.ngo@xxxxxxxxxx>

[ Upstream commit 147abcacee33781e75588869e944ddb07528a897 ]

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

OPEN
REMOVE
WRITE
COMMIT

Problem reported by 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@xxxxxxxxxx>
Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/nfsd/filecache.c | 2 --
1 file changed, 2 deletions(-)

diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c
index f40d8f3b35a4c..ee9c923192e08 100644
--- a/fs/nfsd/filecache.c
+++ b/fs/nfsd/filecache.c
@@ -1099,8 +1099,6 @@ nfsd_file_do_acquire(struct svc_rqst *rqstp, struct svc_fh *fhp,
* then unhash.
*/
if (status != nfs_ok || inode->i_nlink == 0)
- status = nfserr_jukebox;
- if (status != nfs_ok)
nfsd_file_unhash(nf);
clear_and_wake_up_bit(NFSD_FILE_PENDING, &nf->nf_flags);
if (status == nfs_ok)
--
2.43.0