diff mbox series

NFS/pnfs: Fix a live lock between recalled layouts and layoutget

Message ID 0688a7b30bfe847ccab1feca8dde7617036e7ca8.1734439172.git.trond.myklebust@hammerspace.com (mailing list archive)
State New
Headers show
Series NFS/pnfs: Fix a live lock between recalled layouts and layoutget | expand

Commit Message

Trond Myklebust Dec. 17, 2024, 3:40 p.m. UTC
From: Trond Myklebust <trond.myklebust@hammerspace.com>

When the server is recalling a layout, we should ignore the count of
outstanding layoutget calls, since the server is expected to return
either NFS4ERR_RECALLCONFLICT or NFS4ERR_RETURNCONFLICT for as long as
the recall is outstanding.
Currently, we may end up livelocking, causing the layout to eventually
be forcibly revoked.

Fixes: bf0291dd2267 ("pNFS: Ensure LAYOUTGET and LAYOUTRETURN are properly serialised")
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
 fs/nfs/pnfs.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 0d16b383a452..5f582713bf05 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1308,7 +1308,7 @@  pnfs_prepare_layoutreturn(struct pnfs_layout_hdr *lo,
 		enum pnfs_iomode *iomode)
 {
 	/* Serialise LAYOUTGET/LAYOUTRETURN */
-	if (atomic_read(&lo->plh_outstanding) != 0)
+	if (atomic_read(&lo->plh_outstanding) != 0 && lo->plh_return_seq == 0)
 		return false;
 	if (test_and_set_bit(NFS_LAYOUT_RETURN_LOCK, &lo->plh_flags))
 		return false;