5.4-stable review patch. If anyone has any objections, please let me know.
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From: Benjamin Coddington bcodding@redhat.com
commit 3b816601e279756e781e6c4d9b3f3bd21a72ac67 upstream.
We have some reports of linux NFS clients that cannot satisfy a linux knfsd server that always sets SEQ4_STATUS_RECALLABLE_STATE_REVOKED even though those clients repeatedly walk all their known state using TEST_STATEID and receive NFS4_OK for all.
Its possible for revoke_delegation() to set NFS4_REVOKED_DELEG_STID, then nfsd4_free_stateid() finds the delegation and returns NFS4_OK to FREE_STATEID. Afterward, revoke_delegation() moves the same delegation to cl_revoked. This would produce the observed client/server effect.
Fix this by ensuring that the setting of sc_type to NFS4_REVOKED_DELEG_STID and move to cl_revoked happens within the same cl_lock. This will allow nfsd4_free_stateid() to properly remove the delegation from cl_revoked.
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2217103 Link: https://bugzilla.redhat.com/show_bug.cgi?id=2176575 Signed-off-by: Benjamin Coddington bcodding@redhat.com Cc: stable@vger.kernel.org # v4.17+ Reviewed-by: Jeff Layton jlayton@kernel.org Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfsd/nfs4state.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -1096,9 +1096,9 @@ static void revoke_delegation(struct nfs WARN_ON(!list_empty(&dp->dl_recall_lru));
if (clp->cl_minorversion) { + spin_lock(&clp->cl_lock); dp->dl_stid.sc_type = NFS4_REVOKED_DELEG_STID; refcount_inc(&dp->dl_stid.sc_count); - spin_lock(&clp->cl_lock); list_add(&dp->dl_recall_lru, &clp->cl_revoked); spin_unlock(&clp->cl_lock); }