NFSv4: Clear the NFS_CAP_XATTR flag if not supported by the server

JIRA: https://issues.redhat.com/browse/RHEL-108616

commit 4fb2b67
Author: Trond Myklebust <trond.myklebust@hammerspace.com>
Date:   Fri Aug 29 09:15:12 2025 -0700

    NFSv4: Clear the NFS_CAP_XATTR flag if not supported by the server

    nfs_server_set_fsinfo() shouldn't assume that NFS_CAP_XATTR is unset
    on entry to the function.

    Fixes: b78ef84 ("NFSv4.2: query the server for extended attribute support")
    Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>

Author: bcodding-rh

fs/nfs/client.c

@@ -869,6 +869,8 @@ static void nfs_server_set_fsinfo(struct nfs_server *server,
 
 	if (fsinfo->xattr_support)
 		server->caps |= NFS_CAP_XATTR;
+	else
+		server->caps &= ~NFS_CAP_XATTR;
 #endif
 }