Patch "nfs: if we have no valid attrs, then don't declare the attribute cache valid" has been added to the 4.2-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    nfs: if we have no valid attrs, then don't declare the attribute cache valid

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nfs-if-we-have-no-valid-attrs-then-don-t-declare-the-attribute-cache-valid.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c812012f9ca7cf89c9e1a1cd512e6c3b5be04b85 Mon Sep 17 00:00:00 2001
From: Jeff Layton <jlayton@poochiereds.net>
Date: Wed, 25 Nov 2015 13:50:11 -0500
Subject: nfs: if we have no valid attrs, then don't declare the attribute cache valid

From: Jeff Layton <jlayton@poochiereds.net>

commit c812012f9ca7cf89c9e1a1cd512e6c3b5be04b85 upstream.

If we pass in an empty nfs_fattr struct to nfs_update_inode, it will
(correctly) not update any of the attributes, but it then clears the
NFS_INO_INVALID_ATTR flag, which indicates that the attributes are
up to date. Don't clear the flag if the fattr struct has no valid
attrs to apply.

Reviewed-by: Steve French <steve.french@primarydata.com>
Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 fs/nfs/inode.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -1816,7 +1816,11 @@ static int nfs_update_inode(struct inode
 		if ((long)fattr->gencount - (long)nfsi->attr_gencount > 0)
 			nfsi->attr_gencount = fattr->gencount;
 	}
-	invalid &= ~NFS_INO_INVALID_ATTR;
+
+	/* Don't declare attrcache up to date if there were no attrs! */
+	if (fattr->valid != 0)
+		invalid &= ~NFS_INO_INVALID_ATTR;
+
 	/* Don't invalidate the data if we were to blame */
 	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)
 				|| S_ISLNK(inode->i_mode)))


Patches currently in stable-queue which might be from jlayton@poochiereds.net are

queue-4.2/nfs-if-we-have-no-valid-attrs-then-don-t-declare-the-attribute-cache-valid.patch
queue-4.2/nfsd-serialize-state-seqid-morphing-operations.patch