FAILED: patch "[PATCH] nfs: remove WARN_ON_ONCE from nfs_direct_good_bytes" failed to apply to 3.19-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 3.19-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From 05f54903d9d370a4cd302a85681304d3ec59e5c1 Mon Sep 17 00:00:00 2001
From: Peng Tao <tao.peng@primarydata.com>
Date: Thu, 9 Apr 2015 23:02:17 +0800
Subject: [PATCH] nfs: remove WARN_ON_ONCE from nfs_direct_good_bytes

For flexfiles driver, we might choose to read from mirror index other
than 0 while mirror_count is always 1 for read.

Reported-by: Jean Spector <jean@primarydata.com>
Cc: <stable@vger.kernel.org> # v3.19+
Cc: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index e97a67e40b48..eeb52b434e6f 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -129,8 +129,6 @@ nfs_direct_good_bytes(struct nfs_direct_req *dreq, struct nfs_pgio_header *hdr)
 	int i;
 	ssize_t count;
 
-	WARN_ON_ONCE(hdr->pgio_mirror_idx >= dreq->mirror_count);
-
 	if (dreq->mirror_count == 1) {
 		dreq->mirrors[hdr->pgio_mirror_idx].count += hdr->good_bytes;
 		dreq->count += hdr->good_bytes;