FAILED: patch "[PATCH] xprtrdma: Return -ENOBUFS when no pages are available" failed to apply to 4.9-stable tree

FAILED: patch "[PATCH] xprtrdma: Return -ENOBUFS when no pages are available" failed to apply to 4.9-stable tree

[gregkh]

The patch below does not apply to the 4.9-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 a8f688ec437dc2045cc8f0c89fe877d5803850da Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Fri, 4 May 2018 15:35:46 -0400
Subject: [PATCH] xprtrdma: Return -ENOBUFS when no pages are available

The use of -EAGAIN in rpcrdma_convert_iovs() is a latent bug: the
transport never calls xprt_write_space() when more pages become
available. -ENOBUFS will trigger the correct "delay briefly and call
again" logic.

Fixes: 7a89f9c626e3 ("xprtrdma: Honor ->send_request API contract")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # 4.8+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index d676106295ff..1d7857919d3d 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -231,7 +231,7 @@ rpcrdma_convert_iovs(struct rpcrdma_xprt *r_xprt, struct xdr_buf *xdrbuf,
 			 */
 			*ppages = alloc_page(GFP_ATOMIC);
 			if (!*ppages)
-				return -EAGAIN;
+				return -ENOBUFS;
 		}
 		seg->mr_page = *ppages;
 		seg->mr_offset = (char *)page_base;

Re: FAILED: patch "[PATCH] xprtrdma: Return -ENOBUFS when no pages are available" failed to apply to 4.9-stable tree

[Sudip Mukherjee]

[-- Attachment #1: Type: text/plain, Size: 403 bytes --]

Hi Greg,

On Sun, Jul 01, 2018 at 11:52:35AM +0200, gregkh@linuxfoundation.org wrote:
> 
> The patch below does not apply to the 4.9-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>.

The attached backported patch should apply to 4.9-stable.

--
Regards
Sudip

[-- Attachment #2: 0001-xprtrdma-Return-ENOBUFS-when-no-pages-are-available.patch --]
[-- Type: text/x-diff, Size: 1402 bytes --]

>From 9562dcbaa81ad0853f0971e050cc9972c7af3d40 Mon Sep 17 00:00:00 2001
From: Chuck Lever <chuck.lever@oracle.com>
Date: Fri, 4 May 2018 15:35:46 -0400
Subject: [PATCH] xprtrdma: Return -ENOBUFS when no pages are available

commit a8f688ec437dc2045cc8f0c89fe877d5803850da upstream

The use of -EAGAIN in rpcrdma_convert_iovs() is a latent bug: the
transport never calls xprt_write_space() when more pages become
available. -ENOBUFS will trigger the correct "delay briefly and call
again" logic.

Fixes: 7a89f9c626e3 ("xprtrdma: Honor ->send_request API contract")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org # 4.8+
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
---
 net/sunrpc/xprtrdma/rpc_rdma.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/sunrpc/xprtrdma/rpc_rdma.c b/net/sunrpc/xprtrdma/rpc_rdma.c
index f57c9f0ab8f9..0287734f126f 100644
--- a/net/sunrpc/xprtrdma/rpc_rdma.c
+++ b/net/sunrpc/xprtrdma/rpc_rdma.c
@@ -229,7 +229,7 @@ rpcrdma_convert_iovs(struct rpcrdma_xprt *r_xprt, struct xdr_buf *xdrbuf,
 			/* alloc the pagelist for receiving buffer */
 			ppages[p] = alloc_page(GFP_ATOMIC);
 			if (!ppages[p])
-				return -EAGAIN;
+				return -ENOBUFS;
 		}
 		seg[n].mr_page = ppages[p];
 		seg[n].mr_offset = (void *)(unsigned long) page_base;
-- 
2.11.0

Re: FAILED: patch "[PATCH] xprtrdma: Return -ENOBUFS when no pages are available" failed to apply to 4.9-stable tree

[Greg KH]

On Sun, Jul 22, 2018 at 12:09:01AM +0100, Sudip Mukherjee wrote:
> Hi Greg,
> 
> On Sun, Jul 01, 2018 at 11:52:35AM +0200, gregkh@linuxfoundation.org wrote:
> > 
> > The patch below does not apply to the 4.9-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>.
> 
> The attached backported patch should apply to 4.9-stable.

Now applied, thanks.

greg k-h