Return-Path: Received: from fieldses.org ([173.255.197.46]:60072 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730AbdALVPg (ORCPT ); Thu, 12 Jan 2017 16:15:36 -0500 Date: Thu, 12 Jan 2017 16:15:35 -0500 From: "J. Bruce Fields" To: Chuck Lever Cc: Sriharsha Basavapatna , Yuval Shaia , Linux NFS Mailing List , List Linux RDMA Mailing Subject: Re: [PATCH] svcrdma: avoid duplicate dma unmapping during error recovery Message-ID: <20170112211535.GE10501@fieldses.org> References: <20170109103044.5590-1-sriharsha.basavapatna@broadcom.com> <20170109064224.GA3820@yuval-lap> <5761AF19-DF8B-44CE-B744-C21464958041@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <5761AF19-DF8B-44CE-B744-C21464958041@oracle.com> Sender: linux-nfs-owner@vger.kernel.org List-ID: On Mon, Jan 09, 2017 at 10:05:48AM -0500, Chuck Lever wrote: > > > On Jan 9, 2017, at 1:42 AM, Yuval Shaia wrote: > > > > On Mon, Jan 09, 2017 at 04:00:44PM +0530, Sriharsha Basavapatna wrote: > >> In rdma_read_chunk_frmr() when ib_post_send() fails, the error code path > >> invokes ib_dma_unmap_sg() to unmap the sg list. It then invokes > >> svc_rdma_put_frmr() which in turn tries to unmap the same sg list through > >> ib_dma_unmap_sg() again. This second unmap is invalid and could lead to > >> problems when the iova being unmapped is subsequently reused. Remove > >> the call to unmap in rdma_read_chunk_frmr() and let svc_rdma_put_frmr() > >> handle it. > >> > >> Fixes: 412a15c0fe53 ("svcrdma: Port to new memory registration API") > >> Cc: stable@vger.kernel.org > >> Signed-off-by: Sriharsha Basavapatna > >> Reviewed-by: Chuck Lever > >> --- > >> net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 2 -- > >> 1 file changed, 2 deletions(-) > >> > >> diff --git a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > >> index 57d35fbb1c28..172b537f8cfc 100644 > >> --- a/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > >> +++ b/net/sunrpc/xprtrdma/svc_rdma_recvfrom.c > >> @@ -347,8 +347,6 @@ int rdma_read_chunk_frmr(struct svcxprt_rdma *xprt, > >> atomic_inc(&rdma_stat_read); > >> return ret; > >> err: > >> - ib_dma_unmap_sg(xprt->sc_cm_id->device, > >> - frmr->sg, frmr->sg_nents, frmr->direction); > >> svc_rdma_put_context(ctxt, 0); > >> svc_rdma_put_frmr(xprt, frmr); > >> return ret; > > > > Reviewed-by: Yuval Shaia > > Hi Bruce- > > Is it possible to take this in v4.10-rc ? Yep, thanks to all of you.--b.