svcrdma: avoid duplicate dma unmapping during error recovery
diff mbox

Message ID 20170104160329.24436-1-sriharsha.basavapatna@broadcom.com
State New
Headers show

Commit Message

Sriharsha Basavapatna Jan. 4, 2017, 4:03 p.m. UTC
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 <sriharsha.basavapatna@broadcom.com>
---
 net/sunrpc/xprtrdma/svc_rdma_recvfrom.c | 2 --
 1 file changed, 2 deletions(-)

Comments

Chuck Lever Jan. 4, 2017, 6:20 p.m. UTC | #1
> On Jan 4, 2017, at 11:03 AM, Sriharsha Basavapatna <sriharsha.basavapatna@broadcom.com> 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 <sriharsha.basavapatna@broadcom.com>

Reviewed-by: Chuck Lever <chuck.lever@oracle.com>


> ---
> 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;
> -- 
> 2.11.0.258.ge05806da9
> 
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--
Chuck Lever



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Patch
diff mbox

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;