From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:55824 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751154AbcJENXj (ORCPT ); Wed, 5 Oct 2016 09:23:39 -0400 Subject: Patch "xprtrdma: Remove FMRs from the unmap list after unmapping" has been added to the 4.7-stable tree To: chuck.lever@oracle.com, Anna.Schumaker@Netapp.com, gregkh@linuxfoundation.org, swise@opengridcomputing.com Cc: , From: Date: Wed, 05 Oct 2016 15:20:53 +0200 Message-ID: <1475673653219210@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: This is a note to let you know that I've just added the patch titled xprtrdma: Remove FMRs from the unmap list after unmapping to the 4.7-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: xprtrdma-remove-fmrs-from-the-unmap-list-after-unmapping.patch and it can be found in the queue-4.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let know about it. >>From 38f1932e60ba249660bbae585f61ef2dee3313a4 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Wed, 29 Jun 2016 13:52:12 -0400 Subject: xprtrdma: Remove FMRs from the unmap list after unmapping From: Chuck Lever commit 38f1932e60ba249660bbae585f61ef2dee3313a4 upstream. ib_unmap_fmr() takes a list of FMRs to unmap. However, it does not remove the FMRs from this list as it processes them. Other ib_unmap_fmr() call sites are careful to remove FMRs from the list after ib_unmap_fmr() returns. Since commit 7c7a5390dc6c8 ("xprtrdma: Add ro_unmap_sync method for FMR") fmr_op_unmap_sync passes more than one FMR to ib_unmap_fmr(), but it didn't bother to remove the FMRs from that list once the call was complete. I've noticed some instability that could be related to list tangling by the new fmr_op_unmap_sync() logic. In an abundance of caution, add some defensive logic to clean up properly after ib_unmap_fmr(). Fixes: 7c7a5390dc6c8 ("xprtrdma: Add ro_unmap_sync method for FMR") Signed-off-by: Chuck Lever Tested-by: Steve Wise Signed-off-by: Anna Schumaker Signed-off-by: Greg Kroah-Hartman --- net/sunrpc/xprtrdma/fmr_ops.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) --- a/net/sunrpc/xprtrdma/fmr_ops.c +++ b/net/sunrpc/xprtrdma/fmr_ops.c @@ -63,9 +63,12 @@ static int __fmr_unmap(struct rpcrdma_mw *mw) { LIST_HEAD(l); + int rc; list_add(&mw->fmr.fmr->list, &l); - return ib_unmap_fmr(&l); + rc = ib_unmap_fmr(&l); + list_del_init(&mw->fmr.fmr->list); + return rc; } /* Deferred reset of a single FMR. Generate a fresh rkey by @@ -267,7 +270,7 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r seg = &req->rl_segments[i]; mw = seg->rl_mw; - list_add(&mw->fmr.fmr->list, &unmap_list); + list_add_tail(&mw->fmr.fmr->list, &unmap_list); i += seg->mr_nsegs; } @@ -280,7 +283,9 @@ fmr_op_unmap_sync(struct rpcrdma_xprt *r */ for (i = 0, nchunks = req->rl_nchunks; nchunks; nchunks--) { seg = &req->rl_segments[i]; + mw = seg->rl_mw; + list_del_init(&mw->fmr.fmr->list); __fmr_dma_unmap(r_xprt, seg); rpcrdma_put_mw(r_xprt, seg->rl_mw); Patches currently in stable-queue which might be from chuck.lever@oracle.com are queue-4.7/xprtrdma-remove-fmrs-from-the-unmap-list-after-unmapping.patch queue-4.7/svc-avoid-garbage-replies-when-pc_func-returns-rpc_drop_reply.patch queue-4.7/nfs-don-t-drop-cb-requests-with-invalid-principals.patch