From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: linux-next: build warning after merge of the rdma tree Date: Thu, 26 Jul 2018 11:38:06 -0600 Message-ID: <20180726173806.GG10178@mellanox.com> References: <20180726105553.00a36e3c@canb.auug.org.au> <20180726030503.GA18170@mellanox.com> <36211fbe8a548742cf8e41a57f02f81e55c86794.camel@wdc.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <36211fbe8a548742cf8e41a57f02f81e55c86794.camel@wdc.com> Sender: linux-kernel-owner@vger.kernel.org To: Bart Van Assche Cc: "sfr@canb.auug.org.au" , "linux-kernel@vger.kernel.org" , "linux-next@vger.kernel.org" , "dledford@redhat.com" , "chuck.lever@oracle.com" List-Id: linux-next.vger.kernel.org On Thu, Jul 26, 2018 at 05:10:13AM +0000, Bart Van Assche wrote: > On Wed, 2018-07-25 at 21:05 -0600, Jason Gunthorpe wrote: > > On Thu, Jul 26, 2018 at 10:55:53AM +1000, Stephen Rothwell wrote: > > > Hi all, > > > > > > After merging the rdma tree, today's linux-next build (powerpc > > > ppc64_defconfig) produced this warning: > > > > > > net/sunrpc/xprtrdma/svc_rdma_rw.c: In function 'svc_rdma_post_chunk_ctxt': > > > net/sunrpc/xprtrdma/svc_rdma_rw.c:350:5: warning: 'bad_wr' may be used uninitialized in this function [-Wmaybe-uninitialized] > > > if (bad_wr != first_wr) > > > ^ > > > > Huh. I'm quite surprised 0-day build service didn't warn on this. > > > > > Introduced by commit > > > > > > ed288d74a9e5 ("net/xprtrdma: Simplify ib_post_(send|recv|srq_recv)() calls") > > > > > > This is an actual problem. > > > > Yes, for sure. Bart? > > Thanks Stephen for having reported this. I propose to revert the changes in > net/sunrpc/xprtrdma/svc_rdma_rw.c. Jason, do you want me to submit the below > as a formal patch? I applied the below.. Please let me know if there is an error. Thanks, Jason commit 5d85a822fae2b484f26ddb09815063a88962a0cb Author: Jason Gunthorpe Date: Thu Jul 26 11:36:50 2018 -0600 net/xprtrdma: Restore needed argument to ib_post_send The call in svc_rdma_post_chunk_ctxt() does actually use bad_wr. Fixes: ed288d74a9e5 ("net/xprtrdma: Simplify ib_post_(send|recv|srq_recv)() calls") Reported-by: Stephen Rothwell Signed-off-by: Bart Van Assche Signed-off-by: Jason Gunthorpe diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c index 80975427f5235f..ce3ea841970483 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -329,7 +329,7 @@ static int svc_rdma_post_chunk_ctxt(struct svc_rdma_chunk_ctxt *cc) do { if (atomic_sub_return(cc->cc_sqecount, &rdma->sc_sq_avail) > 0) { - ret = ib_post_send(rdma->sc_qp, first_wr, NULL); + ret = ib_post_send(rdma->sc_qp, first_wr, &bad_wr); trace_svcrdma_post_rw(&cc->cc_cqe, cc->cc_sqecount, ret); if (ret)