| Message ID | 20181220094921.3396-1-yuehaibing@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [net-next] svcrdma: Fix an uninitialized variable false warning | expand |
> On Dec 20, 2018, at 4:49 AM, YueHaibing <yuehaibing@huawei.com> wrote: > > smatch warning this: > net/sunrpc/xprtrdma/svc_rdma_rw.c:351 svc_rdma_post_chunk_ctxt() error: uninitialized symbol 'bad_wr' > net/sunrpc/xprtrdma/verbs.c:1569 rpcrdma_post_recvs() error: uninitialized symbol 'bad_wr' > > 'bad_wr' is initialized in ib_post_send. But smatch > doesn't know that and warns this. > > Signed-off-by: YueHaibing <yuehaibing@huawei.com> > --- > net/sunrpc/xprtrdma/svc_rdma_rw.c | 2 +- > net/sunrpc/xprtrdma/verbs.c | 2 +- > 2 files changed, 2 insertions(+), 2 deletions(-) > > diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c > index dc19517..0954b25 100644 > --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c > +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c > @@ -308,7 +308,7 @@ static int svc_rdma_post_chunk_ctxt(struct svc_rdma_chunk_ctxt *cc) > struct svcxprt_rdma *rdma = cc->cc_rdma; > struct svc_xprt *xprt = &rdma->sc_xprt; > struct ib_send_wr *first_wr; > - const struct ib_send_wr *bad_wr; > + const struct ib_send_wr *bad_wr = NULL; > struct list_head *tmp; > struct ib_cqe *cqe; > int ret; > diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c > index 3ddba94..37be70f 100644 > --- a/net/sunrpc/xprtrdma/verbs.c > +++ b/net/sunrpc/xprtrdma/verbs.c > @@ -1518,7 +1518,7 @@ void > rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp) > { > struct rpcrdma_buffer *buf = &r_xprt->rx_buf; > - struct ib_recv_wr *wr, *bad_wr; > + struct ib_recv_wr *wr, *bad_wr = NULL; > int needed, count, rc; > > rc = 0; > -- > 2.7.0 Does this need Fixes: d34ac5cd3a73 ("RDMA, core and ULPs: Declare ib_post_send() and ib_post_recv() arguments const") ??? Bart, any comments? -- Chuck Lever
On Fri, 2018-12-28 at 10:36 -0500, Chuck Lever wrote: > > On Dec 20, 2018, at 4:49 AM, YueHaibing <yuehaibing@huawei.com> wrote: > > > > smatch warning this: > > net/sunrpc/xprtrdma/svc_rdma_rw.c:351 svc_rdma_post_chunk_ctxt() error: uninitialized symbol 'bad_wr' > > net/sunrpc/xprtrdma/verbs.c:1569 rpcrdma_post_recvs() error: uninitialized symbol 'bad_wr' > > > > 'bad_wr' is initialized in ib_post_send. But smatch > > doesn't know that and warns this. > > > > Signed-off-by: YueHaibing <yuehaibing@huawei.com> > > --- > > net/sunrpc/xprtrdma/svc_rdma_rw.c | 2 +- > > net/sunrpc/xprtrdma/verbs.c | 2 +- > > 2 files changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c > > index dc19517..0954b25 100644 > > --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c > > +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c > > @@ -308,7 +308,7 @@ static int svc_rdma_post_chunk_ctxt(struct svc_rdma_chunk_ctxt *cc) > > struct svcxprt_rdma *rdma = cc->cc_rdma; > > struct svc_xprt *xprt = &rdma->sc_xprt; > > struct ib_send_wr *first_wr; > > - const struct ib_send_wr *bad_wr; > > + const struct ib_send_wr *bad_wr = NULL; > > struct list_head *tmp; > > struct ib_cqe *cqe; > > int ret; > > diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c > > index 3ddba94..37be70f 100644 > > --- a/net/sunrpc/xprtrdma/verbs.c > > +++ b/net/sunrpc/xprtrdma/verbs.c > > @@ -1518,7 +1518,7 @@ void > > rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp) > > { > > struct rpcrdma_buffer *buf = &r_xprt->rx_buf; > > - struct ib_recv_wr *wr, *bad_wr; > > + struct ib_recv_wr *wr, *bad_wr = NULL; > > int needed, count, rc; > > > > rc = 0; > > -- > > 2.7.0 > > Does this need > > Fixes: d34ac5cd3a73 ("RDMA, core and ULPs: Declare ib_post_send() and ib_post_recv() arguments const") ??? > > Bart, any comments? Hi Chuck, My understanding is that the "Fixes:" tag should only be used for patches that fix bugs. Since this patch addresses a false positive warning reported by smatch I think that it would be misleading to use the "Fixes:" tag. Before proceeding with this patch, I think that smatch should be improved. The following patch namely was not sufficient to suppress the xprtrdma warning reported by smatch: diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h index a3ceed3a040a..498eaa245d1a 100644 --- a/include/rdma/ib_verbs.h +++ b/include/rdma/ib_verbs.h @@ -3327,9 +3327,16 @@ static inline int ib_post_srq_recv(struct ib_srq *srq, const struct ib_recv_wr **bad_recv_wr) { const struct ib_recv_wr *dummy; - - return srq->device->ops.post_srq_recv(srq, recv_wr, - bad_recv_wr ? : &dummy); + int ret; + + ret = srq->device->ops.post_srq_recv(srq, recv_wr, + bad_recv_wr ? : &dummy); +#ifdef __CHECKER__ + /* Tell static analyzers that *bad_send_wr is initialized if ret != 0 */ + if (ret && bad_send_wr) + *bad_send_wr = *bad_send_wr; +#endif + return ret; } /** @@ -3431,8 +3438,15 @@ static inline int ib_post_send(struct ib_qp *qp, const struct ib_send_wr **bad_send_wr) { const struct ib_send_wr *dummy; + int ret; - return qp->device->ops.post_send(qp, send_wr, bad_send_wr ? : &dummy); + ret = qp->device->ops.post_send(qp, send_wr, bad_send_wr ? : &dummy); +#ifdef __CHECKER__ + /* Tell static analyzers that *bad_send_wr is initialized if ret != 0 */ + if (ret && bad_send_wr) + *bad_send_wr = *bad_send_wr; +#endif + return ret; } /** @@ -3448,8 +3462,15 @@ static inline int ib_post_recv(struct ib_qp *qp, const struct ib_recv_wr **bad_recv_wr) { const struct ib_recv_wr *dummy; + int ret; - return qp->device->ops.post_recv(qp, recv_wr, bad_recv_wr ? : &dummy); + ret = qp->device->ops.post_recv(qp, recv_wr, bad_recv_wr ? : &dummy); +#ifdef __CHECKER__ + /* Tell static analyzers that *bad_send_wr is initialized if ret != 0 */ + if (ret && bad_send_wr) + *bad_send_wr = *bad_send_wr; +#endif + return ret; } struct ib_cq *__ib_alloc_cq(struct ib_device *dev, void *private, Bart.
diff --git a/net/sunrpc/xprtrdma/svc_rdma_rw.c b/net/sunrpc/xprtrdma/svc_rdma_rw.c index dc19517..0954b25 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_rw.c +++ b/net/sunrpc/xprtrdma/svc_rdma_rw.c @@ -308,7 +308,7 @@ static int svc_rdma_post_chunk_ctxt(struct svc_rdma_chunk_ctxt *cc) struct svcxprt_rdma *rdma = cc->cc_rdma; struct svc_xprt *xprt = &rdma->sc_xprt; struct ib_send_wr *first_wr; - const struct ib_send_wr *bad_wr; + const struct ib_send_wr *bad_wr = NULL; struct list_head *tmp; struct ib_cqe *cqe; int ret; diff --git a/net/sunrpc/xprtrdma/verbs.c b/net/sunrpc/xprtrdma/verbs.c index 3ddba94..37be70f 100644 --- a/net/sunrpc/xprtrdma/verbs.c +++ b/net/sunrpc/xprtrdma/verbs.c @@ -1518,7 +1518,7 @@ void rpcrdma_post_recvs(struct rpcrdma_xprt *r_xprt, bool temp) { struct rpcrdma_buffer *buf = &r_xprt->rx_buf; - struct ib_recv_wr *wr, *bad_wr; + struct ib_recv_wr *wr, *bad_wr = NULL; int needed, count, rc; rc = 0;
smatch warning this: net/sunrpc/xprtrdma/svc_rdma_rw.c:351 svc_rdma_post_chunk_ctxt() error: uninitialized symbol 'bad_wr' net/sunrpc/xprtrdma/verbs.c:1569 rpcrdma_post_recvs() error: uninitialized symbol 'bad_wr' 'bad_wr' is initialized in ib_post_send. But smatch doesn't know that and warns this. Signed-off-by: YueHaibing <yuehaibing@huawei.com> --- net/sunrpc/xprtrdma/svc_rdma_rw.c | 2 +- net/sunrpc/xprtrdma/verbs.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)