From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:37870) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dXXn5-0003eo-1E for qemu-devel@nongnu.org; Tue, 18 Jul 2017 15:04:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dXXn0-0002TX-5J for qemu-devel@nongnu.org; Tue, 18 Jul 2017 15:04:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48062) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dXXmz-0002SZ-WA for qemu-devel@nongnu.org; Tue, 18 Jul 2017 15:04:10 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id AAEEFC04B939 for ; Tue, 18 Jul 2017 19:04:08 +0000 (UTC) Date: Tue, 18 Jul 2017 20:04:02 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20170718190402.GG2106@work-vm> References: <20170717110936.23314-1-dgilbert@redhat.com> <20170717110936.23314-4-dgilbert@redhat.com> <20170718012042.GW27284@pxdev.xzpeter.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20170718012042.GW27284@pxdev.xzpeter.org> Subject: Re: [Qemu-devel] [PATCH v4 3/6] migration/rdma: fix qemu_rdma_block_for_wrid error paths List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Xu Cc: qemu-devel@nongnu.org, quintela@redhat.com, lvivier@redhat.com * Peter Xu (peterx@redhat.com) wrote: > On Mon, Jul 17, 2017 at 12:09:33PM +0100, Dr. David Alan Gilbert (git) wr= ote: > > From: "Dr. David Alan Gilbert" > >=20 > > The two places that 'goto err_block_for_wrid' weren't setting ret > > and so would end up returning 0 even though we've failed. > >=20 > > Signed-off-by: Dr. David Alan Gilbert > > --- > > migration/rdma.c | 8 ++++++-- > > 1 file changed, 6 insertions(+), 2 deletions(-) > >=20 > > diff --git a/migration/rdma.c b/migration/rdma.c > > index 6111e10c70..59810aec2e 100644 > > --- a/migration/rdma.c > > +++ b/migration/rdma.c > > @@ -1521,14 +1521,16 @@ static int qemu_rdma_block_for_wrid(RDMAContext= *rdma, int wrid_requested, > > yield_until_fd_readable(rdma->comp_channel->fd); > > } > > =20 > > - if (ibv_get_cq_event(rdma->comp_channel, &cq, &cq_ctx)) { > > + ret =3D ibv_get_cq_event(rdma->comp_channel, &cq, &cq_ctx); > > + if (ret) { > > perror("ibv_get_cq_event"); > > goto err_block_for_wrid; > > } > > =20 > > num_cq_events++; > > =20 > > - if (ibv_req_notify_cq(cq, 0)) { > > + ret =3D -ibv_req_notify_cq(cq, 0); >=20 > (I didn't really notice that it is returning a positive value for > error...) Yes, the manpage said that and I followed it into the source to check; none of the ibv interfaces are in any way consistent. =46rom the manpage: ibv_get_cq_event() returns 0 on success, and -1 on error. ibv_ack_cq_events() returns no value. ibv_req_notify_cq() returns 0 on success, or the value of errno on failu= re etc (and -1 will do as a ret value if we havent got a real errno) Dave > Reviewed-by: Peter Xu >=20 > > + if (ret) { > > goto err_block_for_wrid; > > } > > =20 > > @@ -1564,6 +1566,8 @@ err_block_for_wrid: > > if (num_cq_events) { > > ibv_ack_cq_events(cq, num_cq_events); > > } > > + > > + rdma->error_state =3D ret; > > return ret; > > } > > =20 > > --=20 > > 2.13.0 > >=20 >=20 > --=20 > Peter Xu -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK