From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40276) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YzlyF-00064B-77 for qemu-devel@nongnu.org; Tue, 02 Jun 2015 09:11:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YzlyA-0004yl-IS for qemu-devel@nongnu.org; Tue, 02 Jun 2015 09:11:07 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42286) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YzlyA-0004yV-4U for qemu-devel@nongnu.org; Tue, 02 Jun 2015 09:11:02 -0400 Date: Tue, 2 Jun 2015 14:10:57 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20150602131054.GB2139@work-vm> References: <1433286850-12753-1-git-send-email-padmanabh.ratnakar@avagotech.com> <87pp5e9sji.fsf@neno.neno> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87pp5e9sji.fsf@neno.neno> Subject: Re: [Qemu-devel] [PATCH] rdma: Fix qemu crash when IPv6 address is used for migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Juan Quintela Cc: amit.shah@redhat.com, Meghana Cheripady , mrhines@us.ibm.com, qemu-devel@nongnu.org, Padmanabh Ratnakar * Juan Quintela (quintela@redhat.com) wrote: > Padmanabh Ratnakar wrote: > > Qemu crashes when IPv6 address is specified for migration and access > > to any RDMA uverbs device available on the system is blocked using cgroups. > > Fix the crash by checking the return value of ibv_open_device routine. > > > > Signed-off-by: Meghana Cheripady > > Signed-off-by: Padmanabh Ratnakar > > --- > > migration/rdma.c | 7 +++++++ > > 1 files changed, 7 insertions(+), 0 deletions(-) > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > index 77e3444..3671903 100644 > > --- a/migration/rdma.c > > +++ b/migration/rdma.c > > @@ -790,6 +790,13 @@ static int qemu_rdma_broken_ipv6_kernel(Error **errp, struct ibv_context *verbs) > > > > for (x = 0; x < num_devices; x++) { > > verbs = ibv_open_device(dev_list[x]); > > + if (!verbs) { > > + if (errno == EPERM) { > > + continue; > > Why do we want to continue here? I think the idea is to loop through the set of devices and find if any of them are 'roce'; if one of the devices iwe don't have permission to use then it's probably ok to skip and move onto the next one? > > + } else { > > + return -EINVAL; > > + } > > + } > > > > if (ibv_query_port(verbs, 1, &port_attr)) { > > > Reading the documentation, my understandig is that if verbs is NULL, we > don't have a context to do anything useful here, no? But that's OK because of the if (!verbs) above? > > ibv_close_device(verbs); > > > Thanks, Juan. Dave > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK