Re: Missing infiniband network interfaces after update to 5.14/5.15

[Jason Gunthorpe <jgg@ziepe.ca>]

On Fri, Nov 12, 2021 at 09:23:04AM +0100, Jinpu Wang wrote:
> On Thu, Nov 11, 2021 at 12:29 PM Leon Romanovsky <leon@kernel.org> wrote:
> >
> > On Thu, Nov 11, 2021 at 08:48:08AM +0100, Jinpu Wang wrote:
> > > Hi Jason, hi Leon,
> > >
> > > We are seeing exactly the same error reported here:
> > > https://bugzilla.redhat.com/show_bug.cgi?id=2014094
> > >
> > > I suspect it's related to
> > > https://lore.kernel.org/all/cover.1623427137.git.leonro@nvidia.com/
> > >
> > > Do you have any idea, what goes wrong?
> >
> > I can't reproduce it with latest Fedora 34 RPM, which I downloaded from here
> > https://koji.fedoraproject.org/koji/buildinfo?buildID=1851842
> >
> > and also with kernel-5.14.7-200.fc34.x86_64 version mentioned in the bug
> > report.
> >
> > [leonro@c-235-8-1-005 ~]$ uname -a
> > Linux c-235-8-1-005 5.14.7-200.fc34.x86_64 #1 SMP Wed Sep 22 14:54:28 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
> > [leonro@c-235-8-1-005 ~]$ rdma dev
> > 0: ibp8s0f0: node_type ca fw 2.42.5000 node_guid 1c34:da03:0007:7950 sys_image_guid 1c34:da03:0007:7953
> > 1: ibp9s0f0: node_type ca fw 2.42.5000 node_guid 1c34:da03:0007:7a60 sys_image_guid 1c34:da03:0007:7a63
> >
> > [leonro@c-235-8-1-005 ~]$ uname -a
> > Linux c-235-8-1-005 5.14.16-201.fc34.x86_64 #1 SMP Wed Nov 3 13:57:29 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux
> > [leonro@c-235-8-1-005 ~]$ rdma dev
> > 0: ibp8s0f0: node_type ca fw 2.42.5000 node_guid 1c34:da03:0007:7950 sys_image_guid 1c34:da03:0007:7953
> > 1: ibp9s0f0: node_type ca fw 2.42.5000 node_guid 1c34:da03:0007:7a60 sys_image_guid 1c34:da03:0007:7a63
> > [leonro@c-235-8-1-005 ~]$ lspci |grep nox
> > 08:00.0 Network controller: Mellanox Technologies MT27520 Family [ConnectX-3 Pro]
> > 09:00.0 Network controller: Mellanox Technologies MT27520 Family [ConnectX-3 Pro]
> >
> > Thanks
> >
> Hi,
> 
> I tried different host with CX-3/CX-5, they all work fine. and I can
> only reproduce on hosts with a bit old HCA:
> 03:00.0 InfiniBand: Mellanox Technologies MT26428 [ConnectX VPI PCIe
> 2.0 5GT/s - IB QDR / 10GigE] (rev b0)
> 
> The bug report link
> https://bugzilla.redhat.com/show_bug.cgi?id=2014094, mentioned HCA
> ConnectX too.
> 
> 01:00.0 InfiniBand [0c06]: Mellanox Technologies MT25408A0-FCC-GI
> ConnectX, Dual Port 20Gb/s InfiniBand / 10GigE Adapter IC with PCIe
> 2.0 x8 5.0GT/s In... (rev b0)
> with the instrument, I only narrow it down to
> 1438                 port = setup_port(coredev, port_num, &attr);
> 1439                 if (IS_ERR(port)) {
> 1440                         ret = PTR_ERR(port);
> 1441                         pr_info("setup ports failed %d\n", ret);
> 1442                         goto err_put;
> 1443                 }

Keep going with the tracing, there are lots of allocations in there.

> My guess is the ConnectX HCA may be missing some features, which leads
> to ENOMEM, I will continue the instrument if no other hint.

Since there is no memory allocation failure splat I'm guessing some
memory allocation hit an overflow and silently failed - ie mlx4 is
possibily setting some value to something bogus

Jason