Re: [dpdk-users] DPDK on Mellanox BlueField Ref Platform

["Jim Vaigl" <jimv@rockbridgesoftware.com>]

On Tue, 24 Sep 2019 12:31:51 -0400
"Jim Vaigl" <jimv@rockbridgesoftware.com> wrote:

>> Since no one has chimed in with any build/install/configure suggestion
for
>> the
>> BlueField, I've spent some time debugging and thought I'd share the
results.
>> Building the l3fwd example application and running it as the docs
suggest,
>> when
>> I try to send it UDP packets from another machine, it dumps core.
>> 
>> Debugging a bit with gdb and printf, I can see that from inside
>> process_packet()
>> and processx4_step1() the calls to rte_pktmbuf_mtod() return Nil or
>> suspicious
>> pointer values (i.e. 0x80).  The sample apps don't guard against NULL
>> pointers
>> being returned from this rte call, so that's why it's dumping core.
>> 
>> I still think the problem is related to the driver config, but thought
this
>> might ring a bell for anyone who's had problems like this.
>> 
>> The thing that still bothers me is that rather than seeing what I was
>> expecting
>> at init based on what the documentation shows:
>>     [...]
>>     EAL: probe driver: 15b3:1013 librte_pmd_mlx5
>> 
>> ... when rte_eal_init() runs, I'm seeing:
>>     [...]
>>     EAL:  Selected IOVA mode 'PA'
>>     EAL:  Probing VFIO support...
>> 
>> This still seems wrong, and I've verified that specifying the BlueField
>> target ID
>> string in the make is causing "CONFIG_RTE_LIBRTE_MLX5_PMD=y" to appear in
>> the .config.
>> 
>> Regards,
>> --Jim Vaigl
>> 614 886 5999
>> 
>> 
>
>From: Stephen Hemminger [mailto:stephen@networkplumber.org] 
>Sent: Tuesday, September 24, 2019 1:18 PM
>To: Jim Vaigl
>Cc: users@dpdk.org
>
>Subject: Re: [dpdk-users] DPDK on Mellanox BlueField Ref Platform
>make sure you have latest version of rdma-core installed (v25).
>The right version is not in most distros

Great suggestion.  I'm using the rdma-core from the MLNX_OFED 4.6-3.5.8.0
install.  I can't figure out how to tell what version that thing includes,
even looking at the source, since there's no version information in the
source files, BUT I went to github and downloaded rdma-core v24 and v25
and neither diff cleanly with the source RPM that comes in the OFED
install.  I don't know yet if it's because this is some different version
or if it's because Mellanox has made their own tweaks.

I would hope that the very latest OFED from Mellanox would include an
up-to-date and working set of libs/modules, but maybe you're on to
something.  It sounds like a risky move, but maybe I'll try just
installing rdma-core from github over top of the OFED install.  I have a
fear that I'll end up with inconsistent versions, but it's worth a try.

Thanks,
--Jim