[dpdk-users] net/axgbe pmd and vfio-pci

[Aveer Jain <aveerj@gmail.com>]

Hi,



I am trying to migrate to poll-mode-driver on an AMD system, and couldn’t
get the link up until I use igb_uio module in legacy mode
(intr_mode=legacy) as suggested by the release note 7.5 in dpdk (ref:
IXA00378191
https://dpdk.readthedocs.io/en/v1.8.0/rel_notes/resolved_issues.html)

But one thing is not clear to me, the nic capabilities list MSI-x support
as well as in dmesg I see MSI-X support is enabled, then ideally, I should
not see any issue in using vfio-pci module.



Is it that the current axgbe user-space driver doesn’t support the embedded
AMD ethernet devices in my system or dpdk pmd infrastructure is expecting
something enabled/disabled on my system for it to make use of vfio-pci
driver.



Don’t want to pack too many issues in one thread, but with igb_uio driver
links come up and forwarding works fine but eal_intr_thread consumes 100%
CPU and number of interrupts for igb_uio driver are huge, so either axgbe
driver is not clearing interrupt or nic is generating interrupts at crazy
rate. Is some issue like this known with igb_uio running in
intr_mode=legacy? I am suspecting it to be an issue with igb_uio because I
gave a try it on Intel 82599 nics, there link doesn’t work with latest
mainline kernel (5.0) but works with kernel 4.4.



I am sure people would have used vfio-pci with AMD ethernet devices
successfully (Advanced Micro Devices, Inc. [AMD] Device 1458).



CPU: AMD Ryzen Embedded

Running on kernel 4.19

Distro: centos

Dpdk: 19.02



Thanks,

Aveer