Re: [dpdk-dev] Please revert mlx IOVA VA mode patch

[Yongseok Koh <yskoh@mellanox.com>]

We'll have to look into the issue.
It doesn't seem simple though.
Thomas, can you please revert the patch from the master?


Thanks,
Yongseok

> On Jun 7, 2019, at 11:33 AM, Stephen Hemminger <stephen@networkplumber.org> wrote:
> 
> The Netvsc PMD got broken on DPDK 19.08 by a bad patch in Mellanox driver.
> On a simple setup with SRIOV enabled and using netvsc PMD with the testpmd.
> It worked in 19.05 and does not work with current master.
> 
> The probe code gets stuck because netvsc PMD sends a request to host
> and never sees a response.
> 
> # ./build/app/testpmd --log-level='pmd.net.netvsc.*:debug' -l 0-3 -n 4  -- --rxq=4 --txq=4 -i
> EAL: Detected 4 lcore(s)
> EAL: Detected 1 NUMA nodes
> EAL: Multi-process socket /var/run/dpdk/rte/mp_socket
> EAL: Probing VFIO support...
> EAL: WARNING: cpu flags constant_tsc=yes nonstop_tsc=no -> using unreliable clock cycles !
> EAL: PCI device 935f:00:02.0 on NUMA socket 0
> EAL:   probe driver: 15b3:1014 net_mlx5
> net_mlx5: can not get IB device "mlx5_0" ports number
> eth_hn_probe():  >>
> eth_hn_dev_init():  >>
> hn_nvs_init(): NVS version 0x60001, NDIS version 6.30
> hn_nvs_conn_rxbuf(): connect rxbuff va=0x2200402000 gpad=0xe1e2d
> hn_nvs_conn_rxbuf(): receive buffer size 1728 count 18811
> hn_nvs_conn_chim(): connect send buf va=0x2202302000 gpad=0xe1e2e
> hn_nvs_conn_chim(): send buffer 16777216 section size:6144, count:2730
> (hung)
> 
> The problem does not occur without SRIOV (or if MLX driver is not
> compiled in).
> 
> Doing bisect the problem is caused by:
> 
> commit 69c06d0e357ed0064b498d510d169603cf7308cd
> Author: Yongseok Koh <yskoh@mellanox.com>
> Date:   Thu May 2 02:07:54 2019 -0700
> 
>    net/mlx: support IOVA VA mode
> 
>    Set RTE_PCI_DRV_IOVA_AS_VA to driver's drv_flags as device's IOMMU takes
>    virtual address.
> 
>    Cc: stable@dpdk.org
> 
>    Signed-off-by: Yongseok Koh <yskoh@mellanox.com>
>    Acked-by: Shahaf Shuler <shahafs@mellanox.com>
> 
> Please either revert or fix this patch ASAP.
>