[dpdk-dev] [PATCH] net/mlx5: fix UAR memory mapping type

[Ori Kam]

> -----Original Message-----
> From: dev <dev-bounces at dpdk.org> On Behalf Of Viacheslav Ovsiienko
> 
> The User Access Region is a special mechanism to provide direct
> access to the hardware registers, and is the part of PCI address
> space that is mapped to CPU virtual address. The mapping can be
> performed with the type "Write-Combining" or "Non-Cached", and
> these ones might be supported or not on different setups.
> 
> To prevent device probing failure the UAR allocation attempt
> with alternative mapping type is performed. The datapath
> takes the actual UAR mapping into account on queue creation.
> 
> There was another issue with NULL UAR base address.
> OFED 5.0.x and Upstream rdma_core before v29 returned the NULL as
> UAR base address if UAR was not the first object in the UAR page.
> It caused the PMD failure and we should try to get another UAR
> till we get the first one with non-NULL base address returned.
> 
> Fixes: fc4d4f732bbc ("net/mlx5: introduce shared UAR resource")
> 
> Signed-off-by: Viacheslav Ovsiienko <viacheslavo at mellanox.com>
> ---
> --
> 1.8.3.1

Acked-by: Ori Kam <orika at mellanox.com>
Thanks,
Ori