Re: [PATCH v2] vdpa/mlx5: workaround var offset within page

[Maxime Coquelin <maxime.coquelin@redhat.com>]

Hi Yajun,

On 3/15/22 03:47, Yajun Wu wrote:
> vDPA driver first uses kernel driver to allocate doorbell(VAR) area for
> each device. Then uses var->mmap_off and var->length to mmap uverbs device
> file as doorbell userspace virtual address.
> 
> Current kernel driver provides var->mmap_off equal to page start of VAR.
> It's fine with x86 4K page server, because VAR physical address is only 4K
> aligned thus locate in 4K page start.
> 
> But with aarch64 64K page server, the actual VAR physical address has
> offset within page(not locate in 64K page start). So vDPA driver need add
> this within page offset(caps.doorbell_bar_offset) to get right VAR virtual
> address.
> 
> Fixes: 62c813706e4 ("vdpa/mlx5: map doorbell")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Yajun Wu <yajunw@nvidia.com>
> Acked-by: Matan Azrad <matan@nvidia.com>
> ---
>   drivers/vdpa/mlx5/mlx5_vdpa_virtq.c | 9 ++++++++-
>   1 file changed, 8 insertions(+), 1 deletion(-)
> 

Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime