Re: [PATCH v2 1/8] iommu/vt-d: Use non-privileged mode for all PASIDs

[Baolu Lu]

On 3/28/23 7:21 AM, Jacob Pan wrote:
> Supervisor Request Enable (SRE) bit in a PASID entry is for permission
> checking on DMA requests. When SRE = 0, DMA with supervisor privilege
> will be blocked. However, for in-kernel DMA this is not necessary in that
> we are targeting kernel memory anyway. There's no need to differentiate
> user and kernel for in-kernel DMA.
>
> Let's use non-privileged (user) permission for all PASIDs used in kernel,
> it will be consistent with DMA without PASID (RID_PASID) as well.
>
> Signed-off-by: Jacob Pan<jacob.jun.pan@xxxxxxxxxxxxxxx>

Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>

Best regards,
baolu