Re: [PATCH] iommu/amd: Set translation valid bit only when IO page tables are in used

[Suravee Suthikulpanit]

On 4/20/22 6:29 PM, Suravee Suthikulpanit wrote:
> On AMD system with SNP enabled, IOMMU hardware checks the host translation
> valid (TV) and guest translation valid (GV) bits in the device
> table entry (DTE) before accessing the corresponded page tables.
>
> However, current IOMMU driver sets the TV bit for all devices
> regardless of whether the host page table is in used.
> This results in ILLEGAL_DEV_TABLE_ENTRY event for devices, which
> do not the host page table root pointer set up.
>
> Thefore, only set TV bit when host or guest page tables are in used.
>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>

I found a bug in this patch. I will send out v2 with the fix.

Regards,
Suravee