Re: [PATCH v11 2/3] xen/arm64: io: Handle the abort due to access to stage1 translation table

[Julien Grall <julien@xxxxxxx>]

Hi Ayan,

On 17/03/2022 14:00, Ayan Kumar Halder wrote:
> If the abort was caused due to access to stage1 translation table, Xen
> will try to set the p2m entry (assuming that the Stage 1 translation
> table is in a non MMIO region).
> If there is no such entry found, then Xen will try to map the address as
> a MMIO region (assuming that the Stage 1 translation table is in a
> direct MMIO region).
>
> If that fails as well, then there are the two following scenarios:-
> 1. Stage 1 translation table being in an emulated MMIO region - Xen
> can read the region, but it has no way to return the value read to the
> CPU page table walker (which tries to go through the stage1 tables to
> resolve the translation fault).
>
> 2. Stage 1 translation table address is invalid.
>
> In both the above scenarios, Xen will forward the abort to the guest.
>
> Signed-off-by: Ayan Kumar Halder <ayankuma@xxxxxxxxxx>
Reviewed-by: Julien Grall <jgrall@xxxxxxxxxx>

Cheers,

--
Julien Grall