Re: [PATCH 0/2] KVM: arm64: Control visibility of S1PIE related sysregs to userspace
From: Marc Zyngier
Date: Wed Aug 21 2024 - 10:45:30 EST
On Wed, 21 Aug 2024 15:01:54 +0100,
Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> [1 <text/plain; us-ascii (7bit)>]
> On Wed, Aug 21, 2024 at 02:46:25PM +0100, Marc Zyngier wrote:
> > Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> > > Mark Brown (2):
> > > KVM: arm64: Hide TCR2_EL1 from userspace when disabled for guests
> > > KVM: arm64: Hide S1PIE registers from userspace when disabled for guests
>
> > If you are going to do this, please add it on top of [1], and handle
> > the corresponding EL2 registers.
>
> OK. To confirm, this is a desirable change?
Yes.
Ultimately, we need to revisit the way we deal with visibility, as
adding a myriad of helpers checking a combination of features doesn't
scale. That information should exist as a static table, just like the
trap bits.
But until then, that's probably the way.
M.
--
Without deviation from the norm, progress is not possible.