Re: [PATCH v4 27/34] KVM: arm64: Always zero invalid PTEs

From: Will Deacon
Date: Thu Mar 11 2021 - 12:34:26 EST


On Wed, Mar 10, 2021 at 05:57:44PM +0000, Quentin Perret wrote:
> kvm_set_invalid_pte() currently only clears bit 0 from a PTE because
> stage2_map_walk_table_post() needs to be able to follow the anchor. In
> preparation for re-using bits 63-02 from invalid PTEs, make sure to zero

Why do you exclude bit 1 from this range?

> it entirely by ensuring to cache the anchor's child upfront.
>
> Suggested-by: Will Deacon <will@xxxxxxxxxx>
> Signed-off-by: Quentin Perret <qperret@xxxxxxxxxx>
> ---
> arch/arm64/kvm/hyp/pgtable.c | 26 ++++++++++++++++----------
> 1 file changed, 16 insertions(+), 10 deletions(-)

For the patch:

Acked-by: Will Deacon <will@xxxxxxxxxx>

Will