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Date:   Thu, 11 Mar 2021 17:33:38 +0000
From:   Will Deacon <will@kernel.org>
To:     Quentin Perret <qperret@google.com>
Cc:     catalin.marinas@arm.com, maz@kernel.org, james.morse@arm.com,
        julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com,
        android-kvm@google.com, linux-kernel@vger.kernel.org,
        kernel-team@android.com, kvmarm@lists.cs.columbia.edu,
        linux-arm-kernel@lists.infradead.org, tabba@google.com,
        mark.rutland@arm.com, dbrazdil@google.com, mate.toth-pal@arm.com,
        seanjc@google.com, robh+dt@kernel.org, ardb@kernel.org
Subject: Re: [PATCH v4 27/34] KVM: arm64: Always zero invalid PTEs
Message-ID: <20210311173338.GB31378@willie-the-truck>
References: <20210310175751.3320106-1-qperret@google.com>
 <20210310175751.3320106-28-qperret@google.com>
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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@kernel.org>
> Signed-off-by: Quentin Perret <qperret@google.com>
> ---
>  arch/arm64/kvm/hyp/pgtable.c | 26 ++++++++++++++++----------
>  1 file changed, 16 insertions(+), 10 deletions(-)

For the patch:

Acked-by: Will Deacon <will@kernel.org>

Will