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Date:   Mon, 17 Jan 2022 16:57:19 +0000
From:   "Russell King (Oracle)" <linux@armlinux.org.uk>
To:     Marc Zyngier <maz@kernel.org>
Cc:     linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu,
        kvm@vger.kernel.org, Andre Przywara <andre.przywara@arm.com>,
        Christoffer Dall <christoffer.dall@arm.com>,
        Jintack Lim <jintack@cs.columbia.edu>,
        Haibo Xu <haibo.xu@linaro.org>,
        Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com>,
        James Morse <james.morse@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        kernel-team@android.com
Subject: Re: [PATCH v5 07/69] KVM: arm64: nv: Introduce nested virtualization
 VCPU feature
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References: <20211129200150.351436-1-maz@kernel.org>
 <20211129200150.351436-8-maz@kernel.org>
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On Mon, Nov 29, 2021 at 08:00:48PM +0000, Marc Zyngier wrote:
> From: Christoffer Dall <christoffer.dall@arm.com>
> 
> Introduce the feature bit and a primitive that checks if the feature is
> set behind a static key check based on the cpus_have_const_cap check.
> 
> Checking nested_virt_in_use() on systems without nested virt enabled
> should have neglgible overhead.
> 
> We don't yet allow userspace to actually set this feature.
> 
> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>

-- 
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