Date: Wed, 07 Feb 2024 10:57:26 +0000
Message-ID: <86plx85yp5.wl-maz@kernel.org>
From: Marc Zyngier <maz@kernel.org>
To: Oliver Upton <oliver.upton@linux.dev>
Cc: kvmarm@lists.linux.dev,
	linux-arm-kernel@lists.infradead.org,
	James Morse <james.morse@arm.com>,
	Suzuki K Poulose <suzuki.poulose@arm.com>,
	Zenghui Yu <yuzenghui@huawei.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	Will Deacon <will@kernel.org>,
	Joey Gouly <joey.gouly@arm.com>,
	Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH v3 04/26] KVM: arm64: nv: Add sanitising to EL2 configuration registers
In-Reply-To: <ZcNeCACYeozbM_Dr@linux.dev>
References: <20240205103431.1104133-1-maz@kernel.org>
	<20240205103431.1104133-5-maz@kernel.org>
	<ZcNeCACYeozbM_Dr@linux.dev>
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On Wed, 07 Feb 2024 10:40:08 +0000,
Oliver Upton <oliver.upton@linux.dev> wrote:
> 
> On Mon, Feb 05, 2024 at 10:34:09AM +0000, Marc Zyngier wrote:
> > +	if (!(__vcpu_has_feature(&kvm->arch, KVM_ARM_VCPU_PTRAUTH_ADDRESS) &&
> > +	      __vcpu_has_feature(&kvm->arch, KVM_ARM_VCPU_PTRAUTH_ADDRESS)))
> > +		res0 |= (HCR_API | HCR_APK);
> 
> I think what you probably meant here is _ADDRESS and _GENERIC, right? Of
> course, this has no actual effect on the code, since we don't allow one
> without the other.

Gah. Embarrassing. But yes, harmless as we set both bits all the time.

> Maybe we can just change KVM's representation to a single flag to avoid
> this pointless exercise.

Yeah, it's been on my list of things to cleanup for a while. I'll look
into it for a separate patch.

Thanks,

	M.

-- 
Without deviation from the norm, progress is not possible.