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From: Mark Brown <broonie@kernel.org>
To: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] arm64: Document boot requirements for FEAT_SME_FA64
Date: Tue, 26 Oct 2021 11:33:33 +0100	[thread overview]
Message-ID: <YXfZfe9vuSLXfN6O@sirena.org.uk> (raw)
In-Reply-To: <20211026092925.GB21289@willie-the-truck>


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On Tue, Oct 26, 2021 at 10:29:25AM +0100, Will Deacon wrote:
> On Mon, Oct 25, 2021 at 01:48:22PM +0100, Mark Brown wrote:

> > + - If the kernel is entered at EL1 and EL2 is present:
> > +
> > +    - SMCR_EL2.FA64 (bit 31) must be initialised to to 0b1.

> With the second bullet, does that mean KVM is in violation of our own
> documentation?

No worse than it was before - we already document the requirements for
baseline SME which we don't ourselves satisfy, no guest will be able to
get as far as noticing that FA64 isn't enabled since all SME operations
will trap.

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      reply	other threads:[~2021-10-26 10:34 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-25 12:48 [PATCH] arm64: Document boot requirements for FEAT_SME_FA64 Mark Brown
2021-10-26  9:29 ` Will Deacon
2021-10-26 10:33   ` Mark Brown [this message]

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