Date:   Mon, 6 Feb 2023 16:44:05 +0000
From:   Catalin Marinas <catalin.marinas@arm.com>
To:     Marc Zyngier <maz@kernel.org>
Cc:     Mark Brown <broonie@kernel.org>, Will Deacon <will@kernel.org>,
        Oleg Nesterov <oleg@redhat.com>,
        James Morse <james.morse@arm.com>,
        Alexandru Elisei <alexandru.elisei@arm.com>,
        Suzuki K Poulose <suzuki.poulose@arm.com>,
        Oliver Upton <oliver.upton@linux.dev>,
        Shuah Khan <shuah@kernel.org>,
        Alan Hayward <alan.hayward@arm.com>,
        Luis Machado <luis.machado@arm.com>,
        Szabolcs Nagy <szabolcs.nagy@arm.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        kvmarm@lists.linux.dev, linux-kselftest@vger.kernel.org
Subject: Re: [PATCH v4 07/21] arm64/sme: Enable host kernel to access ZT0
Message-ID: <Y+EuVbkpQJk6z+Zu@arm.com>
References: <20221208-arm64-sme2-v4-0-f2fa0aef982f@kernel.org>
 <20221208-arm64-sme2-v4-7-f2fa0aef982f@kernel.org>
 <86y1pbywbb.wl-maz@kernel.org>
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On Mon, Feb 06, 2023 at 09:31:20AM +0000, Marc Zyngier wrote:
> From a6c4aaccd33e453ffc8d8ea23a4dd4d9a263cc89 Mon Sep 17 00:00:00 2001
> From: Marc Zyngier <maz@kernel.org>
> Date: Mon, 6 Feb 2023 09:24:40 +0000
> Subject: [PATCH] arm64/sme: Fix __finalise_el2 SMEver check
> 
> When checking for ID_AA64SMFR0_EL1.SMEver, __check_override assumes
> that the ID_AA64SMFR0_EL1 value is in x1, and the intent of the code
> is to reuse value read a few lines above.
> 
> However, as the comment says at the beginning of the macro, x1 will
> be clobbered, and the checks always fails.
> 
> The easiest fix is just to reload the id register before checking it.
> 
> Fixes: f122576f3533 ("arm64/sme: Enable host kernel to access ZT0")
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Thanks Marc. I queued it on top of the for-next/sme2 branch.

-- 
Catalin