From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793002991; b=Av0KOXHGAfKGAsb/9zIh/BCcVI4Jk1MCDL68Ld3y26HONahIm95kdNRg3VEGHhpnND7x QvhKJMiH8/w/lwZBkDoZSaixKCC1wNw+XzucYB0yLtgdn3pAYWaNWHRyZWjEgSl0XKeJP zbRPYc6/lpZbmTXJmB1fbmUbNxhLTxZMEIM749qFpHKgYMxQo+xZlIi+o7Hi1oRqtJPa1 fweYicTZ15B/DvpkbJeF/ZxSPgqP/ic+ry1rW+5UaEy1lL+y7JZY9y5j50VqSHnRsQ0nr NQ1f7YRC1xR8gBfqgE9sOGZkvG4at/bfzjNTtE5WMj7XlYLKJ+GCEH9XIuERw6RIAtA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793002991; h=Received:DKIM-Signature:Received:From:To:Cc:Subject:Date:Message-ID: X-Mailer:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding:X-SA-Exim-Connect-IP:X-SA-Exim-Rcpt-To: X-SA-Exim-Mail-From:X-SA-Exim-Scanned; bh=iaCdCVyt1C7egWZ6jI8Y0J3eVgASMFjDhFgq4khrhao=; b=l3aosQR/Gth4x3BkHziWjfYSFCgoIq5msMTnTgEocQYMlwdO8MrOi4MMtVAhZ1VtiFyz GrE6X5RV8jyhXbVneFBphSR2QYvpluN1M+zgilSjuCUEVUlh3gGR2vHxYxHsqK5uaS0+H 6+of0BHadatrL5XamqFhcJt+BIEtJnS21+hYqg4wsG+s7+KzCsxGl68loUNhJ65JzN8oD A2vC/tsscXknHC5lUJvXf2MEVtnFoXKoUrGzekz7TO9xTkfv2oFGmFnNp3qNltP3TlP+P bCGEMRSlUnLw10FXApQA6WroCTPxuKOdWwQvZPzE4+aQDTWGgQaxs84Hda2jwZU3gmA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=D0mujMOQ; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5675C606A31B for ; Mon, 26 Oct 2026 08:23:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=D0mujMOQ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1496A1F031E2; Mon, 26 Oct 2026 08:23:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793002991; bh=iaCdCVyt1C7egWZ6jI8Y0J3eVgASMFjDhFgq4khrhao=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=D0mujMOQvxaakhh5DiXKDIQkG60Tnho4R78TJjGDJj/hVjKK6za+eim4Yz1RQ1306 N0bUuIm3HpxA3AkavvniuvVNgJHF3X5tgGL1/78fVzXU49yVURcdoM7Cm+5v7TtEY9 Ayx5V+3duCxEXAxyPhPeQaPN482cTXsRMPMsh0YkCDbi42/uTIjqf73r6cOdF+AzaN OAUdaTtO/5jdCOJdoDCuitb/5xTcCOjQ9aWojn9NYzhU87i4JDzbLLShWa9eyluGxS 9JRV5ZPzd/aWptPW9jrXPzqEMUSV12ALQDwwoja30ilmw8S/z+0saz0aX6aV8bZisW Pr0qEeUAhilGw== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1xLFz3-00000007A40-1Ich; Mon, 26 Oct 2026 08:23:09 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: Steffen Eiden , Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Catalin Marinas , Will Deacon , Mark Rutland Subject: [PATCH 2/2] KVM: arm64: Reenable MTE tag checking on exit from guest when running VHE Date: Mon, 26 Oct 2026 08:23:05 +0000 Message-ID: <20261026082305.2515705-3-maz@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261026082305.2515705-1-maz@kernel.org> References: <20261026082305.2515705-1-maz@kernel.org> X-Mailing-List: kvmarm@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, seiden@linux.ibm.com, joey.gouly@arm.com, suzuki.poulose@arm.com, oupton@kernel.org, yuzenghui@huawei.com, fuad.tabba@linux.dev, catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Once we're back from running a guest, it is important to set TCO to zero so that MTE is functional again. Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/vhe/switch.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index 4c965f9b1e1de..73c2dd61e6c69 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -193,6 +193,13 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu) if (!arm64_kernel_unmapped_at_el0()) host_vectors = __this_cpu_read(this_cpu_vector); write_sysreg(host_vectors, vbar_el1); + + /* + * We're now able to take MTE exceptions, make sure the VBAR_EL2 is + * set to the correct value. + */ + if (mte_disable_tco_entry(current)) + isb(); } NOKPROBE_SYMBOL(__deactivate_traps); -- 2.47.3