From nobody Wed Dec 17 03:02:16 2025 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DE7765103C for ; Tue, 18 Jun 2024 06:38:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718692706; cv=none; b=UH434LnkL+W3PhKyUesOu2XK4vhLTrNbEUNsvpwJ3ZAUrhxWwCumQU8cVeQnpUgRY2Hv3K4/5jScnfhJx60KHkf66qmI57C06AjGN2t1MJw+JK2F3MlKA0Ax2Ky1zpRufRIa7sxhSNWjCxJyeHpS+5YeBSMpqw9y2nuk/oWZiyc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718692706; c=relaxed/simple; bh=gr/1SwPJAVw0cJI2ym1vviBSRlIVKgVhxz//Y+b5Aok=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=SLQwHWoU/C2TJKPPxaCY5bbe/+P1EiOCnWX5iQxl0bnkBjEHhJ4LtMXNs/FW/DB18ZNOzEDAmfrHM6eMx9jq6m7y0U6A9M45z0ejuxiT1OtBcjVzr4hPy/mbPtS/Ac+Di82zX4jut3S2hmNB2jfLNCFpWnjH8yLVBP0lxzq3gcQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=bAzviyU2; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="bAzviyU2" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1718692704; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=alVkXy29B6lCCtrvfQsOKPf61sX9EkJJRVUtXFrupoY=; b=bAzviyU2jbwkIPDodNA/IRSxspStzXPhlXVzYvnTJeGFeqAJeLLnFwGz/6+rrCj4mERaYv 0zAA8DtXzUDcwn5PjC+mqUupI2wSIVn1nDmYRMUUMFHwBNcNHoQ6zJ+Z+q7imQ18XXfgjM ErMomVzYVfFO/Cxa1u//txiaxViBvLI= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-467-H7SqDQxRMM23ukg-vVGD_g-1; Tue, 18 Jun 2024 02:38:19 -0400 X-MC-Unique: H7SqDQxRMM23ukg-vVGD_g-1 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 671A919560B0; Tue, 18 Jun 2024 06:38:17 +0000 (UTC) Received: from virt-mtcollins-01.lab.eng.rdu2.redhat.com (virt-mtcollins-01.lab.eng.rdu2.redhat.com [10.8.1.196]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id A4F811956055; Tue, 18 Jun 2024 06:38:14 +0000 (UTC) From: Shaoqin Huang To: Oliver Upton , Marc Zyngier , kvmarm@lists.linux.dev Cc: Shaoqin Huang , James Morse , Suzuki K Poulose , Zenghui Yu , Catalin Marinas , Will Deacon , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 1/2] KVM: arm64: Allow userspace to change ID_AA64PFR1_EL1 Date: Tue, 18 Jun 2024 02:38:06 -0400 Message-Id: <20240618063808.1040085-2-shahuang@redhat.com> In-Reply-To: <20240618063808.1040085-1-shahuang@redhat.com> References: <20240618063808.1040085-1-shahuang@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Content-Type: text/plain; charset="utf-8" Allow userspace to change the guest-visible value of the register with some severe limitation: - No changes to features not virtualized by KVM (MPAM_frac, RAS_frac) --- arch/arm64/kvm/sys_regs.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 22b45a15d068..bead81867bce 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -2306,7 +2306,8 @@ static const struct sys_reg_desc sys_reg_descs[] =3D { ID_AA64PFR0_EL1_GIC | ID_AA64PFR0_EL1_AdvSIMD | ID_AA64PFR0_EL1_FP), }, - ID_SANITISED(ID_AA64PFR1_EL1), + ID_WRITABLE(ID_AA64PFR1_EL1, ~(ID_AA64PFR1_EL1_RAS_frac | + ID_AA64PFR1_EL1_MPAM_frac)), ID_UNALLOCATED(4,2), ID_UNALLOCATED(4,3), ID_WRITABLE(ID_AA64ZFR0_EL1, ~ID_AA64ZFR0_EL1_RES0), --=20 2.40.1