From patchwork Tue Aug 20 13:18:02 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13770101 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9B993C531DF for ; Tue, 20 Aug 2024 13:25:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=htwYBIdpOpKXaxCJBMhyE7UJLM4kElXHsxFi1QbZCno=; b=ogpf4zwew43bNcBguq5bN+ncyD mtxInaARne39omzrHt9fcVmYMwmxw027w0IW6bXSgc3e2zKwmLime7j8qWem5I6Uj8PUyYbrfLJFl azj0gCW8KCfJycHklKWpBwZzRGvYdbmFx98cWGK93SrxuhBITtctM1dYhB6W4kY0Bme5yWuHNprbI qN9yOphkR4QME8EnONKcPxaDAedTCm6D59Xu3Ysn5KnCMoO7za+d5+T0O1QSDJkT/qmjRTv/LIFRn f3x49i1WlmLPinEBukPZXmkXMG6gELtAiYNp8ZshmcJY2rIGW6b9slfur1kxCThgJClyRHB7HGZcS ZSzCMkVQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgOrM-00000005LY7-0lRU; Tue, 20 Aug 2024 13:25:16 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgOkV-00000005Jj0-1aD9 for linux-arm-kernel@lists.infradead.org; Tue, 20 Aug 2024 13:18:13 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id D765760DF2; Tue, 20 Aug 2024 13:18:09 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A77A2C4AF0C; Tue, 20 Aug 2024 13:18:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724159889; bh=cFqreJ/QbxIcyFcklwuEN/SmjI5Xc8eDvAlus4TNHLI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KgwyPb05YoSan4ON9gfuNdapsHaPM9npzM3H0ZH/m4O3KRnEyoadshkDtB233ebIR l8V7iQC8GkUeYUCnbJ/x00WH1UH0qhlfoyGn2pSbQz6vTZRgb0+U/WpCMfb90TdY74 s4enKzKZsyx379Sg9G8wFo80Zp9Y405/VkTj6FQjpRkn+Q41YWpSk6AUuk6JWAzH1+ CN5ArTvsAtQGA6P1SdbY9OvtutMj9psdlP64RYs/80c+OEaIvYA3HSuvuI3cUYOzeb X+ZNOyhLWsega/HYmQu3vOu2ZwFlGJnbJMEVBTrfUbJUAc2h906YLJ5rL+oF8F6ouc sDGyG6V9ZOVDQ== 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 4.95) (envelope-from ) id 1sgOkR-005HMQ-Jr; Tue, 20 Aug 2024 14:18:07 +0100 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Joey Gouly , Mark Brown Subject: [PATCH v4 8/8] KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests Date: Tue, 20 Aug 2024 14:18:02 +0100 Message-Id: <20240820131802.3547589-9-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240820131802.3547589-1-maz@kernel.org> References: <20240820131802.3547589-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, tabba@google.com, joey.gouly@arm.com, broonie@kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240820_061811_549038_CD3AF1C2 X-CRM114-Status: GOOD ( 12.17 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Everything is now in place for a guest to "enjoy" FP8 support. Expose ID_AA64PFR2_EL1 to both userspace and guests, with the explicit restriction of only being able to clear FPMR. All other features (MTE* at the time of writing) are hidden and not writable. Signed-off-by: Marc Zyngier --- arch/arm64/kvm/sys_regs.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 51627add0a72..2d1e45178422 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1539,6 +1539,10 @@ static u64 __kvm_read_sanitised_id_reg(const struct kvm_vcpu *vcpu, val &= ~ARM64_FEATURE_MASK(ID_AA64PFR1_EL1_SME); break; + case SYS_ID_AA64PFR2_EL1: + /* We only expose FPMR */ + val &= ID_AA64PFR2_EL1_FPMR; + break; case SYS_ID_AA64ISAR1_EL1: if (!vcpu_has_ptrauth(vcpu)) val &= ~(ARM64_FEATURE_MASK(ID_AA64ISAR1_EL1_APA) | @@ -2381,7 +2385,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { ID_AA64PFR0_EL1_AdvSIMD | ID_AA64PFR0_EL1_FP), }, ID_SANITISED(ID_AA64PFR1_EL1), - ID_UNALLOCATED(4,2), + ID_WRITABLE(ID_AA64PFR2_EL1, ID_AA64PFR2_EL1_FPMR), ID_UNALLOCATED(4,3), ID_WRITABLE(ID_AA64ZFR0_EL1, ~ID_AA64ZFR0_EL1_RES0), ID_HIDDEN(ID_AA64SMFR0_EL1),