From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7312C3F2D1 for ; Mon, 2 Mar 2020 18:18:05 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 8B9C62465E for ; Mon, 2 Mar 2020 18:18:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8B9C62465E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4714D4AEE1; Mon, 2 Mar 2020 13:18:05 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 9ShIAx79fVPs; Mon, 2 Mar 2020 13:18:04 -0500 (EST) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 1F5184AF26; Mon, 2 Mar 2020 13:18:04 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 010134AF20 for ; Mon, 2 Mar 2020 13:18:03 -0500 (EST) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id aPQuqD46pmKu for ; Mon, 2 Mar 2020 13:18:01 -0500 (EST) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 9F7ED4AF14 for ; Mon, 2 Mar 2020 13:18:01 -0500 (EST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 637F91045; Mon, 2 Mar 2020 10:18:01 -0800 (PST) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 7F1D53F6C4; Mon, 2 Mar 2020 10:18:00 -0800 (PST) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Subject: [PATCHv6 2/3] KVM: arm64: limit PMU version to PMUv3 for ARMv8.1 Date: Mon, 2 Mar 2020 18:17:51 +0000 Message-Id: <20200302181752.14251-3-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20200302181752.14251-1-mark.rutland@arm.com> References: <20200302181752.14251-1-mark.rutland@arm.com> Cc: catalin.marinas@arm.com, will@kernel.org, kvmarm@lists.cs.columbia.edu, maz@kernel.org X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu From: Andrew Murray We currently expose the PMU version of the host to the guest via emulation of the DFR0_EL1 and AA64DFR0_EL1 debug feature registers. However many of the features offered beyond PMUv3 for 8.1 are not supported in KVM. Examples of this include support for the PMMIR registers (added in PMUv3 for ARMv8.4) and 64-bit event counters added in (PMUv3 for ARMv8.5). Let's trap the Debug Feature Registers in order to limit PMUVer/PerfMon in the Debug Feature Registers to PMUv3 for ARMv8.1 to avoid unexpected behaviour. Both ID_AA64DFR0.PMUVer and ID_DFR0.PerfMon follow the "Alternative ID scheme used for the Performance Monitors Extension version" where 0xF means an IMPLEMENTATION DEFINED PMU is implemented, and values 0x0-0xE are treated as with an unsigned field (with 0x0 meaning no PMU is present). As we don't expect to expose an IMPLEMENTATION DEFINED PMU, and our cap is below 0xF, we can treat these fields as unsigned when applying the cap. Signed-off-by: Andrew Murray Reviewed-by: Suzuki K Poulose [Mark: make field names consistent, use perfmon cap] Signed-off-by: Mark Rutland --- arch/arm64/include/asm/sysreg.h | 6 ++++++ arch/arm64/kvm/sys_regs.c | 10 ++++++++++ 2 files changed, 16 insertions(+) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index b91570ff9db1..d8f1eed070f0 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -702,6 +702,12 @@ #define ID_AA64DFR0_TRACEVER_SHIFT 4 #define ID_AA64DFR0_DEBUGVER_SHIFT 0 +#define ID_AA64DFR0_PMUVER_8_1 0x4 + +#define ID_DFR0_PERFMON_SHIFT 24 + +#define ID_DFR0_PERFMON_8_1 0x4 + #define ID_ISAR5_RDM_SHIFT 24 #define ID_ISAR5_CRC32_SHIFT 16 #define ID_ISAR5_SHA2_SHIFT 12 diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 3e909b117f0c..b0a3e8976b90 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1085,6 +1085,16 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, (0xfUL << ID_AA64ISAR1_API_SHIFT) | (0xfUL << ID_AA64ISAR1_GPA_SHIFT) | (0xfUL << ID_AA64ISAR1_GPI_SHIFT)); + } else if (id == SYS_ID_AA64DFR0_EL1) { + /* Limit guests to PMUv3 for ARMv8.1 */ + val = cpuid_feature_cap_perfmon_field(val, + ID_AA64DFR0_PMUVER_SHIFT, + ID_AA64DFR0_PMUVER_8_1); + } else if (id == SYS_ID_DFR0_EL1) { + /* Limit guests to PMUv3 for ARMv8.1 */ + val = cpuid_feature_cap_perfmon_field(val, + ID_DFR0_PERFMON_SHIFT, + ID_DFR0_PERFMON_8_1); } return val; -- 2.11.0 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm