From patchwork Tue Jan 26 15:15:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 12047097 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=-17.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 8C8C8C433E0 for ; Tue, 26 Jan 2021 15:17:41 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3F1E523109 for ; Tue, 26 Jan 2021 15:17:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3F1E523109 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=JuHi8hwcN0Ur11vemIK5SsP7YHjzqq95P/kvNg3VD68=; b=iGDHb6QkXCMgecqKXhSMZxvAw VanB3MFPiuHhVQrWQeB5JGsYFJ5NIacoK3ktW3hgM4YjMMRWuONmsxpkzPgcMuxmc/qBGaCraQiK2 MjWlrE00FAkAHcungP+/5OEnsRQxN/xQ//VVa+sMwQepzcc27mHudtsZURDTwMrGCQvgj65pmIlzP Ysgr/Gw+Z7I2rTMaAIQ+dL3U8MDUGYQsRnHXTFVxsVihvuAAQVCQpMM9iykQq04zcl+itBXScWLHP Nut2wG8KwRA8h3cHTrYwwp6hlDMcWRjD2f0JnJLpU/EQZ1iCNOnGP8aMII+Yb2XnrHntHz/tHBwVT bP/tmYXFw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4Q4p-00013W-Ch; Tue, 26 Jan 2021 15:16:19 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1l4Q4g-00011c-Om for linux-arm-kernel@lists.infradead.org; Tue, 26 Jan 2021 15:16:12 +0000 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 25A7D2311B; Tue, 26 Jan 2021 15:16:10 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1l4Q4e-00A9nZ-Gu; Tue, 26 Jan 2021 15:16:08 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: [PATCH 2/2] KVM: arm64: Don't access PMSELR_EL0/PMUSERENR_EL0 when no PMU is available Date: Tue, 26 Jan 2021 15:15:21 +0000 Message-Id: <20210126151521.2958688-3-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210126151521.2958688-1-maz@kernel.org> References: <20210126151521.2958688-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, andre.przywara@arm.com, kernel-team@android.com 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-20210126_101610_887727_C9FE4343 X-CRM114-Status: GOOD ( 15.24 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andre Przywara , kernel-team@android.com, James Morse , Julien Thierry , Suzuki K Poulose Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org When running under a nesting hypervisor, it isn't guaranteed that the virtual HW will include a PMU. In which case, let's not try to access the PMU registers in the world switch, as that'd be deadly. Reported-by: Andre Przywara Signed-off-by: Marc Zyngier --- arch/arm64/kernel/image-vars.h | 3 +++ arch/arm64/kvm/hyp/include/hyp/switch.h | 9 ++++++--- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index f676243abac6..32af3c865700 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -102,6 +102,9 @@ KVM_NVHE_ALIAS(__stop___kvm_ex_table); /* Array containing bases of nVHE per-CPU memory regions. */ KVM_NVHE_ALIAS(kvm_arm_hyp_percpu_base); +/* PMU available static key */ +KVM_NVHE_ALIAS(kvm_arm_pmu_available); + #endif /* CONFIG_KVM */ #endif /* __ARM64_KERNEL_IMAGE_VARS_H */ diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 84473574c2e7..75c0faa3b791 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -90,15 +90,18 @@ static inline void __activate_traps_common(struct kvm_vcpu *vcpu) * counter, which could make a PMXEVCNTR_EL0 access UNDEF at * EL1 instead of being trapped to EL2. */ - write_sysreg(0, pmselr_el0); - write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); + if (kvm_arm_support_pmu_v3()) { + write_sysreg(0, pmselr_el0); + write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); + } write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2); } static inline void __deactivate_traps_common(void) { write_sysreg(0, hstr_el2); - write_sysreg(0, pmuserenr_el0); + if (kvm_arm_support_pmu_v3()) + write_sysreg(0, pmuserenr_el0); } static inline void ___activate_traps(struct kvm_vcpu *vcpu)