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=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 0C6D4C07E9B for ; Sun, 4 Jul 2021 23:07:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ECE5A611ED for ; Sun, 4 Jul 2021 23:07:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231713AbhGDXJk (ORCPT ); Sun, 4 Jul 2021 19:09:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:47610 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231183AbhGDXIa (ORCPT ); Sun, 4 Jul 2021 19:08:30 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 9312C613E5; Sun, 4 Jul 2021 23:05:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625439953; bh=k4A9U8XSbpXM50WX2bk9eqfV52wvOpVIiCKt8c8gujg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cl1I3TZ+YCF35Hj97tff50OR/Mk/k0GPy7geJPMbSRSbDkhSz27sXrsjKV+KIHIjn XWf1455SC5Wy16O395mmQfArVKQ6y3kd5WIrhPgCHa1+zml2pMtIVvhXpQoKrKSpYK J4MZgZBLBjWaOlTvOhf/XliSYkmtjgpH7jRoHNz7FAWaDzl8N+ekkhi7LAy2ypArtT 0wIcQG3qvs9Hsbj8Q7UVBLH4z9QBgVQE2r4gnr0XvHbo+XNE7LdKO+82bGKOcvZv8Q Nh8osPu9xEWL/9IBf3lbcFCSryeMBxYgL8GQ15DnTAuwhTZmCok/JMrk5KBkCVAPbF 84xu36m3Nejfw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Marc Zyngier , Jinank Jain , Sasha Levin , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Subject: [PATCH AUTOSEL 5.13 68/85] KVM: arm64: Restore PMU configuration on first run Date: Sun, 4 Jul 2021 19:04:03 -0400 Message-Id: <20210704230420.1488358-68-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210704230420.1488358-1-sashal@kernel.org> References: <20210704230420.1488358-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Marc Zyngier [ Upstream commit d0c94c49792cf780cbfefe29f81bb8c3b73bc76b ] Restoring a guest with an active virtual PMU results in no perf counters being instanciated on the host side. Not quite what you'd expect from a restore. In order to fix this, force a writeback of PMCR_EL0 on the first run of a vcpu (using a new request so that it happens once the vcpu has been loaded). This will in turn create all the host-side counters that were missing. Reported-by: Jinank Jain Tested-by: Jinank Jain Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/87wnrbylxv.wl-maz@kernel.org Link: https://lore.kernel.org/r/b53dfcf9bbc4db7f96154b1cd5188d72b9766358.camel@amazon.de Signed-off-by: Sasha Levin --- arch/arm64/include/asm/kvm_host.h | 1 + arch/arm64/kvm/arm.c | 4 ++++ arch/arm64/kvm/pmu-emul.c | 3 +++ 3 files changed, 8 insertions(+) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 7cd7d5c8c4bc..6336b4309114 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -46,6 +46,7 @@ #define KVM_REQ_VCPU_RESET KVM_ARCH_REQ(2) #define KVM_REQ_RECORD_STEAL KVM_ARCH_REQ(3) #define KVM_REQ_RELOAD_GICv4 KVM_ARCH_REQ(4) +#define KVM_REQ_RELOAD_PMU KVM_ARCH_REQ(5) #define KVM_DIRTY_LOG_MANUAL_CAPS (KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE | \ KVM_DIRTY_LOG_INITIALLY_SET) diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index e720148232a0..facf4d41d32a 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -689,6 +689,10 @@ static void check_vcpu_requests(struct kvm_vcpu *vcpu) vgic_v4_load(vcpu); preempt_enable(); } + + if (kvm_check_request(KVM_REQ_RELOAD_PMU, vcpu)) + kvm_pmu_handle_pmcr(vcpu, + __vcpu_sys_reg(vcpu, PMCR_EL0)); } } diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index fd167d4f4215..a0bbb7111f57 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -850,6 +850,9 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu) return -EINVAL; } + /* One-off reload of the PMU on first run */ + kvm_make_request(KVM_REQ_RELOAD_PMU, vcpu); + return 0; } -- 2.30.2