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 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 571D6C87FCB for ; Wed, 6 Aug 2025 20:39:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Reply-To:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:Cc:To: From:Subject:Message-ID:References:Mime-Version:In-Reply-To:Date: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=kcswufqwZeiVbOah5oR7VRWteUmksZlp7f05xG34s+k=; b=NezxlKfFdaKKG7gsmNzE8Sg6gl HusWLLgyAytC3Valcq1nvp+xPAL6/cJaTLatMOfaE6KRtkEQZ0MM7HkzCAeWAVuwfBMJGK597H4K5 rTYvRNi8lVimMwldgS2aRAlqoVysCjNyTUtyL8gYHG8CH3opue6Sb8nBAIvesAUmKtBSWFo/zp2jZ uiRbIeX1epzrDSfXkPhSo/H1FsLT02HP2x6B/f4IrIspUR6qzuki6bcP3pBP29Au0sN9GXd2IONzV hSaZb9XBeluggxTlnmIGMa3zvt4ZTJLW7GD2/frbQTWZhz1ME38+20Ln//gg83IJ2hDD1K5w3qZAX 6iEZPzGQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ujkvR-0000000GQlb-0ZTd; Wed, 06 Aug 2025 20:39:53 +0000 Received: from mail-pl1-x649.google.com ([2607:f8b0:4864:20::649]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ujkGr-0000000GGQs-1s2k for linux-arm-kernel@lists.infradead.org; Wed, 06 Aug 2025 19:57:58 +0000 Received: by mail-pl1-x649.google.com with SMTP id d9443c01a7336-23ff063d087so1424755ad.1 for ; Wed, 06 Aug 2025 12:57:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1754510276; x=1755115076; darn=lists.infradead.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=kcswufqwZeiVbOah5oR7VRWteUmksZlp7f05xG34s+k=; b=fkf07r+t95VqMQbIOIeYOp+1QSTQLdyVkG9KKQHdfwZWYxYjt/PjQj7VTZ0wrVDAWp 8I6ifPdPaNualeMEuXKnQSKcaiSCup/E7f3oE3mvvMw+CENc9MSDaohyBwlnHJrafoso fDP23jqfv50TMPyNzZ5zGOwmlVsMLe58Yw9WXxf2h12gaupecPBmuNWqNs8wT0FpDREc hPMq2zpUEI0L6hQClmCKuWh8UGkyUbOaHIYSPB60Z/sCDv+USaZh0aACZRrgjAnZCIf+ HSPfuunaZ5gYa3bWYUs3aH3sZglsqE8qFe4SNPkAkA/O8ksmqTwvSpMu/tWF8G1qLBjm 4CBQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1754510276; x=1755115076; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=kcswufqwZeiVbOah5oR7VRWteUmksZlp7f05xG34s+k=; b=fKh9EUGTFTs9X/g9JZtrk0iYBJovwoGVjYIw/LOlrNrJqaBMTpoYg7Gk09dvUYUPOF 7fQKH+rVsNHQhHS8FfMl7PU8SLc4I/bdRb2QrOEKavCFXm1qTXpWte0DsxAx1oBjSUgq ZcDxVs1KcPTxcqTehKQ+faD91vTV4kZyMMsfmr4xJUBbv/fx2TTIfQ93CkyYIG58Z8DD 7hmYFGBFLQQfVcYLlIY0CkToKxXIhG52z3UwnkopkqvnHnCFwisLBf29VDZEvfRud0He hX8yiADQ7ISNubxqD8dVKnAwRhCOk5bM5Nknbb949JzVwsYF5Sd07Vjqwgd9bbSh5T3Y RB5Q== X-Gm-Message-State: AOJu0YyCPYiSe4kqCGku7SutQq3JxHbbCHDMdO8SDM+kH/kr6iMF09ac zTRadSC8GR0JmjhYGVJgK9eQFTIso+IWO5Y+ywyo+1FTR1Bl8N2XY4dB6DAQPWJ9JE9U9dNNebk RiJ66gA== X-Google-Smtp-Source: AGHT+IE/UqkBVmIsYHo+3//+Db76eNFThoPapPb1lJatPNoq0GTt8I/qj7Zd+31YDzfBkj++w1pCOc8gls4= X-Received: from pjbnd14.prod.google.com ([2002:a17:90b:4cce:b0:31f:2a78:943]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:902:ec8e:b0:235:ef67:b5a0 with SMTP id d9443c01a7336-242a0b3e6f7mr55163055ad.36.1754510276193; Wed, 06 Aug 2025 12:57:56 -0700 (PDT) Date: Wed, 6 Aug 2025 12:56:37 -0700 In-Reply-To: <20250806195706.1650976-1-seanjc@google.com> Mime-Version: 1.0 References: <20250806195706.1650976-1-seanjc@google.com> X-Mailer: git-send-email 2.50.1.565.gc32cd1483b-goog Message-ID: <20250806195706.1650976-16-seanjc@google.com> Subject: [PATCH v5 15/44] KVM: SVM: Check pmu->version, not enable_pmu, when getting PMC MSRs From: Sean Christopherson To: Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Xin Li , "H. Peter Anvin" , Andy Lutomirski , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Sean Christopherson , Paolo Bonzini Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, loongarch@lists.linux.dev, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Kan Liang , Yongwei Ma , Mingwei Zhang , Xiong Zhang , Sandipan Das , Dapeng Mi Content-Type: text/plain; charset="UTF-8" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250806_125757_497865_CB65CC82 X-CRM114-Status: GOOD ( 14.85 ) 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: , Reply-To: Sean Christopherson Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Gate access to PMC MSRs based on pmu->version, not on kvm->arch.enable_pmu, to more accurately reflect KVM's behavior. This is a glorified nop, as pmu->version and pmu->nr_arch_gp_counters can only be non-zero if amd_pmu_refresh() is reached, kvm_pmu_refresh() invokes amd_pmu_refresh() if and only if kvm->arch.enable_pmu is true, and amd_pmu_refresh() forces pmu->version to be 1 or 2. I.e. the following holds true: !pmu->nr_arch_gp_counters || kvm->arch.enable_pmu == (pmu->version > 0) and so the only way for amd_pmu_get_pmc() to return a non-NULL value is if both kvm->arch.enable_pmu and pmu->version evaluate to true. No real functional change intended. Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c index 288f7f2a46f2..7b8577f3c57a 100644 --- a/arch/x86/kvm/svm/pmu.c +++ b/arch/x86/kvm/svm/pmu.c @@ -41,7 +41,7 @@ static inline struct kvm_pmc *get_gp_pmc_amd(struct kvm_pmu *pmu, u32 msr, struct kvm_vcpu *vcpu = pmu_to_vcpu(pmu); unsigned int idx; - if (!vcpu->kvm->arch.enable_pmu) + if (!pmu->version) return NULL; switch (msr) { -- 2.50.1.565.gc32cd1483b-goog