From nobody Tue Dec 16 14:39:07 2025 Received: from mail-pf1-f201.google.com (mail-pf1-f201.google.com [209.85.210.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0AD6D30C626 for ; Sat, 6 Dec 2025 00:18:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764980336; cv=none; b=apOTTqiUrcgXIoDnrwQjJXaK1/aBD8Y67yDhkqub/7dxXqo2+1ER3kc2QtWEita7YBwGIcnWHzBjq24ivQ/XIR0ZcCXgdwkuvzJB76y96Td7E6JLoYgu9zVCLPJ0jjNaxSQ2N0H2y8mxlW6wEoL2xEKUzwzDEreCmu5dNcSlhJE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764980336; c=relaxed/simple; bh=EbuHjkM11wJSgkGWY2aSFlMpNr7gwy2PyHzdmFLt294=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=cilu/f3Kpz3cZhu3V1ZK0mLptnba6yliO3nAyfaU9roa0sanfDtWZbAYbepnDx2HMMpwLUtr0vD92+6m7i9rUpmpAXhGyZKlFhVOArfn/winlUSF2A5fKMLUjJR+ygIkvBc40pd03X5dNW9ZtV+tohZezXL+3j95ASVbs2QoIYQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=iKSVd+rd; arc=none smtp.client-ip=209.85.210.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="iKSVd+rd" Received: by mail-pf1-f201.google.com with SMTP id d2e1a72fcca58-7b8ed43cd00so3149230b3a.2 for ; Fri, 05 Dec 2025 16:18:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1764980333; x=1765585133; darn=vger.kernel.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=n8V9DDSigR69uE32CWTID9idTpYitJ2rw2w6q4YtJdw=; b=iKSVd+rd86Opv0mE38U0ubpL+DeS273fzlevHCCHWm4bq8qBj4Z7SYdKpUkzVJO/dh 2G3Lmxw2qQW/SSW4FAdmJnOxm8Bb5X0YM1bJJQ8KmSKdvfCHYLlZ6GkZeYUPPHEHGQfh p3qKRmww80TkTY81zwp2rGZI1VJ74TweTrE+ID+RvPmOk++z9YKJYKGhjuejfEIHcJCp BTGR6TXuPxC4QDdACkE5tvaH+SMyW+iSan1OzQCjafUpvGtzqWv18woR6bZRm1VWkS3e mAtlZ9J+6oOD1wBYA51YJ9VqPTbcAgC5pJh2Z+NYfnO/ZsFRTXMlwTsgsTWkcZthrZAM YfyA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764980333; x=1765585133; 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=n8V9DDSigR69uE32CWTID9idTpYitJ2rw2w6q4YtJdw=; b=aERBiR+xZr4WvNZwE31DHilWON9pfm0RGjVp347V3EWEnEVl9k++Ourv0BSNkx/7Vi 8U32PzJqwlU/zY6P42LHZ3KdLolY2ThVK1WJ+MzpsiDlMOKIhPnKfdTV8WuuCBdPzkPk a5dDp9fM3wO0kpyH7zqNAbTLHTCf1LDjehSa82n3K5XJLlRcq4NpiUnIC6HIp4rdaqly G2qjV3KU05JtIFxPegr65uwVy7yjMfPytCkX2LVdBMQkz//xTPw2tkanwCb1LIbvy9gl caf7ae+8vGnGxGeh9PfvjbLlr2pUT+KxnxMN0xWdaxfCuKyUX2OWYJd4VSjWCkIAvU+j 1Z1w== X-Forwarded-Encrypted: i=1; AJvYcCV0ggTo59FFbht3vQikfNNgWX+wtzW4FibzJNSu9DCPLGqa0SkEpopoOpbt2dKb3MvjskOp7/JkCoqtQJ0=@vger.kernel.org X-Gm-Message-State: AOJu0YzR9EWQ+VR4y0tYZKidzVhanMASs1XXXf7gArOvpOFJDNQVOI2A wUog4g/f4Xt+/6W4JJ0143jhcur/YWqTHcEILVVcyH6DZt+eKm+m5B/rBziQmRO2sX62Omd8vo1 bG6txNw== X-Google-Smtp-Source: AGHT+IFvgfK2a2snqIy1Rm8aE6qptyZkQEpan42/+C7VOcIZpnFc5T7dKOJ6QhHIoZwkwV6ZMBDtCsCouY0= X-Received: from pfbim5.prod.google.com ([2002:a05:6a00:8d85:b0:7b0:e3d3:f042]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:aa7:888d:0:b0:7e1:89ad:991 with SMTP id d2e1a72fcca58-7e8c6da8d28mr855283b3a.32.1764980332931; Fri, 05 Dec 2025 16:18:52 -0800 (PST) Reply-To: Sean Christopherson Date: Fri, 5 Dec 2025 16:17:19 -0800 In-Reply-To: <20251206001720.468579-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251206001720.468579-1-seanjc@google.com> X-Mailer: git-send-email 2.52.0.223.gf5cc29aaa4-goog Message-ID: <20251206001720.468579-44-seanjc@google.com> Subject: [PATCH v6 43/44] KVM: VMX: Initialize vmcs01.VM_EXIT_MSR_STORE_ADDR with list address 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, Mingwei Zhang , Xudong Hao , Sandipan Das , Dapeng Mi , Xiong Zhang , Manali Shukla , Jim Mattson Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Initialize vmcs01.VM_EXIT_MSR_STORE_ADDR to point at the vCPU's msr_autostore list in anticipation of utilizing the auto-store functionality, and to harden KVM against stray reads to pfn 0 (or, in theory, a random pfn if the underlying CPU uses a complex scheme for encoding VMCS data). The MSR auto lists are supposed to be ignored if the associated COUNT VMCS field is '0', but leaving the ADDR field zero-initialized in memory is an unnecessary risk (albeit a minuscule risk) given that the cost is a single VMWRITE during vCPU creation. Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/vmx.c | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 3f64d4b1b19c..6a17cb90eaf4 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -4933,6 +4933,7 @@ static void init_vmcs(struct vcpu_vmx *vmx) vmcs_write64(VM_FUNCTION_CONTROL, 0); =20 vmcs_write32(VM_EXIT_MSR_STORE_COUNT, 0); + vmcs_write64(VM_EXIT_MSR_STORE_ADDR, __pa(vmx->msr_autostore.val)); vmcs_write32(VM_EXIT_MSR_LOAD_COUNT, 0); vmcs_write64(VM_EXIT_MSR_LOAD_ADDR, __pa(vmx->msr_autoload.host.val)); vmcs_write32(VM_ENTRY_MSR_LOAD_COUNT, 0); --=20 2.52.0.223.gf5cc29aaa4-goog