From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pj1-f74.google.com (mail-pj1-f74.google.com [209.85.216.74]) (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 6511715E5BB for ; Mon, 13 Oct 2025 23:30:44 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.216.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760398245; cv=none; b=XoiR1c3GEvQLNUx0RiMFcN/s8m0o+bVUKSpWuqIplIn6bg+JvofW7+qwsKIIKXjy0WrvMeMCKKHBM9ail8MhI1CEH3oIQYslmJH2SdbTYyZ9qAdcQzyT27RIdNR8xc4UsK5b4vnI/ZttLxM3Z3DITLGmIWv5jh8FYUFcfsqgYAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760398245; c=relaxed/simple; bh=f1t956JBV+YwJMh+YwrrZfOciYvg7blVAnIMvPKNYWY=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=C6k8655Vs6VHNTsdzSwYQRAggJmD1z8D/WpVTLaLRAFF2g6oreNsUkUTZtTBQvopYaeqzmwlG9e3JocX1BwdNgUFJScHN8VJM0yfogDvEBAzkcyY7tDJjVT4b7DjbgW6Cqm/5u3RFKqNoL9DzNFi7fhs+Xq22mVrukRQJ5xxZS4= 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=Uph6FHzP; arc=none smtp.client-ip=209.85.216.74 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="Uph6FHzP" Received: by mail-pj1-f74.google.com with SMTP id 98e67ed59e1d1-330a4d5c4efso8550676a91.0 for ; Mon, 13 Oct 2025 16:30:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1760398243; x=1761003043; darn=vger.kernel.org; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:from:to:cc:subject:date:message-id :reply-to; bh=08aB01K3QlDxNQ6Di+ZC0Fy9ecw0hHQXKJJoqFOXoow=; b=Uph6FHzPc/b+vglLfbjZCr6KjDJ2zmgxbDJayKIw5OqT1WmL19SVwuCjuYq0HNn6BK eGHUGRKOGrc3kO420C0+fBZn5s0tZD4i7FFSatS0ltUBQL49XOYorDGQ72acddkim8ip ce9ryTKim646cxrT9G6WKmhhg27Yw80v5+MmCwvJn4UmTls+T0oR3x6lFHcYt4UsQ1ov p4iQwEKTzteS69d7HrWbRdLOrUv9b+zBiIulj7OwgZOSLu641FsfS+Jf6jNc0W5iMrFh uKY14V5JLNw3eXSYTg1dbdm9NXVP7/645gmStX4/0wQJeOgXZnO2gOO0GUvOfApmHlu1 J2WA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760398243; x=1761003043; h=content-transfer-encoding:cc:to:from:subject:message-id:references :mime-version:in-reply-to:date:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=08aB01K3QlDxNQ6Di+ZC0Fy9ecw0hHQXKJJoqFOXoow=; b=BmmztHTLgMqs3rudn+fbHb/qymb5GANa0Tk8MtiY0LDCnYumc/7WHx8KXPcPZZeinq 4mOYLEQXWWZp/m3PADcfOdloLy6FSO17HCkHBdO37IAuRMRUOaUaakkxZWz/Vk9uWUo1 KqiaJoa1XKwFZy9tfqK8h2AuqKl6qY52Qh+At1WwDEwy2A6V6MzYDaV3VDH2eASmd+Qq BlpavG/nW5wJOe+riKaxTIuTlvFQ+iikRPSPfiIOdbCZgJdczooPpC2tASB4c09mhSdE ZVLiijQnEkG4whe+yHEMxXwhhdlrM4IKV9C6PFuDGCVSUXBRTaa+QQ98u2o09fu5QcXH fbUQ== X-Forwarded-Encrypted: i=1; AJvYcCVEsQbfcA2259XLhw1uzCJplQj2hJj/jlfLFQbg6zOeONmOuzv4mgpvcN4lU/In2y3GLW+DrKUkoLzCFcA=@vger.kernel.org X-Gm-Message-State: AOJu0Ywcx9sbShX/Rcf273dO1FYQk1w1V2QVyo6n77mTR1eim+K1WjXL D1mtuxcVd2WVpYvcJEhDzuX6rI6Fsak1Nqn4xLCU4qbysjXWmUf+Fu+wycOj6k+Xul31IcwR7np xvOv39A== X-Google-Smtp-Source: AGHT+IHs68Jiesyq8CVwopkosF1NFYrZ8tVJ5yK1fRCuny9H+M0GlqQ+GEI/HXfswBxaNk8YEghSh7Wv9pM= X-Received: from pjbgl20.prod.google.com ([2002:a17:90b:1214:b0:330:acc9:302c]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a17:90b:1a87:b0:339:f09b:d36f with SMTP id 98e67ed59e1d1-33b513a1e0fmr28253894a91.28.1760398243550; Mon, 13 Oct 2025 16:30:43 -0700 (PDT) Date: Mon, 13 Oct 2025 16:30:42 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20250922162935.621409-1-jmattson@google.com> Message-ID: Subject: Re: [PATCH 0/2] KVM: SVM: Aggressively clear vmcb02 clean bits From: Sean Christopherson To: Jim Mattson Cc: Paolo Bonzini , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , kvm@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Mon, Oct 13, 2025, Jim Mattson wrote: > On Mon, Oct 13, 2025 at 2:54=E2=80=AFPM Sean Christopherson wrote: > > > > On Mon, Sep 22, 2025, Jim Mattson wrote: > > > It is unlikely that L1 will toggle the MSR intercept bit in vmcb02, > > > or that L1 will change its own IA32_PAT MSR. However, if it does, > > > the affected fields in vmcb02 should not be marked clean. > > > > > > An alternative approach would be to implement a set of mutators for > > > vmcb02 fields, and to clear the associated clean bit whenever a field > > > is modified. > > > > Any reason not to tag these for stable@? I can't think of any meaningf= ul > > downsides, so erring on the side of caution seems prudent. >=20 > SGTM. Do you want a new version? Good gravy, no. :-)