From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) (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 60E4633E376 for ; Fri, 31 Oct 2025 12:34:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.221.73 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761914073; cv=none; b=b7MBozIdAJyVd1wmLBUtu7u4e17oBiwm6PuU2sp7tosYxdc8DEYMVdeL3D2QwQIQrfZuWIGXXqsOnXilV1TGBm/msxBXj48SKuPSkTak+LZgL+DOTybFAS0EUh53sQiA/K+H91B1QG5kSuRnBN9jmuJeHjicIYwdiEjQFtP7wnM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761914073; c=relaxed/simple; bh=bTdeYhN0flt+JtdbGVAbBVozbl8U54zjEej7Slodurc=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=g0YL1EWtCARM1yDalUnQDSGstozGt7c0Nel/+5BVfpX25XKE1S6Lnp3YDir2VA3GPRfR2I3JXOAjitBlAbnRtOxM2nFly64odLni551HSbIBWbm2VGzoG/6oS4z/XiRvsbza/tdJwNkRpMUPfNh77p2H3RNJ9EEi5TuAYwFL414= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--jackmanb.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=yA5vOG4Y; arc=none smtp.client-ip=209.85.221.73 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--jackmanb.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="yA5vOG4Y" Received: by mail-wr1-f73.google.com with SMTP id ffacd0b85a97d-42855d6875fso1328829f8f.3 for ; Fri, 31 Oct 2025 05:34:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1761914070; x=1762518870; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=bTdeYhN0flt+JtdbGVAbBVozbl8U54zjEej7Slodurc=; b=yA5vOG4Y5zGtNCQ9vpFnjJoeIx9dxjHH62fKxXrd6ozSTh6WkYzt0V/s7ronZCNTMS /7MCNWWTJGnmynaecg73crwLxKi5wK96JaBC1AN6v6WTURbCXIk0nQxrE3NyrUTmMysM 4kGs4LLIKt4SH8SApZjFXvYALFQ2DOOunRk4Zd6ip6FRn6VfjgyecreJiIPSOszkgEYR g8uDC+AO9R9cppYsYp3jGJ/njX7U6wqXKA2quiFCT1G1gVgUC6H0CG2US5hyJ3lQMRB3 kBOu+xchWj+ap+qayC3Msh6ZVlHa7bGh2HcsevVKPkrPmInR5LK3uknE4gazlU3cagLj ydCQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1761914070; x=1762518870; h=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=bTdeYhN0flt+JtdbGVAbBVozbl8U54zjEej7Slodurc=; b=qoJPHN6hRYVm/ZNq45BUHEMjQ4Ln1xRtNQ7BnwfySvwkYA1bxTr0q7YusdYcQg3vUC uqH2D8lIG0Tl/+ELVLEhB1CVd5HfgDVl391Wz46iz2eCNlUShLzTJASQt21E5fEsgsnE MHyshF+68ZldEyiMa+RnCVHU0Ak29Sj4IoEcjxafjnSwju9sOfbYgfOPxjScAKmPkaAT fx9MWkM/FDW7dFJU5kBmf3o4ZEJWLwUqHMarQwU0elr9CUolhpl3cvZBksfdN3JLDVxy gvHmfQiWfudegjMZrZPXcmJ6v1ohBfXYESbBvV7ZzxAfDIEqPDmnBuTW7m6B64yyHheI XIuQ== X-Forwarded-Encrypted: i=1; AJvYcCWFdHkpEYZoI/L+0DXvpI/mIbVqeqTa4jKXpXqz8zv8qtPu+et1sOZI0Hdy6Cn8MxaenfgapNRqKrD6Pwo=@vger.kernel.org X-Gm-Message-State: AOJu0Yx57uIWNUq/5jS+cHdVF+5gg5c50EStdDaqjc7RjUCs7hYSMLES UCNpAKpqYUvavy5UBBwXvZYaOnf/xC6nOwQWj1uJbadsG/zULFx2bPDM4pyNM4b9flGCR9iLN9h nURarvimXfFSWfA== X-Google-Smtp-Source: AGHT+IEcmJDW+mdR12d71dV69TyMCqE2z9cLbKBFIHpu9vW9fhLESNvhwJbM2skNQbr67ZD5in1TdoBQvs6+DQ== X-Received: from wrbew12.prod.google.com ([2002:a05:6000:240c:b0:425:7c33:42eb]) (user=jackmanb job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6000:2f88:b0:426:d51c:4d71 with SMTP id ffacd0b85a97d-429bd675f4fmr2453446f8f.8.1761914069820; Fri, 31 Oct 2025 05:34:29 -0700 (PDT) Date: Fri, 31 Oct 2025 12:34:29 +0000 In-Reply-To: <20251031003040.3491385-6-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251031003040.3491385-1-seanjc@google.com> <20251031003040.3491385-6-seanjc@google.com> X-Mailer: aerc 0.21.0 Message-ID: Subject: Re: [PATCH v4 5/8] x86/bugs: KVM: Move VM_CLEAR_CPU_BUFFERS into SVM as SVM_CLEAR_CPU_BUFFERS From: Brendan Jackman To: Sean Christopherson , Paolo Bonzini , Thomas Gleixner , Borislav Petkov , Peter Zijlstra , Josh Poimboeuf Cc: , , Pawan Gupta , Brendan Jackman Content-Type: text/plain; charset="UTF-8" On Fri Oct 31, 2025 at 12:30 AM UTC, Sean Christopherson wrote: > Now that VMX encodes its own sequency for clearing CPU buffers, move > VM_CLEAR_CPU_BUFFERS into SVM to minimize the chances of KVM botching a > mitigation in the future, e.g. using VM_CLEAR_CPU_BUFFERS instead of > checking multiple mitigation flags. > > No functional change intended. > > Signed-off-by: Sean Christopherson Reviewed-by: Brendan Jackman