From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f202.google.com (mail-pl1-f202.google.com [209.85.214.202]) (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 D177F427A1D for ; Thu, 5 Feb 2026 15:53:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770306790; cv=none; b=URoU+q07iM/nq6ajx4bNPQn+Dgpwz4RFXENIIHPUkR9cIPHKB6SaGWhqFzOD0OwIyF6iKHCA1YIdp1CToWV1kBGPm8PC3+v5Gi2LqjkZqJu7lj8lem20bL5WgbOllBWoE0u2jpRFOU6mNgtsLtpmAHghacafVYlOIdrqGkRft1A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770306790; c=relaxed/simple; bh=YqRD+cKBfYWmS+ctu1ucUed79XYvh05hyJ19wxjDW/s=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=mhShub7VhLrKm6KMlYJDfPUZKgQTN7lkzmGu5JnZ2p2hrxcC5AKVfXL3gHMrR+CM5gFNb4qm1zZ06OvfuNshvuTW+4woLaQeEbZXxf52d/crw2I8+MYRVYeBM09fzNZSK47CeaymAZRGk/CQDuk8cVEe44VrRdM/M4MQlS7JYIo= 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=oLTZX95K; arc=none smtp.client-ip=209.85.214.202 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="oLTZX95K" Received: by mail-pl1-f202.google.com with SMTP id d9443c01a7336-2a943e214daso23723975ad.3 for ; Thu, 05 Feb 2026 07:53:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1770306790; x=1770911590; darn=lists.linux.dev; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=Xcx7wlzL60d1Aa7ekaPBgmgQ/lwDEM/p/AnSieBZ0xQ=; b=oLTZX95KzC2aoxNQe5Q5m9mFEIAD2+UXNz4YkPJ7XBhfC3t/A6y+/N/vXoDO1oxXyy y7Z/9a4Y/Ygze26Kseh38+ez6i2lB1rRSvWSZdk622feO64wky9pgrCYTRpbOSz3a3Bk WdbF88xoJxBQpxvY37uMr/8+uvgweUGoSQ3ugArK1RxIOCwVvT38Bc7cKksMFKbKJYKV NCSiJB8wYF3YqGmMLakkngEeTvqFxKsW5AAQgXQ4nwj2GhzSbj8AWYdolIxW40scUiId ILkPG1Q7rAhJl/9i/OOATx1hj4IXXulrGx9mamrEoomHnoF568IWLN6kbhVVw4sK+TcE XmpQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1770306790; x=1770911590; 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=Xcx7wlzL60d1Aa7ekaPBgmgQ/lwDEM/p/AnSieBZ0xQ=; b=h52ar4i5CpNFsX1kou1X2/IgWUXpTP9mr7yKHwT4V8en2eMVJLVCsyM6D9f0BUfUWf NOsyka2HM+/KMw8YFFBbglBsY0PKvBqVpf5tdJFSL3X2GIXzQ5BD3HH3cK07M5dYAA5j ElhaMWmAkDG7GPDJu7KfxhYCtzdT7GiuJ0KGcxO5Hj/aPUM/ZhrhWS5nEewSAv3VrtmM 31CiCjE46IFYZVoVND8+srns2VXYozXSIviao/5uj4G1L1ZtHgTBlT36bO8cWgiV4Jkv hmcmR6w+iYkZQ6gDHPje4awEi3xmceGJQbON4iphkJzuSjdLvsJ8141tOLa8oc/+x55W FAzA== X-Forwarded-Encrypted: i=1; AJvYcCU/nnwDyEblnDRmYTb3wjaHY6CY4FCqJjHTJ27yx6o6u2JCWqWuCaWX7Euvnl+yyFDX24+zzpRHwMa2@lists.linux.dev X-Gm-Message-State: AOJu0YwXMA9F2NuW+IziRbDf0I3Qn6VkhJ327p4ra2OrQxPYz3oHdM8V 3PP7n2WtslZ5M5MJXzE9FXuIvq06wwqJDJwCQz4M1LtXcREmMkyZfUqvdH0i7A7PQ8T4P46FL6k IzgT0Tg== X-Received: from pgi124.prod.google.com ([2002:a63:882:0:b0:bc0:d9a9:8a8e]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:7fa8:b0:358:dc7d:a2cc with SMTP id adf61e73a8af0-393720d9943mr8123776637.17.1770306790120; Thu, 05 Feb 2026 07:53:10 -0800 (PST) Date: Thu, 5 Feb 2026 07:53:08 -0800 In-Reply-To: Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260129011517.3545883-1-seanjc@google.com> Message-ID: Subject: Re: [RFC PATCH v5 00/45] TDX: Dynamic PAMT + S-EPT Hugepage From: Sean Christopherson To: Dave Hansen Cc: Konrad Rzeszutek Wilk , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Kiryl Shutsemau , Paolo Bonzini , linux-kernel@vger.kernel.org, linux-coco@lists.linux.dev, kvm@vger.kernel.org, Kai Huang , Rick Edgecombe , Yan Zhao , Vishal Annapurve , Ackerley Tng , Sagi Shahar , Binbin Wu , Xiaoyao Li , Isaku Yamahata Content-Type: text/plain; charset="us-ascii" On Wed, Feb 04, 2026, Dave Hansen wrote: > On 2/4/26 06:38, Sean Christopherson wrote: > ... > > We can and do have tests and VMM support, but it's all out-of-tree (for now). > > All I'm saying here is that I'm ok landing the S-EPT hugepage code in advance of > > guest_memfd hugepage support, e.g. so that we don't end up in a stalemate due to > > cyclical dependecies, or one big megaseries. > > Does "landing" mean having it sit in some topic branch, or pushing to Linus? I was thinking pushing to Linus' tree, but a topic branch could likely provide almost as much value? > I'm all for getting these hellish dependency chains out of the way, but > we usually try pretty hard to avoid having dead/unreachable code in > mainline. > > If it is something you want to do in mainline, we should probably do a > bit of cross-x86/kvm brainstorming to make sure there's no other option. I'm a-ok starting with a topic branch. If maintaining that branch becomes too costly, then we can always revisit things. And that would probably be good motiviation to beat guest_memfd hugepage into shape :-)