From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (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 7A2922FFDD5 for ; Wed, 17 Jun 2026 13:37:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781703475; cv=none; b=PzgccBhojmOZOAECdia+J3UwnvmO0f4vQwfl09exP2C1/jho7J5XZO3KRQx8tKpyrbFY2v1Nc1+1G6AjfXhkyLRJFxMPExbkLWgXCJohpowTlRWmj66HSyLqihHzEwkXgzLt+vtgKo0c9doo6RGee/b9P0T6/hmkumJ99LNJ+Ek= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781703475; c=relaxed/simple; bh=7jvheL/qAmaTTHS5xK+l/tVp5Gsh72Hu0Hh7hsIjBG4=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=XgvLY1oYTvAUqRHMsoYCtO+JZaUEFQnIBElHTzvjKcXuL+73PgsjUsU6rEWgkwMOVPK01JSXmkkllt20ArQK9UAl7oZbxaR+YXIoYNBsPIq6uOQ14aJoEawjono+Y5K9OJcLGdDB9/iidzn2ZCk3trS8VCcuWKecAp2m9/npEPw= 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=sFcohk0Z; arc=none smtp.client-ip=209.85.215.202 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="sFcohk0Z" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-c88ab059052so109029a12.1 for ; Wed, 17 Jun 2026 06:37:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20251104; t=1781703474; x=1782308274; 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=xafrOaxeWuRZe0/2sgztMbGOHrwrXJkZEqKtZ2nD9W4=; b=sFcohk0ZrduDlVIsm9G+jH0YdQw8tBGqi6XPwQCxZbGKKqNU23G8fw+0gpIBqZ421b L04cSKYk7LfLuJvEgm5kkxDBOXaXYmOyxUrcGXkoAwoR4QAaugt1CMwmLfSU66l86Wxc SiaPR5FkAThQmRiGIMDf74hszKXTd398SFZqhBs8MSDlLWQveckzf97zIWNCSEXGPpPZ nN4aD66wAUDNm3tBaDpv6vGIxUpLYXyZbOQrL8s5CF+FjSMZdGnZrer63CayXU6D5hMM XOUvF5MXu3yLXnCmv/XFWaTCplDkANFoUX9eQnYwhnl92hDqxQq1fcTEMmyIsfG8F+FF seWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781703474; x=1782308274; 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=xafrOaxeWuRZe0/2sgztMbGOHrwrXJkZEqKtZ2nD9W4=; b=pN5WC1MDju92JKP/l65shnJARORqwtuczfWhyN7YrKyj74LZf2WtdtWjL7+3DX79OG ZqLE4tkzxu4tG8roFReFEZKJDtDK1S3ZYiTnaMeah+1m5QKj/laEFJjg34pyb1731jFh sU52KMf6CgJdmvON6U0eFDiqXPqiZrdPjCZ8RlLSNFtaYNjpUBN4IiPPeboufjI8mquO +9/FNh17FDaOIIJS7iR1q+JnqnR4aKKCCM2rH9NMgQLs9Zs79PQNNbJrM+7iRp9GzdSx ZDopdFgIaSo99Xje0nh8m8CSNsKbfV+eFK+AVWJgNA1DaJNMW9cR7MftUfoE2rnHz+Jw QllA== X-Forwarded-Encrypted: i=1; AFNElJ9YjOs5ff+868xSNswyEer8r1sBjudac7HHB5pE9NCXsYQfBRDXNuUpw10b5E6XkQrPYPx9KHZ9yzo0MOA=@vger.kernel.org X-Gm-Message-State: AOJu0YwFH7JEsZHaVs3hbgKYXei/eBHUYPxYEX5EKjRVOkvum9ZTiHhn I0B1JrksNEs1bYiJhpoc/sc1xGlNA0BGpGibKwlN5RmbLKujTNwLbmPshP7ZYWca4Fhyz2HWtlc O4cmU7Q== X-Received: from pgbcr2.prod.google.com ([2002:a05:6a02:4102:b0:c86:93b:4965]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:4307:b0:3b4:731e:6fad with SMTP id adf61e73a8af0-3b8db0d66bbmr3049921637.16.1781703473551; Wed, 17 Jun 2026 06:37:53 -0700 (PDT) Date: Wed, 17 Jun 2026 06:37:52 -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: <20260611123528.572255-1-joro@8bytes.org> <20260611123528.572255-5-joro@8bytes.org> Message-ID: Subject: Re: [PATCH 4/4] kvm: svm: Support KVM_SEV_SNP_PAGE_TYPE_VMSA at SNP_LAUNCH_UPDATE From: Sean Christopherson To: "=?utf-8?B?SsO2cmcgUsO2ZGVs?=" Cc: Paolo Bonzini , x86@kernel.org, Tom Lendacky , Michael Roth , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, coconut-svsm@lists.linux.dev, Joerg Roedel , Jethro Beekman Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wed, Jun 17, 2026, J=C3=B6rg R=C3=B6del wrote: > On Wed, Jun 17, 2026 at 06:00:39AM -0700, Sean Christopherson wrote: > > On Wed, Jun 17, 2026, J=C3=B6rg R=C3=B6del wrote: > > > (which has happened a couple of times already). > >=20 > > Examples? The SEV features thing jumps to mind, but I don't recall any= others > > off the top of my head. >=20 > I was referring to KVM-induced changes to SEV features, but thought this > happened more than once? Ok, so it took us a few times to learn our lesson. I still don't see that = as a strong argument for new uAPI, especially not for VMSA pages. I am very fir= mly of the opinion that letting anything but the host kernel configure the VMSA= is beyond stupid, but unfortunately we're stuck with AP_CREATION. Expanding t= hat surface has a very, very, VERY high bar to get over.