From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4D51A823D4 for ; Tue, 23 Jan 2024 19:57:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706039861; cv=none; b=ZAgzLwWeMJiTSsxr4YQf/xJ19AnSOBQEiU7dM30mHM46RWVW6LCV5Id3L4quyhTp5diltx8s5xdJ7T7xG4Q1zl3WMkoCTj1gsWg8m0NLYWxHeG2FehlcQgPEaOJRwMpUF2pwSaeEfmVz+55yEUW+Iu1V1xH6exOPHXLh6w4uxhA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1706039861; c=relaxed/simple; bh=gv1DX3qDboW/6yRx2XyJUGmrHzFoE9rDCyOWbJVc7vM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: In-Reply-To:Content-Type:Content-Disposition; b=RZ6IjhuudSZrT1NtW2Tlpu1jGd2/i9GV7aZr3t0MErj6V3Ca5xdzpg/P2b3P2LHjZfZ8Cc9yWJ9LB6Grq4yhGBiNiEYJfdl897D5ajWgMIbporgrZRVXbStczQkSli5zmo35DJtsFQathoHgKayqQV8GC33ufOkzu1NQ6hPNKII= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=Ts02z8Hn; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Ts02z8Hn" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1706039858; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=4FmzS2EE1as4Ca/VNKz3nSgRcmIcg5qQtytba5yF0mQ=; b=Ts02z8HnuLj6BR1JIyzlJ+NUeU7AehcBLHyoykIoUf6zFhyIMeRqnmN0FoHp1SZL4c8wlu 5/JPv8aHCkOUatpDa/zRbL/809zrPKFJGPVgOSyRaebHGijdJgmv2f/W6+Es7ue8yO6xs6 C9B52qqa6kFOOH/IN8P6TKLkIGg+qew= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-588-9be9ZkYIOdeDYgUgTaHQbg-1; Tue, 23 Jan 2024 14:57:34 -0500 X-MC-Unique: 9be9ZkYIOdeDYgUgTaHQbg-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C4FE3185A784; Tue, 23 Jan 2024 19:57:33 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.3]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D91562166B32; Tue, 23 Jan 2024 19:57:31 +0000 (UTC) Date: Tue, 23 Jan 2024 19:57:28 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Dan Williams Cc: Nikolay Borisov , Kuppuswamy Sathyanarayanan , linux-coco@lists.linux.dev, dave.hansen@linux.intel.com, x86@kernel.org, kirill.shutemov@linux.intel.com Subject: Re: [RFC PATCH] virt: tdx-guest: Remove quote generation via ioctl Message-ID: Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= References: <20240123160704.1270147-1-nik.borisov@suse.com> <65b00e191087c_37ad29436@dwillia2-xfh.jf.intel.com.notmuch> Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In-Reply-To: <65b00e191087c_37ad29436@dwillia2-xfh.jf.intel.com.notmuch> User-Agent: Mutt/2.2.10 (2023-03-25) X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.6 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit On Tue, Jan 23, 2024 at 11:06:01AM -0800, Dan Williams wrote: > Nikolay Borisov wrote: > > > > > > On 23.01.24 г. 19:51 ч., Kuppuswamy Sathyanarayanan wrote: > > > > > > On 1/23/24 8:07 AM, Nikolay Borisov wrote: > > >> When this driver got merged initially there was no widely agreed upon > > >> interface how the quote generation interface will work so having an > > >> ioctl made sense. However, there's now a vendor-neutral interface via > > >> configfs. Just remove the old ioctl interface and leave only the the > > >> configfs one. > > >> > > >> Signed-off-by: Nikolay Borisov > > >> --- > > > > > > This ABI allows the user to get the raw report which is further used > > > for Quote generation via vsock. AFAIK, some vendors (TDX users) and > > > DCAP user libraries are still using this ABI to support attestation over > > > vsock model. > > > > > > Don't you think we should wait till there are no users before considering > > > removing it? > > > > Given that hw with TDX was just released I'd be surprised if there are > > any users? But then again, this is an RFC so let's get opinions :) > > > > The assumption is that this tdx_guest_ioctl() ABI has never appeared in > an enterprise distro kernel. If that assumption is valid, it > significantly reduces the long term support exposure. This ioctl is present in current RHEL-9 kernels https://gitlab.com/redhat/centos-stream/src/kernel/centos-stream-9/-/blob/main/drivers/virt/coco/tdx-guest/tdx-guest.c?ref_type=heads#L69 and this is exposed to users when running RHEL-9 guest on Azure cloud with TDX support. I've not directly checked, but I would assume it is also probably included in Ubuntu LTS kernels too, since they also target TDX in Azure. No idea what the status of SLES is wrt TDX / Azure offhand. With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|