From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C6E91C05027 for ; Wed, 8 Feb 2023 18:31:46 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1pPpEG-00017C-16; Wed, 08 Feb 2023 13:31:36 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pPpEE-000173-MY for qemu-devel@nongnu.org; Wed, 08 Feb 2023 13:31:34 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1pPpEC-0002h0-3d for qemu-devel@nongnu.org; Wed, 08 Feb 2023 13:31:34 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1675881090; 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=UjIMNt6QbEWaBTMinb5F0Mjlorq11cP4pgDkqGZEChU=; b=b2HGf2K74EsmrYPN0jL2xSEf5cDryM10GJDmHZAtVV6Q5/C7eYMn5REvT9jSZZGBk/7ect tzox1KUH7dNb22Fs/suC0AYhDWXNSbfjo4IatlmO644Z/gfaqXMzrF531hR9KDj34VoEKw PSxvzZuJqtNCl6QBQf39j/iytgBlbi0= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-533-oSN_EdKnOdenzBNxrLCtZQ-1; Wed, 08 Feb 2023 13:31:27 -0500 X-MC-Unique: oSN_EdKnOdenzBNxrLCtZQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 6372C858F0E; Wed, 8 Feb 2023 18:31:26 +0000 (UTC) Received: from redhat.com (unknown [10.33.36.66]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E6B8BC15BA0; Wed, 8 Feb 2023 18:31:23 +0000 (UTC) Date: Wed, 8 Feb 2023 18:31:20 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: "Jason A. Donenfeld" Cc: "Michael S. Tsirkin" , qemu-devel@nongnu.org, x86@kernel.org, linux-kernel@vger.kernel.org, Dov Murik , Tom Lendacky , Gerd Hoffmann , Paolo Bonzini , Richard Henderson , "H . Peter Anvin" , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Nathan Chancellor , Borislav Petkov , Eric Biggers Subject: Re: [PATCH] x86: temporarily remove all attempts to provide setup_data Message-ID: References: <20230208180835.234638-1-Jason@zx2c4.com> <20230208131125-mutt-send-email-mst@kernel.org> <20230208131805-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.8 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, Feb 08, 2023 at 07:26:05PM +0100, Jason A. Donenfeld wrote: > On Wed, Feb 08, 2023 at 01:18:37PM -0500, Michael S. Tsirkin wrote: > > On Wed, Feb 08, 2023 at 03:14:38PM -0300, Jason A. Donenfeld wrote: > > > On Wed, Feb 8, 2023 at 3:13 PM Michael S. Tsirkin wrote: > > > > > > > > On Wed, Feb 08, 2023 at 03:08:35PM -0300, Jason A. Donenfeld wrote: > > > > > All attempts at providing setup_data have been made as an iteration on > > > > > whatever was there before, stretching back to the original > > > > > implementation used for DTBs that [mis]used the kernel image itself. > > > > > We've now had a dozen rounds of bugs and hacks, and the result is > > > > > turning into a pile of unmaintainable and increasingly brittle hacks. > > > > > > > > > > Let's just rip out all the madness and start over. We can re-architect > > > > > this based on having a separate standalone setup_data file, which is how > > > > > it should have been done in the first place. This is a larger project > > > > > with a few things to coordinate, but we can't really begin thinking > > > > > about that while trying to play whack-a-mole with the current buggy > > > > > implementation. > > > > > > > > > > So this commit removes the setup_data setting from x86_load_linux(), > > > > > while leaving intact the infrastructure we'll need in the future to try > > > > > again. > > > > > > > > > > Cc: Michael S. Tsirkin > > > > > Cc: Dov Murik > > > > > Cc: Tom Lendacky > > > > > Cc: Gerd Hoffmann > > > > > Cc: Daniel P. Berrangé > > > > > Cc: Paolo Bonzini > > > > > Cc: Richard Henderson > > > > > Cc: H. Peter Anvin > > > > > Cc: Philippe Mathieu-Daudé > > > > > Cc: Nathan Chancellor > > > > > Cc: Borislav Petkov > > > > > Cc: Eric Biggers > > > > > Signed-off-by: Jason A. Donenfeld > > > > > > > > I think I'll be happier if this is just a revert of > > > > the relevant commits in reverse order to make life easier > > > > for backporters. > > > > Unless that's too much work as we made other changes around > > > > this code? > > > > > > I think that's going to be messy. And it won't handle the dtb stuff > > > either straightforwardly. > > > > List of Fixes tags so people can at least figure out whether they > > have a version that needs this fix then? > > 7.2 is when the functionality started causing problems for most people. > But the buggy code goes back to 3cbeb524 in 2016. We can't rip out the full setup_data support back to that point. That is deleting significant features that would break -dtb IIUC. For that we would need to have a deprecation period to announce the incompatibility. I was thinking this would only revert the RNG seed pieces which have negligible user impact. 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 :|