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 D9AB7C433EF for ; Tue, 18 Jan 2022 15:18:21 +0000 (UTC) Received: from localhost ([::1]:44126 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1n9qFY-0006ZW-SW for qemu-devel@archiver.kernel.org; Tue, 18 Jan 2022 10:18:20 -0500 Received: from eggs.gnu.org ([209.51.188.92]:40930) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n9oTt-0003ll-Gg for qemu-devel@nongnu.org; Tue, 18 Jan 2022 08:25:02 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:32898) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1n9oTq-0003QY-BC for qemu-devel@nongnu.org; Tue, 18 Jan 2022 08:25:00 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1642512297; 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:in-reply-to:in-reply-to: references:references; bh=dVQmUazxr0xjSVJUl2JL5q5VPHJCuvU5YrVgh98JUQc=; b=ZZmL08BS/byz3G06oEzBLD8GXizkOyR1yLKBm4qiJuAMYsYhK82w4vKNfW5DovsWTZyFLR fn1sBPqTm+ChiHpC1CQh9wXCvstClBbsuc0kifIqXrrang90JhbM1EkLBbhZfIGUlRr2Kw WRSaGO2Awj9fMaDkxilTfODUDTCnWH0= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-120-S20nI0rMOjy666nLOfbLUg-1; Tue, 18 Jan 2022 08:24:48 -0500 X-MC-Unique: S20nI0rMOjy666nLOfbLUg-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B7083801B0B; Tue, 18 Jan 2022 13:24:47 +0000 (UTC) Received: from redhat.com (unknown [10.39.195.32]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 0FFE26A023; Tue, 18 Jan 2022 13:24:43 +0000 (UTC) Date: Tue, 18 Jan 2022 13:24:40 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Paolo Bonzini Subject: Re: /usr/shared/qemu binaries Message-ID: References: <1E2E0E52-B384-404C-BD72-5697A611EEC5@livius.net> <7403b918-d2c7-1d3f-8ef8-786db90fcbea@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.1.3 (2021-09-10) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.7, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=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?= Cc: Peter Maydell , QEMU Developers , Alistair Francis , Liviu Ionescu Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Jan 18, 2022 at 01:30:35PM +0100, Paolo Bonzini wrote: > On 1/13/22 18:23, Peter Maydell wrote: > > On Thu, 13 Jan 2022 at 17:13, Paolo Bonzini wrote: > > > > > > On 1/12/22 14:56, Peter Maydell wrote: > > > > Those are UEFI firmware images which are suitable for using with > > > > the arm/aarch64 "virt" board. They're only used if the user specifically > > > > asks to use them on the command line (eg with > > > > "-drive if=pflash,format=raw,file=pc-bios/edk2-aarch64-code.fd" or > > > > similar). > > > > > > There must be lots of zeros in there. Maybe we should tell QEMU to > > > unpack firmware .gz or .lzo files? > > > > Not hugely keen on adding more "do what I mean" behaviour... > > Certainly no autodetection (with writable pflash there's the possibility of > the guest causing real problems), but we already distribute firmware as > compressed files so the zeroes _are_ causing problems for us as well. We > are just telling the users to deal with it. I don't think compression will make a meaningful difference here. The firmware is split with both code and vars files. When booting a guest the vars file is deep copied. The vars file can't be compressed because it needs to be writable at runtime. So for 100 guests, you have 1 x 64 MB of code.fd plus 100 x 64 MB of vars.fd. If only the code.fd can be compressed, that isn't going to dent the disk space consumed. If we want the firmware to be smaller the file could be made sparse on disk. If the firmware only needs to be used with pflash, then we could distribute it in qcow2 format instead of raw, which would get rid of the zeros too. 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 :|