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 1BBD0CDB474 for ; Tue, 17 Oct 2023 05:47:31 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qscun-000111-0Z; Tue, 17 Oct 2023 01:46:49 -0400 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 1qscul-00010e-CQ for qemu-devel@nongnu.org; Tue, 17 Oct 2023 01:46:47 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qscuj-00069J-9U for qemu-devel@nongnu.org; Tue, 17 Oct 2023 01:46:47 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1697521603; h=from:from: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=EUSMWN5wzpWjp87Hswug2p1wT9W7iuOz11i3m35A7cc=; b=UiYbb5JiObiVJ4LSJmeNLxZushsrYHO/0JzB1KUELrexDgPtZwqdOBVIAoLi71yflNh76Q rNJeLZ/ohbc2xOn/poxmwJvDvP0kZZaLD8ezCaSbjg8jfMg6n5BEPoYfw/iOiBF7QldEDR gdulhN8lADImXAIOhslo+alAn1MaVuU= 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-172-Ibtc4We9Oo2t2lh1yYdokQ-1; Tue, 17 Oct 2023 01:46:29 -0400 X-MC-Unique: Ibtc4We9Oo2t2lh1yYdokQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 63F73858F1C; Tue, 17 Oct 2023 05:46:29 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.39.193.56]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 431801C060AE; Tue, 17 Oct 2023 05:46:29 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 4271B21E6A1F; Tue, 17 Oct 2023 07:46:28 +0200 (CEST) From: Markus Armbruster To: Paolo Bonzini Cc: qemu-devel@nongnu.org, Michael Tokarev Subject: Re: [PATCH 03/17] meson, cutils: allow non-relocatable installs References: <20231016063127.161204-1-pbonzini@redhat.com> <20231016063127.161204-4-pbonzini@redhat.com> <87edhuixx5.fsf@pond.sub.org> Date: Tue, 17 Oct 2023 07:46:28 +0200 In-Reply-To: (Paolo Bonzini's message of "Mon, 16 Oct 2023 23:29:56 +0200") Message-ID: <87edhter7v.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.7 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@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_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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Paolo Bonzini writes: > On Mon, Oct 16, 2023 at 1:55=E2=80=AFPM Markus Armbruster wrote: >> Out of curiosity: what's a non-relocatable install, and why should I >> care? > > In a relocatable install if you move qemu-system-x86_64 from /usr/bin > to /home/armbru/bin, it will start looking for firmware in > /home/armbru/share/qemu. > > In a non-relocatable install, it will keep looking for firmware in > /usr/share/qemu. > > Whether that's something desirable or not... it depends. > > On POSIX systems you almost never notice. Non-relocatability can help > if you want to do experiments with old firmware and new QEMU or vice > versa (because you can just upgrade/downgrade the firmware package, > and use rpm2cpio to extract the QEMU binaries outside /usr). > > On the other hand Windows almost always wants relocatable installs, > which is why the whole idea was introduced in QEMU in fact. Newfangled > distribution mechanisms such as AppImage > (https://docs.appimage.org/reference/best-practices.html) and I think > NixOS (which installs each package in its own prefix, so you can > install multiple versions and switch at will the one that is symlinked > to /usr) also dislike using at runtime the absolute paths that were > established at build time. > > Finally, the same code that handles relocation also lets you run QEMU > from the build tree and pick e.g. firmware files from the source tree > transparently. Even with this patch, that part of the code remains > active even if you configure with --disable-relocatable. > > IOW: you probably have relied on the code, but if you have never > noticed in the past 3 years, it means that you probably need not care. I think this would make a fine commit message body :) Thanks!