From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mp0 ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by ms11 with LMTPS id AHENE7v1Q2DJHAAA0tVLHw (envelope-from ) for ; Sat, 06 Mar 2021 21:35:55 +0000 Received: from aspmx1.migadu.com ([2001:41d0:2:4a6f::]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) by mp0 with LMTPS id gO7cDrv1Q2ChDAAA1q6Kng (envelope-from ) for ; Sat, 06 Mar 2021 21:35:55 +0000 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 aspmx1.migadu.com (Postfix) with ESMTPS id 63B9412478 for ; Sat, 6 Mar 2021 22:35:54 +0100 (CET) Received: from localhost ([::1]:46096 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lIeaX-0006b5-F2 for larch@yhetil.org; Sat, 06 Mar 2021 16:35:53 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:56528) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lIeaF-0006aK-6m for guix-devel@gnu.org; Sat, 06 Mar 2021 16:35:35 -0500 Received: from mira.cbaines.net ([2a01:7e00:e000:2f8:fd4d:b5c7:13fb:3d27]:56113) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lIeaB-0002pM-4U for guix-devel@gnu.org; Sat, 06 Mar 2021 16:35:34 -0500 Received: from localhost (unknown [IPv6:2a02:8010:68c1:0:8ac0:b4c7:f5c8:7caa]) by mira.cbaines.net (Postfix) with ESMTPSA id 488F827BC50 for ; Sat, 6 Mar 2021 21:35:29 +0000 (GMT) Received: from capella (localhost [127.0.0.1]) by localhost (OpenSMTPD) with ESMTP id ebe906fc for ; Sat, 6 Mar 2021 21:35:27 +0000 (UTC) User-agent: mu4e 1.4.15; emacs 27.1 From: Christopher Baines To: guix-devel@gnu.org Subject: Implications of QEMU binfmt transparent emulation for builds Date: Sat, 06 Mar 2021 21:35:24 +0000 Message-ID: <87eegsnexv.fsf@cbaines.net> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" Received-SPF: pass client-ip=2a01:7e00:e000:2f8:fd4d:b5c7:13fb:3d27; envelope-from=mail@cbaines.net; helo=mira.cbaines.net X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: guix-devel@gnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: "Development of GNU Guix and the GNU System distribution." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: guix-devel-bounces+larch=yhetil.org@gnu.org Sender: "Guix-devel" X-Migadu-Flow: FLOW_IN ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=yhetil.org; s=key1; t=1615066554; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:mime-version:mime-version: content-type:content-type:list-id:list-help:list-unsubscribe: list-subscribe:list-post; bh=2P/FcIpVlvUVCpznmEm+iJE9sBFWPbyhk+ygd09VuX0=; b=mvz135aQ8b9ium3ogtKgZ48A/DXJHqeLKYDwz2UbIcWbi12Bx0v7KBkSPEuT4NBj39T27L ok1BRSQlg0gusBazjCgConBfBqgqfhgYhp9RxlEGyjj5tXkdMNkRfJnMuc3zn8sc5Dm3ki la3j6/RLa+Ncb34mXm+Nbjn6MX3rMsknA/PvMYPZa8fMDJIb0YWlVlsfoa0UWiWyLIjvK/ NwAayi9zgjXtFnHd9UyLXr/PUVnAPKE1bui2dnP+PCS7ZyEy6IPcW+fYpwkSpNJIZZNx2U ydgybeFi7Wh991ba+KmRLlzvLfRZHXx2jRl872fm9o4H7MmIOHDuxoQ/mduEjw== ARC-Seal: i=1; s=key1; d=yhetil.org; t=1615066554; a=rsa-sha256; cv=none; b=IIslkHHNT5Ijyjn5Mby/Ffd29ZohsIH/m+bXxwBQsjsDOFG5yzbMwaaWg7obfYkif/fGE6 ZZB9j0Ao7i/H896cKEsD5BWs3JLBG7fC92vr8iMmlP35sBblI2vki8s9X1jaAgXIAwkUYs 4AcZrkSNkjy6CvQdy5n2quSXRepe6vz50ycj/1IJO4DQmTg6fIw1zbyI3XIk8b+ad/R2fy rwjw2Yw5/cZQNbEtyjnP1gEqJ21n7RYjzb7Kw/6/qDvGJtbMc3TfF3u0vYPgzYiRkTxw94 VqwTTzjBzA2fW9ey779q/nRGOWSPIHuTo8HPL2eMyE8q/JbfWg5fwnm8jrMn0w== ARC-Authentication-Results: i=1; aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of guix-devel-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=guix-devel-bounces@gnu.org X-Migadu-Spam-Score: -4.47 Authentication-Results: aspmx1.migadu.com; dkim=none; dmarc=none; spf=pass (aspmx1.migadu.com: domain of guix-devel-bounces@gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=guix-devel-bounces@gnu.org X-Migadu-Queue-Id: 63B9412478 X-Spam-Score: -4.47 X-Migadu-Scanner: scn1.migadu.com X-TUID: DUIY6/yJTVq+ --=-=-= Content-Type: text/plain Hey, I'm starting to play with mixing native and emulated builds with the Guix Build Coordinator again. I did do this many months ago, but at that time, there wasn't support for targeting retries across a range of machines, to help avoid blockages due to QEMU issues. Anyway, something that's been on my mind regarding QEMU and builds is how well this matches up with building natively. In particular, I'm concerned that there are some derivations that will build on system A with some QEMU configuration allowing binaries for system B to be run, but won't build if that QEMU support wasn't there. I think there's also a chance that you could have a derivation for system A that builds on a system with QEMU support for system B, but then wouldn't build natively on system B. I think the first scenario is more likely, mainly because I wonder if this happens with cross built packages. If the package attempts to run software built for the target system, that will work if there's QEMU support there for that target system, but not if that QEMU support is lacking. This is just a theory at this point, I at least don't know of any cases of this happening, but I also haven't been looking. Any ideas? I'd like the Guix Build Coordinator agents to be able to report the configuration of the machine at the time builds happen, so maybe once that's a feature, and QEMU support can be detected, then it'll be possible to look for cases where a change in QEMU support affects the build result. I've been thinking about this lately because I'd like to maybe use QEMU to help build things for aarch64-linux and armhf-linux, but I don't want to do something that could impact x86_64-linux derivations building for other architectures (which guix.cbaines.net does do). Thanks, Chris --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQKlBAEBCgCPFiEEPonu50WOcg2XVOCyXiijOwuE9XcFAmBD9ZxfFIAAAAAALgAo aXNzdWVyLWZwckBub3RhdGlvbnMub3BlbnBncC5maWZ0aGhvcnNlbWFuLm5ldDNF ODlFRUU3NDU4RTcyMEQ5NzU0RTBCMjVFMjhBMzNCMEI4NEY1NzcRHG1haWxAY2Jh aW5lcy5uZXQACgkQXiijOwuE9XdPlw/+Pzv3CCIz4/cJeCXQ6a/+JcKYYOX43uxs rztyigswNtJyJLk9wukROsiFIbi4FKAbFvb7hL9fX88dj1i2ljw4MVdDYUnpxWb2 e8oFT7SsVccAroTIJBWl/Ee2iJRuMaZ/NwQUVBI+mU50jUCNAzcsuhQ1KwgsRTku /1Cqqok7knNUMXX+dI/ELUpiLRRa4o8TgtRhmuAo+b08gmtCvdN8c/eZsSrXCD8h nlZyYY28+sI6mvFKx5Y12/f80j6b8NUP22xL41w8yHvdFiGTvgG8HumP5J4324RX NjVTTMdLcz+YcATD6Z/Q9nwV1xodNnJdw5Oho3tRsrpaqR7bv68DSKJa8T8ZoHZF d08IwZ9q2wdmtGNXmsrb4RaUF10hKQAJN3DFEtK2Do/r0ST0yc2t2ov7E1fuXsws UWp/ReMXWjA4zlHG5nbCva22VseIfQbnmFSp5VSnYMtN5h8ZdGJgfN7w+UuLcR7F kqCxDdyoDMhr1B2c4LFiWIff7G9ZEOuJcRYhk1NI1AFNsnHbVlVkSBYuTBNh9fs2 jtIxA457UxiT2mgtWGyUNGaTPysN3vvKRvGaJBImFrdkKv5DHhEGHFXA/CK03NlN acxK4H5OQ3lkJf0aNZ7ABKTfxmBWBsgfR0ZBZBrzASnOin71xr9Cnn+C9uS6sYMx d3mff+vasr8= =Y9xt -----END PGP SIGNATURE----- --=-=-=--