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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5A7FEC433B4 for ; Fri, 14 May 2021 20:01:58 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id BDBA561042 for ; Fri, 14 May 2021 20:01:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BDBA561042 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bugs.launchpad.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:55972 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lhe0S-0003Ln-PY for qemu-devel@archiver.kernel.org; Fri, 14 May 2021 16:01:56 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35852) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lhdzN-0002ay-Uu for qemu-devel@nongnu.org; Fri, 14 May 2021 16:00:49 -0400 Received: from indium.canonical.com ([91.189.90.7]:49720) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1lhdzM-00006E-9m for qemu-devel@nongnu.org; Fri, 14 May 2021 16:00:49 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.93 #5 (Debian)) id 1lhdzK-0007xl-UZ for ; Fri, 14 May 2021 20:00:46 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id C32762E8186 for ; Fri, 14 May 2021 20:00:46 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Fri, 14 May 2021 19:55:06 -0000 From: Bruno Haible <1912934@bugs.launchpad.net> To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=New; importance=Undecided; assignee=None; X-Launchpad-Bug-Tags: ppc tcg X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: bruno-clisp th-huth X-Launchpad-Bug-Reporter: Bruno Haible (bruno-clisp) X-Launchpad-Bug-Modifier: Bruno Haible (bruno-clisp) References: <161147764119.28788.10484645020687886149.malonedeb@soybean.canonical.com> Message-Id: <162102210695.1637.8011684145245493053.malone@wampee.canonical.com> Subject: [Bug 1912934] Re: QEMU emulation of fmadds instruction on powerpc64le is buggy X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="5321c3f40fa4d4b847f4e47fb766e7b95ed5036c"; Instance="production" X-Launchpad-Hash: 369d61b91bc5f49ce75ea49f123461094d713b17 Received-SPF: none client-ip=91.189.90.7; envelope-from=bounces@canonical.com; helo=indium.canonical.com X-Spam_score_int: -65 X-Spam_score: -6.6 X-Spam_bar: ------ X-Spam_report: (-6.6 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.248, RCVD_IN_DNSWL_HI=-5, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1912934 <1912934@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The situation is still the same in QEMU 6.0.0. $ powerpc64le-linux-gnu-gcc-5 test-fmadds.c -static $ ~/inst-qemu/6.0.0/bin/qemu-ppc64le ./a.out ; echo $? 32 ** Changed in: qemu Status: Incomplete =3D> New -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1912934 Title: QEMU emulation of fmadds instruction on powerpc64le is buggy Status in QEMU: New Bug description: The attached program test-fmadds.c tests the fmadds instruction on powerpc64le. Result on real hardware (POWER8E processor): $ ./a.out ; echo $? 0 Result in Alpine Linux 3.13/powerpcle, emulated by QEMU 5.0.0 on Ubuntu 1= 6.04: $ ./a.out ; echo $? 32 Result in Debian 8.6.0/ppc64el, emulated by QEMU 2.9.0 on Ubuntu 16.04: $ ./a.out ; echo $? 32 Through 'nm --dynamic qemu-system-ppc64 | grep fma' I can see that QEMU is NOT using the fmaf() or fma() function from the host system's libc; this function is working fine in glibc of the host system (see https://www.gnu.org/software/gnulib/manual/html_node/fmaf.html ). To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1912934/+subscriptions