From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id 1FFFAA00E6 for ; Tue, 16 Apr 2019 17:47:17 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 94D491B4FE; Tue, 16 Apr 2019 17:47:16 +0200 (CEST) Received: from mga06.intel.com (mga06.intel.com [134.134.136.31]) by dpdk.org (Postfix) with ESMTP id 87D2D1B4F7; Tue, 16 Apr 2019 17:47:15 +0200 (CEST) X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Apr 2019 08:47:14 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,358,1549958400"; d="scan'208";a="162099940" Received: from bricha3-mobl.ger.corp.intel.com ([10.237.220.103]) by fmsmga002.fm.intel.com with SMTP; 16 Apr 2019 08:47:11 -0700 Received: by (sSMTP sendmail emulation); Tue, 16 Apr 2019 16:47:11 +0100 Date: Tue, 16 Apr 2019 16:47:10 +0100 From: Bruce Richardson To: Ferruh Yigit Cc: Thomas Monjalon , John McNamara , Marko Kovacevic , dev@dpdk.org, stable@dpdk.org Message-ID: <20190416154710.GA1879@bricha3-MOBL.ger.corp.intel.com> References: <20190410140058.26782-1-ferruh.yigit@intel.com> <20190416153932.21788-1-ferruh.yigit@intel.com> <20190416153932.21788-2-ferruh.yigit@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline In-Reply-To: <20190416153932.21788-2-ferruh.yigit@intel.com> User-Agent: Mutt/1.11.4 (2019-03-13) Subject: Re: [dpdk-dev] [PATCH v2 2/2] build: fix crash by disabling AVX512 with binutils 2.31 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Message-ID: <20190416154710.ZZKBpch8CRPeriyUbef6pjNagZNA0WO295ABFcH0mo8@z> On Tue, Apr 16, 2019 at 04:39:32PM +0100, Ferruh Yigit wrote: > On Skylake platform, with native build, KNI kernel module crashes > because of the corrupted values passed to kernel module. > > The corruption occurs because the userspace kni library works > unexpectedly. Compiler [1] is using AVX512 instructions and generated > binary is wrong [2]. > > It turned around gcc does its job correct, but gas is generating binary > wrong. And expected binutils 2.30, 2.31 & 2.31.1 are affected. Issue has > been fixed in binutils 2.32 with: > Commit x86: don't mistakenly scale non-8-bit displacements > > AVX512 was already disabled with bintuils 2.30 [3], extending it to > 2.31 & 2.31.1 too. > > [1] gcc (GCC) 8.3.1 20190223 (Red Hat 8.3.1-2) > > [2] gcc bug: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90028 > > [3] Bugzilla ID 97 has the details. > > Bugzilla ID: 249 > Cc: stable@dpdk.org > > Signed-off-by: Ferruh Yigit > --- > v2: > * Release notes "Known Issues" section updated > --- > config/x86/meson.build | 6 ++++++ > doc/guides/rel_notes/release_19_05.rst | 6 ++++++ > mk/toolchain/gcc/rte.toolchain-compat.mk | 9 ++++++++- > 3 files changed, 20 insertions(+), 1 deletion(-) > > diff --git a/config/x86/meson.build b/config/x86/meson.build > index 692aebe7a..9e9d5dc8c 100644 > --- a/config/x86/meson.build > +++ b/config/x86/meson.build > @@ -10,6 +10,12 @@ if host_machine.system() != 'windows' > message('Binutils 2.30 detected, disabling AVX512 support as workaround for bug #97') > endif > endif > + if ldver.contains('2.31') > + if cc.has_argument('-mno-avx512f') > + machine_args += '-mno-avx512f' > + message('Binutils 2.31 detected, disabling AVX512 support as workaround for bug #249') > + endif > + endif Is this not the same as the previous block just with a slightly different error message? Should we merge the two, and print out both bug numbers? If not merging, we can reduce the indentation by putting the second cc.has_argument() condition on the same line as the previous check, i.e. "if ldver.contains(...) and cc.has_argument(...)" Apart from this nit: Acked-by: Bruce Richardson