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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D3CD3C04A95 for ; Sat, 22 Oct 2022 21:29:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229894AbiJVV34 (ORCPT ); Sat, 22 Oct 2022 17:29:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51756 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229744AbiJVV3z (ORCPT ); Sat, 22 Oct 2022 17:29:55 -0400 X-Greylist: delayed 1153 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Sat, 22 Oct 2022 14:29:48 PDT Received: from terminus.zytor.com (unknown [IPv6:2607:7c80:54:3::136]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42F432A95C; Sat, 22 Oct 2022 14:29:45 -0700 (PDT) Received: from [127.0.0.1] ([73.223.250.219]) (authenticated bits=0) by mail.zytor.com (8.17.1/8.17.1) with ESMTPSA id 29ML8eEF2420262 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Sat, 22 Oct 2022 14:08:40 -0700 DKIM-Filter: OpenDKIM Filter v2.11.0 mail.zytor.com 29ML8eEF2420262 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=zytor.com; s=2022100601; t=1666472925; bh=6+RY9iRcpIT3J7CLCZno8RRf3RLOv3Q087OMBJ+x97E=; h=Date:From:To:CC:Subject:In-Reply-To:References:From; b=ua66S0skPTe1vO2SZSgS2viQ/FflA40OHsC3Pj6699LV7Bi5V/d4NdVcSlOqA15Yn Nxm+uQeMGlSaUqJ/UCCEnLlIQypZc8URTE/hnB9O4RElzY8oWyusHAZz+Big61WNVW jKkHpNeZOqeT0AwMD9RpBbQ+H/skXhgNMWlz4jvAKEZrm2PTg4L7BywspYB4c9QL62 nhjMptrmaBHP98aAzh+knOS3p4JrTDZ/pZNm/n0YPcMp20ttKwmBF1BTTw4u/WY9dq 5GEHlfxQWApwWVJ7xHiyQr7b43sUqLOFqnD1YuYPQef4GAupHNcFBvO/Xb1Vs1wwBz p/E3WpuQTLe2Q== Date: Sat, 22 Oct 2022 14:08:37 -0700 From: "H. Peter Anvin" To: Borislav Petkov , Maxim Levitsky CC: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, Pawan Gupta , Ingo Molnar , Josh Poimboeuf , Namhyung Kim , Tony Luck , Paolo Bonzini , Arnaldo Carvalho de Melo , Thomas Gleixner , Alexander Shishkin , Tim Chen , "David S. Miller" , Dave Hansen , "Chang S. Bae" , Jane Malalane , Kees Cook , Kan Liang , Peter Zijlstra , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Herbert Xu , Jiri Olsa , Mark Rutland , linux-perf-users@vger.kernel.org, "open list:CRYPTO API" Subject: =?US-ASCII?Q?Re=3A_=5BPATCH_v2_1/5=5D_perf/x86/intel/lbr=3A_use_?= =?US-ASCII?Q?setup=5Fclear=5Fcpu=5Fcap_instead_of_clear=5Fcpu=5Fcap?= User-Agent: K-9 Mail for Android In-Reply-To: References: <20220718141123.136106-1-mlevitsk@redhat.com> <20220718141123.136106-2-mlevitsk@redhat.com> Message-ID: <892F8AE5-9FF9-4452-A6A7-A130C49D0C51@zytor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On October 20, 2022 1:59:48 AM PDT, Borislav Petkov wrote: >On Wed, Sep 28, 2022 at 01:49:34PM +0300, Maxim Levitsky wrote: >> Patch 5 is the main fix - it makes the kernel to be tolerant to a >> broken CPUID config (coming hopefully from hypervisor), where you have >> a feature (AVX2 in my case) but not a feature on which this feature >> depends (AVX)=2E > >I really really don't like it when people are fixing the wrong thing=2E > >Why does the kernel need to get fixed when something else can't get its >CPUID dependencies straight? I don't even want to know why something >would set AVX2 without AVX?!?! > >Srsly=2E > >Some of your other bits look sensible and I'd take a deeper look but >this does not make any sense=2E This is a hypervisor problem - not a >kernel one=2E > >Thx=2E > Yes, this is utterly nonsensical and it will break user space applications= left, right, and center=2E