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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 3A7E4C31E46 for ; Wed, 12 Jun 2019 04:03:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 122AE2086A for ; Wed, 12 Jun 2019 04:03:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="lI2ow/OD" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726145AbfFLEDE (ORCPT ); Wed, 12 Jun 2019 00:03:04 -0400 Received: from mail.skyhub.de ([5.9.137.197]:54448 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725994AbfFLEDD (ORCPT ); Wed, 12 Jun 2019 00:03:03 -0400 Received: from zn.tnic (p200300EC2F0A680098854F45E2A0A47F.dip0.t-ipconnect.de [IPv6:2003:ec:2f0a:6800:9885:4f45:e2a0:a47f]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 16ED61EC0467; Wed, 12 Jun 2019 06:03:02 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1560312182; 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:in-reply-to:in-reply-to: references:references; bh=s5hOtfFPgTiY8jVIYZGW21WLJ7BpwUhn+HZQo+5wkro=; b=lI2ow/ODPtiKcdMEX/i4VTcbA+F5/I+XzJbBbEMe3YJOkzdb6dI5aSkou4gX1PyG5Geoad KjmBl64czu6LR/j6cxbXtK37erJFLyEzbNX/yhFP8rJ1aJhH3lJBwZJgevD9gpuvY1RW30 NSQNduiXK+/+j43d3ZLoI37v2yhbqqo= Date: Wed, 12 Jun 2019 06:02:59 +0200 From: Borislav Petkov To: Fenghua Yu Cc: Thomas Gleixner , Ingo Molnar , H Peter Anvin , Ravi V Shankar , linux-kernel , x86 Subject: Re: [RFC PATCH] x86/cpufeatures: Enumerate new AVX512 bfloat16 instructions Message-ID: <20190612040259.GC32652@zn.tnic> References: <1560186158-174788-1-git-send-email-fenghua.yu@intel.com> <20190610192026.GI5488@zn.tnic> <20190611181920.GC180343@romley-ivt3.sc.intel.com> <20190611194701.GJ31772@zn.tnic> <20190612033259.GE180343@romley-ivt3.sc.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190612033259.GE180343@romley-ivt3.sc.intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 11, 2019 at 08:32:59PM -0700, Fenghua Yu wrote: > Currently KVM doesn't simulate scattered features (the ones in CPUID_LNX_* > in cpuid_leafs) as reverse_cpuid[] doesn't contain CPUID_LNX_*. 43500e6f294d ("x86/cpufeatures: Remove get_scattered_cpuid_leaf()") > After the X86_FEATURES_CQM_* features are changed to scattered features, > they will not be simulated by KVM any more as CPUID_F_0_EDX and CPUID_F_1_EDX > are removed. Does KVM even support resctrl? I doubt only exporting a couple of CPUID bits into the guest is enough... > Should patch #1 simulate X86_FEATURE_CQM_* in KVM? Or let KVM guys handle > the scattered features? Right, the scattered thing was removed as KVM didn't need it, apparently, see above. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.