From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753957AbbFASkS (ORCPT ); Mon, 1 Jun 2015 14:40:18 -0400 Received: from mail.kernel.org ([198.145.29.136]:32865 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753909AbbFASkL (ORCPT ); Mon, 1 Jun 2015 14:40:11 -0400 Message-ID: <556CA704.1070000@kernel.org> Date: Mon, 01 Jun 2015 11:40:04 -0700 From: Andy Lutomirski User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Len Brown , x86@kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org CC: Len Brown Subject: Re: [PATCH 1/1] x86 TSC: set X86_FEATURE_TSC_RELIABLE, per CPUID References: In-Reply-To: Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05/30/2015 10:44 PM, Len Brown wrote: > From: Len Brown > > Speed cpu_up() by believing CPUID's "invariant TSC" flag, > and skipping the TSC warp test on single socket systems. I'm typing this email on a "Intel(R) Core(TM) i7-3930K CPU @ 3.20GHz" with a "X79A-GD65 (8D) (MS-7760)" motherboard. (DO NOT BUY THAT MOTHERBOARD!) The brilliant stock firmware breaks TSC sync on bootup. Even with the updated firmware I'm using, it's broken on resume from S3. If you want to make this depend on X86_FEATURE_TSC_ADJUST and confirm that all cores have the same IA32_TSC_ADJUST value, then maybe that would be okay. Otherwise, please don't underestimate the malice^Wgross incompetence of firmware vendors. --Andy