From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752924AbaCMC5q (ORCPT ); Wed, 12 Mar 2014 22:57:46 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:43673 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752409AbaCMC5p (ORCPT ); Wed, 12 Mar 2014 22:57:45 -0400 Subject: Re: [RESEND] Fast TSC calibration fails with v3.14-rc1 and later From: joeyli To: Thomas Gleixner , "Rafael J. Wysocki" Cc: Julian Wollrath , x86@kernel.org, LKML , "Rafael J. Wysocki" , "H. Peter Anvin" In-Reply-To: References: <20140310110410.5b2218f6@ilfaris> <1554867.utJVyPuT6A@vostro.rjw.lan> Content-Type: text/plain; charset="UTF-8" Date: Thu, 13 Mar 2014 10:56:56 +0800 Message-ID: <1394679416.26565.220.camel@linux-s257.site> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 於 四,2014-03-13 於 00:49 +0100,Thomas Gleixner 提到: > On Thu, 13 Mar 2014, Rafael J. Wysocki wrote: > > I agree, and we need to fix that for 3.14. Patch is appended. > > You beat me by a few minutes. Was about to send out the same, just > with a more spicy changelog :) > > > --- > > From: Rafael J. Wysocki > > Subject: ACPI / init: Invoke early ACPI initialization later > > > > Commit 73f7d1ca3263 (ACPI / init: Run acpi_early_init() before > > timekeeping_init()) optimistically moved the early ACPI initialization > > before timekeeping_init(), but that didn't work, because it broke fast > > TSC calibration for Julian Wollrath on Thinkpad x121e (and most likely > > for others too). The reason is that acpi_early_init() enables the SCI > > and that interferes with the fast TSC calibration mechanism. > > > > Thus follow the original idea to execute acpi_early_init() before > > efi_enter_virtual_mode() to help the EFI people for now and we can > > revisit the other problem that commit 73f7d1ca3263 attempted to > > address in the future (if really necessary). > > Reviewed-by: Thomas Gleixner > > Acked-by: Lee, Chun-Yi Thanks a lot! Joey Lee