From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758521AbbCDOO2 (ORCPT ); Wed, 4 Mar 2015 09:14:28 -0500 Received: from v094114.home.net.pl ([79.96.170.134]:62772 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1753254AbbCDOO1 (ORCPT ); Wed, 4 Mar 2015 09:14:27 -0500 From: "Rafael J. Wysocki" To: Borislav Petkov Cc: Arjan van de Ven , Ingo Molnar , "Li, Aubrey" , "alan@linux.intel.com" , "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , Len.Brown@intel.com, x86@kernel.org, LKML Subject: Re: [PATCH] x86: Bypass legacy PIC and PIT on ACPI hardware reduced platform Date: Wed, 04 Mar 2015 15:38:02 +0100 Message-ID: <11431611.orMBdoggXx@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.19.0+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <20150304140555.GG3516@pd.tnic> References: <54F67ACC.3010500@linux.intel.com> <8773039.WD3UIoUtJl@vostro.rjw.lan> <20150304140555.GG3516@pd.tnic> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday, March 04, 2015 03:05:55 PM Borislav Petkov wrote: > On Wed, Mar 04, 2015 at 03:16:07PM +0100, Rafael J. Wysocki wrote: > > Sort of. What we need is a "do not touch PIC/PIT" bit for the code that > > tries to fall back to them in some cases (which may appear to work if > > the hardware is physically there, but it may confuse the platform). > > Can "some cases" detection be nicely put into a x86_platform > platform-specific method? I guess so. The problem is that we just do that fallback unconditionally today which evidently doesn't always work.