From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [PATCH] x86 ACPI: Fix breakage of resume on 64-bit UP systems with SMP kernel Date: Fri, 17 Oct 2008 10:37:00 +0200 Message-ID: <20081017083646.GA25445@elf.ucw.cz> References: <200810170126.27890.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from gprs189-60.eurotel.cz ([160.218.189.60]:38234 "EHLO gprs189-60.eurotel.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751666AbYJQIfb (ORCPT ); Fri, 17 Oct 2008 04:35:31 -0400 Content-Disposition: inline In-Reply-To: <200810170126.27890.rjw@sisk.pl> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: Ingo Molnar , ACPI Devel Maling List , Andrew Morton , LKML , pm list On Fri 2008-10-17 01:26:27, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > x86 ACPI: Fix breakage of resume on 64-bit UP systems with SMP kernel > > We are now using per CPU GDT tables in head_64.S and the original > early_gdt_descr.address is invalidated after boot by > setup_per_cpu_areas(). This breaks resume from suspend to RAM on > x86_64 UP systems using SMP kernels, because this part of head_64.S > is also executed during the resume and the invalid GDT address > causes the system to crash. It doesn't break on 'true' SMP systems, > because early_gdt_descr.address is modified every time > native_cpu_up() runs. However, during resume it should point to the > GDT of the boot CPU rather than to another CPU's GDT. > > For this reason, during suspend to RAM always make > early_gdt_descr.address point to the boot CPU's GDT. > > This fixes http://bugzilla.kernel.org/show_bug.cgi?id=11568, which > is a regression from 2.6.26. > > Signed-off-by: Rafael J. Wysocki > Reported-and-tested-by: Andy Wettstein Acked-by: Pavel Machek Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html