From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754126AbWKHEHZ (ORCPT ); Tue, 7 Nov 2006 23:07:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754135AbWKHEHZ (ORCPT ); Tue, 7 Nov 2006 23:07:25 -0500 Received: from smtp.osdl.org ([65.172.181.4]:38634 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1754126AbWKHEHY (ORCPT ); Tue, 7 Nov 2006 23:07:24 -0500 Date: Tue, 7 Nov 2006 20:07:02 -0800 From: Andrew Morton To: "Siddha, Suresh B" Cc: ak@suse.de, shaohua.li@intel.com, linux-kernel@vger.kernel.org, discuss@x86-64.org, ashok.raj@intel.com Subject: Re: [patch 0/4] i386, x86_64: fix the irqbalance quirk for E7520/E7320/E7525 Message-Id: <20061107200702.8abac851.akpm@osdl.org> In-Reply-To: <20061107173306.C3262@unix-os.sc.intel.com> References: <20061107173306.C3262@unix-os.sc.intel.com> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 7 Nov 2006 17:33:06 -0800 "Siddha, Suresh B" wrote: > Mechanism of selecting physical mode in genapic when cpu hotplug is enabled > on x86_64, broke the quirk(quirk_intel_irqbalance()) introduced for working > around the transposing interrupt message errata in E7520/E7320/E7525 > (revision ID 0x9 and below. errata #23 in > http://download.intel.com/design/chipsets/specupdt/30304203.pdf). > > This errata requires the mode to be in logical flat, so that interrupts > can be directed to more than one cpu(and thus use hardware IRQ balancing > enabled by BIOS on these platforms). > > Following four patches fixes this by moving the quirk to early quirk > and forcing the x86_64 genapic selection to logical flat on these platforms. > > Thanks to Shaohua for pointing out the breakage. It blew up with the first config I tried (http://userweb.kernel.org/~akpm/config-vmm.txt): arch/i386/kernel/built-in.o: In function `verify_quirk_intel_irqbalance': arch/i386/kernel/quirks.c:19: undefined reference to `genapic' arch/i386/kernel/quirks.c:19: undefined reference to `apic_default' arch/i386/kernel/built-in.o: In function `__cpu_up': arch/i386/kernel/smpboot.c:1487: undefined reference to `genapic' arch/i386/kernel/smpboot.c:1487: undefined reference to `apic_default' The dependencies in the code which you're touching here are really really complex and fragile. One needs to review the change very carefully and test it exhaustively.