Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753351AbYCTKjU (ORCPT ); Thu, 20 Mar 2008 06:39:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751522AbYCTKjJ (ORCPT ); Thu, 20 Mar 2008 06:39:09 -0400 Received: from cerber.ds.pg.gda.pl ([153.19.208.18]:33722 "EHLO cerber.ds.pg.gda.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751510AbYCTKjH (ORCPT ); Thu, 20 Mar 2008 06:39:07 -0400 X-Greylist: delayed 597 seconds by postgrey-1.27 at vger.kernel.org; Thu, 20 Mar 2008 06:39:07 EDT Date: Thu, 20 Mar 2008 10:28:58 +0000 (GMT) From: "Maciej W. Rozycki" X-X-Sender: macro@piorun To: Glauber de Oliveira Costa cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, tglx@linutronix.de, mingo@elte.hu, ak@suse.de Subject: Re: [PATCH 45/79] [PATCH] fix apic acking of irqs In-Reply-To: <12059477792893-git-send-email-gcosta@redhat.com> Message-ID: References: <12059475744092-git-send-email-gcosta@redhat.com> <12059476844196-git-send-email-gcosta@redhat.com> <12059476883852-git-send-email-gcosta@redhat.com> <12059476932397-git-send-email-gcosta@redhat.com> <12059476971309-git-send-email-gcosta@redhat.com> <1205947702588-git-send-email-gcosta@redhat.com> <12059477063046-git-send-email-gcosta@redhat.com> <12059477102394-git-send-email-gcosta@redhat.com> <12059477143205-git-send-email-gcosta@redhat.com> <1205947719906-git-send-email-gcosta@redhat.com> <12059477234148-git-send-email-gcosta@redhat.com> <12059477273855-git-send-email-gcosta@redhat.com> <1205947732309-git-send-email-gcosta@redhat.com> <12059477371787-git-send-email-gcosta@redhat.com> <12059477421707-git-send-email-gcosta@redhat.com> <12059477472416-git-send-email-gcosta@redhat.com> <12059477521176-git-send! -email-gcosta@redhat.com> <12059477561937-git-send-email-gcosta@redhat <12059477792893-git-send-email-gcosta@redhat.com> User-Agent: Alpine 1.00 (SOC 882 2007-12-20) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 844 Lines: 18 On Wed, 19 Mar 2008, Glauber de Oliveira Costa wrote: > EOI is a write-only register. Using write around will have the effect > of reading it, which will make all subsequent reads of the ESR register > to return an error code. It was unnotices for quite a while because main sources > of reading the ESR register where done prior to apic interrupt enabling. Are you sure this actually triggers for APIC chips affected by the erratum in question? And please note that for them the effect of two consecutive writes will be much more disastrous than setting a bit in the ESR register. Maciej -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/