Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751594AbWJWGRZ (ORCPT ); Mon, 23 Oct 2006 02:17:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751584AbWJWGRZ (ORCPT ); Mon, 23 Oct 2006 02:17:25 -0400 Received: from ug-out-1314.google.com ([66.249.92.171]:26078 "EHLO ug-out-1314.google.com") by vger.kernel.org with ESMTP id S1751577AbWJWGRY (ORCPT ); Mon, 23 Oct 2006 02:17:24 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=RyL3NsfgTz5mUeutx+sosxzSJEcIKcKPsMYNIv76TV7UkAkIaK2MfBXw4mF7ccXegK4W39jpQfuCEeCD6ppga0nR+EAus/CqxD8tvg59p23qaApFVMuqKjzSlyQHGEkmgs8PPHN/fVhAoLKF0TPZ22aLPDSIZ3U9lg7S6oNb1TU= Message-ID: <86802c440610222317l1867ab38v4c33231b96237b7f@mail.gmail.com> Date: Sun, 22 Oct 2006 23:17:23 -0700 From: yhlu To: "Eric W. Biederman" Subject: Re: [PATCH 2/2] x86_64 irq: Only look at per_cpu data for online cpus. Cc: "Andi Kleen" , "Muli Ben-Yehuda" , "Linux Kernel Mailing List" , "Andrew Morton" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <200610212100.k9LL0GtC018787@hera.kernel.org> <20061022035109.GM5211@rhun.haifa.ibm.com> <20061022085216.GQ5211@rhun.haifa.ibm.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1202 Lines: 26 On 10/22/06, Eric W. Biederman wrote: > > When I generalized __assign_irq_vector I failed to pay attention > to what happens when you access a per cpu data structure for > a cpu that is not online. It is an undefined case making any > code that does it have undefined behavior as well. > > The code still needs to be able to allocate a vector across cpus > that are not online to properly handle combinations like lowest > priority interrupt delivery and cpu_hotplug. Not that we can do > that today but the infrastructure shouldn't prevent it. > > So this patch updates the places where we touch per cpu data > to only touch online cpus, it makes cpu vector allocation > an atomic operation with respect to cpu hotplug, and it updates > the cpu start code to properly initialize vector_irq so we > don't have inconsistencies. > > Signed-off-by: Eric W. Biederman Acked-by: Yinghai Lu - 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/