From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758808AbZGIH5L (ORCPT ); Thu, 9 Jul 2009 03:57:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751452AbZGIH5A (ORCPT ); Thu, 9 Jul 2009 03:57:00 -0400 Received: from viefep19-int.chello.at ([62.179.121.39]:55404 "EHLO viefep19-int.chello.at" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751332AbZGIH47 (ORCPT ); Thu, 9 Jul 2009 03:56:59 -0400 X-SourceIP: 213.93.53.227 Subject: Re: [PATCH] netpoll: Fix carrier detection for drivers that are using phylib From: Peter Zijlstra To: Linus Torvalds Cc: Anton Vorontsov , Andrew Morton , oleg@redhat.com, mingo@elte.hu, linux-kernel@vger.kernel.org, netdev@vger.kernel.org In-Reply-To: References: <20090707235812.GA12824@oksana.dev.rtsoft.ru> <20090708005000.GA12380@redhat.com> <1247034263.9777.24.camel@twins> <20090708141024.f8b581c5.akpm@linux-foundation.org> <20090708213331.GA9346@oksana.dev.rtsoft.ru> <20090708144744.5555b88d.akpm@linux-foundation.org> <20090708222003.GA12318@oksana.dev.rtsoft.ru> Content-Type: text/plain Date: Thu, 09 Jul 2009 09:56:50 +0200 Message-Id: <1247126210.9777.317.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.26.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2009-07-08 at 17:01 -0700, Linus Torvalds wrote: > Looking at the people looking at SYSTEM_RUNNING, I do note some odd cases. > Why the heck does kernel/perf_counter.c do it, for example? Ah, those are the swcounter and other probe entry points. I've had several cases where we called into the perf counter code from those points before it was initialized, getting in kernel segfaults due to dereferencing uninitialized data etc.. I could keep a variable that tracked the perf_counter_init() state, and use that instead if you prefer?