From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754035AbcDYIYq (ORCPT ); Mon, 25 Apr 2016 04:24:46 -0400 Received: from www.linutronix.de ([62.245.132.108]:59682 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753663AbcDYIYn (ORCPT ); Mon, 25 Apr 2016 04:24:43 -0400 Date: Mon, 25 Apr 2016 10:22:59 +0200 (CEST) From: Thomas Gleixner To: Lianwei Wang cc: Peter Zijlstra , oleg@redhat.com, Ingo Molnar , linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org Subject: Re: [PATCH] cpu/hotplug: handle unbalanced hotplug enable/disable In-Reply-To: Message-ID: References: <1461214567-3356-1-git-send-email-lianwei.wang@gmail.com> <20160421105042.GI3408@twins.programming.kicks-ass.net> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 22 Apr 2016, Lianwei Wang wrote: > Any way is Ok for debugging purpose. But think the kernel run on a > customer machine, such as PC, Mobile phone or other devices. How we > let the customer debug it but not recover it smartly? There is nothing smart here. Restoring the count is a bandaid and has nothing to do with recovery. If that WARN_ON triggers then other stuff is going to be more fundamentally wrong so restoring the count is the least of our worries. > Anyway, from a product perspective way, if we don't want to restore > the unbalanced counter to 0, then maybe a BUG_ON is more reasonable > than WARN_ON. Not at all. BUG_ON is the last resort if we have no other way to handle an issue. Thanks, tglx