Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932636AbaGAOXR (ORCPT ); Tue, 1 Jul 2014 10:23:17 -0400 Received: from mail.windriver.com ([147.11.1.11]:45515 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754297AbaGAOXP (ORCPT ); Tue, 1 Jul 2014 10:23:15 -0400 Message-ID: <53B2C419.4090706@windriver.com> Date: Tue, 1 Jul 2014 09:22:17 -0500 From: Jason Wessel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Daniel Thompson CC: , , , Mike Travis , Randy Dunlap , Dimitri Sivanich , Andrew Morton , Borislav Petkov , Subject: Re: [RFC PATCH] kgdb: Timeout if secondary CPUs ignore the roundup References: <1404224174-25024-1-git-send-email-daniel.thompson@linaro.org> In-Reply-To: <1404224174-25024-1-git-send-email-daniel.thompson@linaro.org> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/01/2014 09:16 AM, Daniel Thompson wrote: > Currently if an active CPU fails to respond to a roundup request the > CPU that requested the roundup will become stuck. This needlessly > reduces the robustness of the debugger. > > This patch introduces a timeout allowing the system state to be examined > even when the system contains unresponsive processors. It also modifies > kdb's cpu command to make it censor attempts to switch to unresponsive > processors and to report their state as (D)ead. It seems reasonable to allow entry on the master core because there certainly could be useful information to be had with respect to how you got there in the first place, but I wonder about the case for resuming the system. In general if you couldn't sync in the the first place, the system is dead. My opinion is that we probably should explicitly disallow a resume or single step at that point. Jason. -- 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/