From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mga02.intel.com ([134.134.136.20]) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Xj5hp-0000q1-R8 for kexec@lists.infradead.org; Tue, 28 Oct 2014 12:16:58 +0000 Date: Tue, 28 Oct 2014 05:16:36 -0700 From: Andi Kleen Subject: Re: [PATCH V4] kernel, add bug_on_warn Message-ID: <20141028121636.GC3274@tassilo.jf.intel.com> References: <1414155207-29839-1-git-send-email-prarit@redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1414155207-29839-1-git-send-email-prarit@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Prarit Bhargava Cc: Jonathan Corbet , kexec@lists.infradead.org, jason.wessel@windriver.com, Rusty Russell , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Fabian Frederick , isimatu.yasuaki@jp.fujitsu.com, "H. Peter Anvin" , Masami Hiramatsu , Andrew Morton , linux-api@vger.kernel.org, vgoyal@redhat.com On Fri, Oct 24, 2014 at 08:53:27AM -0400, Prarit Bhargava wrote: > There have been several times where I have had to rebuild a kernel to > cause a panic when hitting a WARN() in the code in order to get a crash > dump from a system. Sometimes this is easy to do, other times (such as > in the case of a remote admin) it is not trivial to send new images to the > user. > > A much easier method would be a switch to change the WARN() over to a > BUG(). This makes debugging easier in that I can now test the actual > image the WARN() was seen on and I do not have to engage in remote > debugging. IMHO this would be better and far more generically done with kdb. You would need two things: - Extend the break point command to run another command on a break point. - Add a command line (or possibly /proc) option to execute some kdb commands at kernel boot. Then just set a break point on the warn function and execute magic sysrq c from kdb. -Andi _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec