From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from relay1.sgi.com ([192.48.171.29] helo=relay.sgi.com) by bombadil.infradead.org with esmtp (Exim 4.68 #1 (Red Hat Linux)) id 1Kd5hM-0007C7-Bi for kexec@lists.infradead.org; Tue, 09 Sep 2008 16:04:16 +0000 Message-ID: <48C69E4C.2020805@sgi.com> Date: Tue, 09 Sep 2008 09:03:24 -0700 From: Jay Lan MIME-Version: 1.0 Subject: Re: IA64: copying /proc/vmcore caused kernel MCA'ed References: <48C56F55.5000503@sgi.com> <20080909101900.76f843ec@kepler.site> In-Reply-To: <20080909101900.76f843ec@kepler.site> 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-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Bernhard Walle Cc: kexec@lists.infradead.org Bernhard Walle wrote: > * Jay Lan [2008-09-08]: > >> Any input helping me speed up debugging is appreciated. > > I would start with comparing the ELF program headers of /proc/vmcore > which you get with "readelf -l /proc/vmcore" in kdump environment and > the /proc/iomem which kexec uses to set up the ELF core headers. > > If both does contain the memory regions which should not be accessed, > then it's a bug in the ressource assignment of the kernel, and > if /proc/iomem does not, the kexec tool has a bug. Hi Bernhard, I talked to Jack Steiner about this problem. He said: The memory at 0xe000006000100000 is part of Altix "fetchop" space (AKA mspec). The memory supports only uncached attributes. A normal "cached" access may cause MCAs. The kernel should not be using this memory for anything. Only the fetchop driver is suppose to access this area. Note: /proc/iomem shows the memory as "System RAM" but that does NOT mean that is can be accessed w/o special code. See efi.c for the code that prints the iomem info. Maybe efi.c needs to be changed to show a different name for the fetchop memory so that kdump will work. I still need to understand why it did not cause a problem before. Thanks, jay > > > Bernhard > > _______________________________________________ > kexec mailing list > kexec@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec