From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Xopo4-0004MO-E6 for kexec@lists.infradead.org; Thu, 13 Nov 2014 08:31:09 +0000 Received: from kw-mxq.gw.nic.fujitsu.com (unknown [10.0.237.131]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id D5BF93EE0C2 for ; Thu, 13 Nov 2014 17:30:43 +0900 (JST) Received: from s1.gw.fujitsu.co.jp (s1.gw.fujitsu.co.jp [10.0.50.91]) by kw-mxq.gw.nic.fujitsu.com (Postfix) with ESMTP id E744BAC0803 for ; Thu, 13 Nov 2014 17:30:42 +0900 (JST) Received: from m3051.s.css.fujitsu.com (m3051.s.css.fujitsu.com [10.134.21.209]) by s1.gw.fujitsu.co.jp (Postfix) with ESMTP id 8E9A71DB8042 for ; Thu, 13 Nov 2014 17:30:42 +0900 (JST) Message-ID: <54646C1D.1050102@jp.fujitsu.com> Date: Thu, 13 Nov 2014 17:30:21 +0900 From: "HATAYAMA, Daisuke" MIME-Version: 1.0 Subject: Re: [PATCH] kdump, x86: report actual value of phys_base in VMCOREINFO References: <20141112.154042.59640143160036130.d.hatayama@jp.fujitsu.com> <20141112221205.GB5265@redhat.com> <20141113.091709.520211949477822929.d.hatayama@jp.fujitsu.com> <20141113090657.2578f087@hananiah.suse.cz> In-Reply-To: <20141113090657.2578f087@hananiah.suse.cz> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Petr Tesarik Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org, anderson@redhat.com, ebiederm@xmission.com, kumagai-atsushi@mxc.nes.nec.co.jp, vgoyal@redhat.com (2014/11/13 17:06), Petr Tesarik wrote: > On Thu, 13 Nov 2014 09:17:09 +0900 (JST) > HATAYAMA Daisuke wrote: > >> From: Vivek Goyal >> Subject: Re: [PATCH] kdump, x86: report actual value of phys_base in VMCOREINFO >> Date: Wed, 12 Nov 2014 17:12:05 -0500 >> >>> On Wed, Nov 12, 2014 at 03:40:42PM +0900, HATAYAMA Daisuke wrote: >>>> Currently, VMCOREINFO note information reports the virtual address of >>>> phys_base that is assigned to symbol phys_base. But this doesn't make >>>> sense because to refer to value of the phys_base, it's necessary to >>>> get the value of phys_base itself we are now about to refer to. >>>> >>> >>> Hi Hatayama, >>> >>> /proc/vmcore ELF headers have virtual address information and using >>> that you should be able to read actual value of phys_base. gdb deals >>> with virtual addresses all the time and can read value of any symbol >>> using those headers. >>> >>> So I am not sure what's the need for exporting actual value of >>> phys_base. >>> >> >> Sorry, my logic in the patch description was wrong. For /proc/vmcore, >> there's enough information for makedumpdile to get phys_base. It's >> correct. The problem here is that other crash dump mechanisms that run >> outside Linux kernel independently don't have information to get >> phys_base. > > Yes, but these mechanisms won't be able to read VMCOREINFO either, will > they? > I don't intend such sophisticated function only by VMCOREINFO. Search vmcore for VMCOREINFO using strings + grep before opening it by crash. I intend that only here. -- Thanks. HATAYAMA, Daisuke _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec