From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from g6t0184.atlanta.hp.com ([15.193.32.61]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VOkrz-000102-Of for kexec@lists.infradead.org; Wed, 25 Sep 2013 08:54:53 +0000 Message-ID: <5242A4BF.5090903@hp.com> Date: Wed, 25 Sep 2013 16:54:23 +0800 From: Jingbai Ma MIME-Version: 1.0 Subject: Re: [PATCH] makedumpfile: fix max_mapnr issue on system has over 44-bit addressing References: <20130924124931.14715.24507.stgit@k.asiapacific.hpqcorp.net> <52422FCF.1030206@jp.fujitsu.com> <52429BF1.3050303@hp.com> <5242A13B.6000907@jp.fujitsu.com> In-Reply-To: <5242A13B.6000907@jp.fujitsu.com> 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=twosheds.infradead.org@lists.infradead.org To: HATAYAMA Daisuke Cc: bhe@redhat.com, nishimura@mxp.nes.nec.co.jp, usui@mxm.nes.nec.co.jp, chaowang@redhat.com, lisa.mitchell@hp.com, ruyang@redhat.com, tachibana@mxm.nes.nec.co.jp, anderson@redhat.com, vgoyal@redhat.com, kumagai-atsushi@mxc.nes.nec.co.jp, kexec@lists.infradead.org, Jingbai Ma , crash-utility@redhat.com On 09/25/2013 04:39 PM, HATAYAMA Daisuke wrote: > (2013/09/25 17:16), Jingbai Ma wrote: > >>> >>>> @@ -5153,10 +5160,11 @@ write_kdump_header(void) >>>> * Write common header >>>> */ >>>> strncpy(dh->signature, KDUMP_SIGNATURE, strlen(KDUMP_SIGNATURE)); >>>> - dh->header_version = 5; >>>> + dh->header_version = 6; >>>> dh->block_size = info->page_size; >>>> dh->sub_hdr_size = sizeof(kh) + size_note; >>>> dh->sub_hdr_size = divideup(dh->sub_hdr_size, dh->block_size); >>>> + /* dh->max_mapnr may be truncated here, full 64bit in kh.max_mapnr */ >>>> dh->max_mapnr = info->max_mapnr; >>> >>> dh->max_mapnr = MIN(info->max_mapnr, UINT_MAX) seems better for old >>> versions of crash utitlity. >>> >> >> Although change this value to UINT_MAX doesn't help the old crash >> utility very much. At least this special value will tell the user >> something happened. >> Will fix it. >> >> > > This is the largest page frame number old crash utilities can represent, > not special value. > By this, old crash utilities can read at least the pages less than > UINT_MAX, > which is better than making dh->max_mapnr overflow; then dh->max_mapnr > would typically become > a small number. > I knew, but crash utility may still report reading page error before its command prompt. Anyway, UINT_MAX has a better chance to make old utility happy, so I will fix it. :) -- Thanks, Jingbai Ma _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec