From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933399Ab3GPPzq (ORCPT ); Tue, 16 Jul 2013 11:55:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:1406 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933360Ab3GPPzb (ORCPT ); Tue, 16 Jul 2013 11:55:31 -0400 Date: Tue, 16 Jul 2013 11:55:00 -0400 From: Vivek Goyal To: Michael Holzheu Cc: HATAYAMA Daisuke , Andrew Morton , Jan Willeke , Martin Schwidefsky , Heiko Carstens , linux-kernel@vger.kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH v6 3/5] vmcore: Introduce remap_oldmem_pfn_range() Message-ID: <20130716155459.GB3398@redhat.com> References: <1372707159-10425-1-git-send-email-holzheu@linux.vnet.ibm.com> <1372707159-10425-4-git-send-email-holzheu@linux.vnet.ibm.com> <20130702154214.GC22603@redhat.com> <20130715154451.02a3a767@holzheu> <20130715142708.GB23772@redhat.com> <20130716112527.35decf17@holzheu> <20130716140418.GB4005@redhat.com> <20130716173709.3fed4c42@holzheu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130716173709.3fed4c42@holzheu> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 16, 2013 at 05:37:09PM +0200, Michael Holzheu wrote: [..] > The problem is that with the mmap patches we now use copy_oldmem_page() > to copy the notes from oldmem into the notes_buf which has been allocated > with vmalloc. The s390 version of copy_oldmem_page() bypasses the page > tables and uses real copy. And this does not work on vmalloc memory. I got that. I am trying to remember that in 3.10 why are we dropping to real mode in s390 while copying pages. I thought dropping to real mode was needed only to access HSA region. HSA region comes into the picture only for zfcudump and /proc/vmcore support for zfcpdump is not there yet IOW, what if we start copying with page tables enabled in s390. Will it not work for regular kdump case and take care of zfcpdump in 3.12. Thanks Vivek From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Uz7b7-0000Dz-Lh for kexec@lists.infradead.org; Tue, 16 Jul 2013 15:55:30 +0000 Date: Tue, 16 Jul 2013 11:55:00 -0400 From: Vivek Goyal Subject: Re: [PATCH v6 3/5] vmcore: Introduce remap_oldmem_pfn_range() Message-ID: <20130716155459.GB3398@redhat.com> References: <1372707159-10425-1-git-send-email-holzheu@linux.vnet.ibm.com> <1372707159-10425-4-git-send-email-holzheu@linux.vnet.ibm.com> <20130702154214.GC22603@redhat.com> <20130715154451.02a3a767@holzheu> <20130715142708.GB23772@redhat.com> <20130716112527.35decf17@holzheu> <20130716140418.GB4005@redhat.com> <20130716173709.3fed4c42@holzheu> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20130716173709.3fed4c42@holzheu> 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=twosheds.infradead.org@lists.infradead.org To: Michael Holzheu Cc: kexec@lists.infradead.org, Heiko Carstens , linux-kernel@vger.kernel.org, Jan Willeke , HATAYAMA Daisuke , Martin Schwidefsky , Andrew Morton On Tue, Jul 16, 2013 at 05:37:09PM +0200, Michael Holzheu wrote: [..] > The problem is that with the mmap patches we now use copy_oldmem_page() > to copy the notes from oldmem into the notes_buf which has been allocated > with vmalloc. The s390 version of copy_oldmem_page() bypasses the page > tables and uses real copy. And this does not work on vmalloc memory. I got that. I am trying to remember that in 3.10 why are we dropping to real mode in s390 while copying pages. I thought dropping to real mode was needed only to access HSA region. HSA region comes into the picture only for zfcudump and /proc/vmcore support for zfcpdump is not there yet IOW, what if we start copying with page tables enabled in s390. Will it not work for regular kdump case and take care of zfcpdump in 3.12. Thanks Vivek _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec