From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032683AbdDTOYp (ORCPT ); Thu, 20 Apr 2017 10:24:45 -0400 Received: from mx2.suse.de ([195.135.220.15]:34915 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1032669AbdDTOYo (ORCPT ); Thu, 20 Apr 2017 10:24:44 -0400 Subject: Re: [PATCH v4 1/3] kexec: Move vmcoreinfo out of the kernel's .bss section To: Xunlei Pang , linux-kernel@vger.kernel.org, kexec@lists.infradead.org References: <1492688374-27903-1-git-send-email-xlpang@redhat.com> Cc: akpm@linux-foundation.org, Eric Biederman , Dave Young , Baoquan He , Petr Tesarik , Hari Bathini , Michael Holzheu From: Juergen Gross Message-ID: <325a8a1b-8f52-b05d-3b7f-440f365dfbbc@suse.com> Date: Thu, 20 Apr 2017 16:24:41 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <1492688374-27903-1-git-send-email-xlpang@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 20/04/17 13:39, Xunlei Pang wrote: > As Eric said, > "what we need to do is move the variable vmcoreinfo_note out > of the kernel's .bss section. And modify the code to regenerate > and keep this information in something like the control page. > > Definitely something like this needs a page all to itself, and ideally > far away from any other kernel data structures. I clearly was not > watching closely the data someone decided to keep this silly thing > in the kernel's .bss section." > > This patch allocates extra pages for these vmcoreinfo_XXX variables, > one advantage is that it enhances some safety of vmcoreinfo, because > vmcoreinfo now is kept far away from other kernel data structures. > > Suggested-by: Eric Biederman > Cc: Michael Holzheu > Cc: Juergen Gross > Signed-off-by: Xunlei Pang Xen parts: Reviewed-by: Juergen Gross Juergen