From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Young Subject: Re: [PATCH v2 14/16] x86, nvdimm, kexec: Use walk_iomem_res_desc() for iomem search Date: Mon, 4 Jan 2016 17:29:37 +0800 Message-ID: <20160104092937.GB7033@dhcp-128-65.nay.redhat.com> References: <1451081365-15190-1-git-send-email-toshi.kani@hpe.com> <1451081365-15190-14-git-send-email-toshi.kani@hpe.com> <20151226103804.GB21988@pd.tnic> <567F315B.8080005@hpe.com> <20151227021257.GA13560@dhcp-128-25.nay.redhat.com> <20151227102406.GB19398@nazgul.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mx1.redhat.com ([209.132.183.28]:52252 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752658AbcADJ3x (ORCPT ); Mon, 4 Jan 2016 04:29:53 -0500 Content-Disposition: inline In-Reply-To: <20151227102406.GB19398@nazgul.tnic> Sender: linux-arch-owner@vger.kernel.org List-ID: To: Borislav Petkov Cc: Minfei Huang , Toshi Kani , linux-arch@vger.kernel.org, linux-nvdimm@ml01.01.org, x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, Dan Williams Hi, Boris On 12/27/15 at 11:24am, Borislav Petkov wrote: > On Sun, Dec 27, 2015 at 10:12:57AM +0800, Minfei Huang wrote: > > You can refer the below link that you may get a clue about GART. This is > > the fisrt time kexec-tools tried to support to ignore GART region in 2nd > > kernel. > > > > http://lists.infradead.org/pipermail/kexec/2008-December/003096.html > > So theoretically we could export that IORES_DESC* enum in an uapi header and > move kexec-tools to use that. > > However, I'm fuzzy on how exactly the whole compatibility thing is done > with kexec-tools and the kernel. We probably would have to support > newer kexec-tools on an older kernel and vice versa so I'd guess we > should mark walk_iomem_res() deprecated so that people are encouraged to > upgrade to newer kexec-tools... Replied to Toshi old kernel will export the "GART" region for amd cards. So for old kernel and new kexec-tools we will have problem. I think add the GART desc for compitibility purpose is doable, no? Thanks Dave