Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752997AbcCAV5A (ORCPT ); Tue, 1 Mar 2016 16:57:00 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:41816 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751349AbcCAV47 (ORCPT ); Tue, 1 Mar 2016 16:56:59 -0500 Date: Tue, 1 Mar 2016 13:56:58 -0800 From: Andrew Morton To: Minfei Huang Cc: ebiederm@xmission.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, mhuang@redhat.com Subject: Re: [PATCH V2 1/2] kexec: Make a pair of map/unmap reserved pages in error path Message-Id: <20160301135658.341928989a18949d97998abd@linux-foundation.org> In-Reply-To: <1456819349-8650-2-git-send-email-mnfhuang@gmail.com> References: <1456819349-8650-1-git-send-email-mnfhuang@gmail.com> <1456819349-8650-2-git-send-email-mnfhuang@gmail.com> X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 558 Lines: 15 On Tue, 1 Mar 2016 16:02:28 +0800 Minfei Huang wrote: > For some arch, kexec shall map the reserved pages, then use them, when > we try to start the kdump service. Which architectures are these, by the way? > kexec may return directly, without unmaping the reserved pages, if it > fails during starting service. To fix it, we make a pair of map/unmap > reserved pages both in generic path and error path. I'm having trouble understanding the urgency of this patch. Do you think it is needed in 4.5? -stable? If so, why? Thanks.