From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail.skyhub.de ([2a01:4f8:190:11c2::b:1457]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1gn29r-0007xB-Nz for kexec@lists.infradead.org; Fri, 25 Jan 2019 14:08:38 +0000 Date: Fri, 25 Jan 2019 15:08:23 +0100 From: Borislav Petkov Subject: Re: [PATCHv7] x86/kdump: bugfix, make the behavior of crashkernel=X consistent with kaslr Message-ID: <20190125140823.GC27998@zn.tnic> References: <1548047768-7656-1-git-send-email-kernelfans@gmail.com> <20190125103924.GB27998@zn.tnic> <20190125134518.GA23595@dhcp-128-65.nay.redhat.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190125134518.GA23595@dhcp-128-65.nay.redhat.com> 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=infradead.org@lists.infradead.org To: Dave Young Cc: x86@kernel.org, Baoquan He , Randy Dunlap , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Pingfan Liu , Mike Rapoport , Andrew Morton , yinghai@kernel.org, vgoyal@redhat.com On Fri, Jan 25, 2019 at 09:45:18PM +0800, Dave Young wrote: > AFAIK, some people prefer to explictly reserve crash memory at high > region even if it is possible to reserve at low area. May because > <4G memory is limited on large server, they want to leave this for other > use. > > Yinghai or Vivek should know more about the history, probably they can > recall some initial reason. Yes, just "prefer" is not good enough. There should be a technical reason why that's there. Also, if the user doesn't care, then the code should be free to force "high" and thus probe a different range for allocation. > Good question, still it may be some historical reason, but it is good to > make them clear and rethink about it after long time. > > I also want to understand, need dig the log more. Good idea. That would be a very nice cleanup. :-) Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CAC45C282C0 for ; Fri, 25 Jan 2019 14:08:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 91119218CD for ; Fri, 25 Jan 2019 14:08:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="TcPE359E" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728641AbfAYOIb (ORCPT ); Fri, 25 Jan 2019 09:08:31 -0500 Received: from mail.skyhub.de ([5.9.137.197]:49918 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726095AbfAYOIb (ORCPT ); Fri, 25 Jan 2019 09:08:31 -0500 Received: from zn.tnic (p200300EC2BCAC50014C06278D1E5EF9B.dip0.t-ipconnect.de [IPv6:2003:ec:2bca:c500:14c0:6278:d1e5:ef9b]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id 5A76E1EC035B; Fri, 25 Jan 2019 15:08:29 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1548425309; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=8t47gKa0bxXB/mNvnju+bpEatbuBCy638ZZbK87SBws=; b=TcPE359Es2imxEu42hbAxo9QiKW2JLfNDWTVSdCBQchZl98CbN/HYTTLyETwMUcxWCq0JX z0tooeCu18vPZXgmeyidZjYgmeXB1/nHl3Tnaf+EDh/Cb+J0qXMvaGGtEfdEX4/J8byg3Z MEnLsWU98GMWQUnKRWlBmUkFy1ROvzM= Date: Fri, 25 Jan 2019 15:08:23 +0100 From: Borislav Petkov To: Dave Young Cc: Pingfan Liu , kexec@lists.infradead.org, Baoquan He , Andrew Morton , Mike Rapoport , yinghai@kernel.org, vgoyal@redhat.com, Randy Dunlap , x86@kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCHv7] x86/kdump: bugfix, make the behavior of crashkernel=X consistent with kaslr Message-ID: <20190125140823.GC27998@zn.tnic> References: <1548047768-7656-1-git-send-email-kernelfans@gmail.com> <20190125103924.GB27998@zn.tnic> <20190125134518.GA23595@dhcp-128-65.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20190125134518.GA23595@dhcp-128-65.nay.redhat.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 25, 2019 at 09:45:18PM +0800, Dave Young wrote: > AFAIK, some people prefer to explictly reserve crash memory at high > region even if it is possible to reserve at low area. May because > <4G memory is limited on large server, they want to leave this for other > use. > > Yinghai or Vivek should know more about the history, probably they can > recall some initial reason. Yes, just "prefer" is not good enough. There should be a technical reason why that's there. Also, if the user doesn't care, then the code should be free to force "high" and thus probe a different range for allocation. > Good question, still it may be some historical reason, but it is good to > make them clear and rethink about it after long time. > > I also want to understand, need dig the log more. Good idea. That would be a very nice cleanup. :-) Thx. -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.