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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 E34B6C10F0E for ; Mon, 15 Apr 2019 07:03:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3BCD206B7 for ; Mon, 15 Apr 2019 07:03:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726179AbfDOHC7 (ORCPT ); Mon, 15 Apr 2019 03:02:59 -0400 Received: from tyo162.gate.nec.co.jp ([114.179.232.162]:43619 "EHLO tyo162.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725777AbfDOHC7 (ORCPT ); Mon, 15 Apr 2019 03:02:59 -0400 Received: from mailgate02.nec.co.jp ([114.179.233.122]) by tyo162.gate.nec.co.jp (8.15.1/8.15.1) with ESMTPS id x3F72PG3009623 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 15 Apr 2019 16:02:25 +0900 Received: from mailsv01.nec.co.jp (mailgate-v.nec.co.jp [10.204.236.94]) by mailgate02.nec.co.jp (8.15.1/8.15.1) with ESMTP id x3F72Pxr010478; Mon, 15 Apr 2019 16:02:25 +0900 Received: from mail01b.kamome.nec.co.jp (mail01b.kamome.nec.co.jp [10.25.43.2]) by mailsv01.nec.co.jp (8.15.1/8.15.1) with ESMTP id x3F70Msx012625; Mon, 15 Apr 2019 16:02:25 +0900 Received: from bpxc99gp.gisp.nec.co.jp ([10.38.151.135] [10.38.151.135]) by mail03.kamome.nec.co.jp with ESMTP id BT-MMP-4293140; Mon, 15 Apr 2019 16:01:55 +0900 Received: from BPXM12GP.gisp.nec.co.jp ([10.38.151.204]) by BPXC07GP.gisp.nec.co.jp ([10.38.151.135]) with mapi id 14.03.0319.002; Mon, 15 Apr 2019 16:01:54 +0900 From: Junichi Nomura To: Borislav Petkov CC: Dave Young , Chao Fan , Baoquan He , Kairui Song , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel Thread-Topic: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel Thread-Index: AQHU78DnNYRsXw6c0kywKGsyat34OKY1dZqAgACP04CAAAH9AIAABdcAgAAJ5YCAAAJaAIAAAziAgAACJICAADc+AIAA6YwAgABjYACAAE/IgIAESQcA Date: Mon, 15 Apr 2019 07:01:54 +0000 Message-ID: References: <20190411080927.GA30080@zn.tnic> <20190411083738.GC30080@zn.tnic> <2946b5e3-90bf-d617-16a4-d2225b490b5d@ce.jp.nec.com> <20190411125822.GE30080@zn.tnic> <20190412025416.GA11070@jeru.linux.bs1.fc.nec.co.jp> <20190412084956.GC19808@zn.tnic> <20190412133528.GD19808@zn.tnic> In-Reply-To: <20190412133528.GD19808@zn.tnic> Accept-Language: en-US, ja-JP Content-Language: ja-JP X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.34.125.85] Content-Type: text/plain; charset="utf-8" Content-ID: <94E790B68FB193469C00239E878FC0EC@gisp.nec.co.jp> Content-Transfer-Encoding: base64 MIME-Version: 1.0 X-TM-AS-MML: disable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org T24gNC8xMi8xOSAxMDozNSBQTSwgQm9yaXNsYXYgUGV0a292IHdyb3RlOg0KPiBPbiBGcmksIEFw ciAxMiwgMjAxOSBhdCAxMDo0OTo1NkFNICswMjAwLCBCb3Jpc2xhdiBQZXRrb3Ygd3JvdGU6DQo+ PiBOb3cgSSBuZWVkIHRvIGdvIGZpZ3VyZSBvdXQgd2hldGhlciB0aGVyZSdzIGEgcmVsaWFibGUg d2F5IHRvIGtub3cgaW4NCj4+IHRoZSBrZXhlYyBrZXJuZWwgdGhhdCBpdCAqaXMqIGEga2V4ZWMg a2VybmVsLg0KPiANCj4gQWN0dWFsbHksIHRoaW5raW5nIGFib3V0IHRoaXMgbW9yZSwgd2UgZG9u J3QgbmVlZCB0byBrbm93IHdoZXRoZXIgdGhlDQo+IGtlcm5lbCB3YXMga2V4ZWNlZCBvciBub3Qu IFdoeT8NCj4gDQo+IEJlY2F1c2UgaWYgaXQgaXMga2V4ZWMnZWQsIGtleGVjKDEpIHBhc3NlcyB0 aGUgcmVxdWlyZWQgaW5mbyBpbg0KPiBzZXR1cF9kYXRhLiBOb3csIGlmIGZvciB3aGF0ZXZlciBy ZWFzb24gdGhlIGtleGVjJ2VkIGtlcm5lbCBmYWlscyB0bw0KPiBwYXJzZSB0aGF0IEVGSSBpbmZv IGFuZCBnZXQgdGhlIHN5c3RhYiB0byBmaWd1cmUgb3V0IHRoZSBSRFNQLCB0aGVuIGl0DQo+IGRv ZXNuJ3QgaGF2ZSBhbnkgb3RoZXIgY2hvaWNlIGJ1dCBmYWlsIGJvb3RpbmcuDQo+IA0KPiBCZWNh dXNlIHRoZXJlJ3Mgbm8gd2F5IGl0IGNhbiBmaWd1cmUgb3V0IHdoZXJlIHRoZSBFRkkgcnVudGlt ZSBoYXMgYmVlbg0KPiBtYXBwZWQgYW5kIHJlY292ZXIgYnkgZmluZGluZyB0aGUgUkRTUCBmcm9t IHRoZXJlLg0KPiANCj4gU28gSSB0aGluayB3ZSdyZSBwZXJmZWN0bHkgZmluZSB3aXRoIHRoZSBv bGQgYXBwcm9hY2g6DQo+IA0KPiAgICAgICAgIGlmICghcGEpDQo+ICAgICAgICAgICAgICAgICBw YSA9IGtleGVjX2dldF9yc2RwX2FkZHIoKTsNCj4gDQo+ICAgICAgICAgaWYgKCFwYSkNCj4gICAg ICAgICAgICAgICAgIHBhID0gZWZpX2dldF9yc2RwX2FkZHIoKTsNCg0KT0suIFRoZW4gSSdsbCBn byBiYWNrIHRvIHYzIGFuZCBtYWtlIHN1cmUgdG8gaGFuZyB3aGVuDQpzb21ldGhpbmcgaXMgd3Jv bmcgZHVyaW5nIGtleGVjIGJvb3Qgb24gRUZJIHN5c3RlbS4NCg0KLS0gDQpKdW4naWNoaSBOb211 cmEsIE5FQyBDb3Jwb3JhdGlvbiAvIE5FQyBTb2x1dGlvbiBJbm5vdmF0b3JzLCBMdGQu From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from tyo162.gate.nec.co.jp ([114.179.232.162]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hFvdd-0003gD-Fn for kexec@lists.infradead.org; Mon, 15 Apr 2019 07:02:47 +0000 From: Junichi Nomura Subject: Re: [PATCH v4] x86/boot: Use efi_setup_data for searching RSDP on kexec-ed kernel Date: Mon, 15 Apr 2019 07:01:54 +0000 Message-ID: References: <20190411080927.GA30080@zn.tnic> <20190411083738.GC30080@zn.tnic> <2946b5e3-90bf-d617-16a4-d2225b490b5d@ce.jp.nec.com> <20190411125822.GE30080@zn.tnic> <20190412025416.GA11070@jeru.linux.bs1.fc.nec.co.jp> <20190412084956.GC19808@zn.tnic> <20190412133528.GD19808@zn.tnic> In-Reply-To: <20190412133528.GD19808@zn.tnic> Content-Language: ja-JP Content-ID: <94E790B68FB193469C00239E878FC0EC@gisp.nec.co.jp> MIME-Version: 1.0 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: Borislav Petkov Cc: Chao Fan , Kairui Song , Baoquan He , "x86@kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Dave Young On 4/12/19 10:35 PM, Borislav Petkov wrote: > On Fri, Apr 12, 2019 at 10:49:56AM +0200, Borislav Petkov wrote: >> Now I need to go figure out whether there's a reliable way to know in >> the kexec kernel that it *is* a kexec kernel. > > Actually, thinking about this more, we don't need to know whether the > kernel was kexeced or not. Why? > > Because if it is kexec'ed, kexec(1) passes the required info in > setup_data. Now, if for whatever reason the kexec'ed kernel fails to > parse that EFI info and get the systab to figure out the RDSP, then it > doesn't have any other choice but fail booting. > > Because there's no way it can figure out where the EFI runtime has been > mapped and recover by finding the RDSP from there. > > So I think we're perfectly fine with the old approach: > > if (!pa) > pa = kexec_get_rsdp_addr(); > > if (!pa) > pa = efi_get_rsdp_addr(); OK. Then I'll go back to v3 and make sure to hang when something is wrong during kexec boot on EFI system. -- Jun'ichi Nomura, NEC Corporation / NEC Solution Innovators, Ltd. _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec