From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754131AbaHGHHy (ORCPT ); Thu, 7 Aug 2014 03:07:54 -0400 Received: from mail-wi0-f175.google.com ([209.85.212.175]:51650 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752936AbaHGHHx convert rfc822-to-8bit (ORCPT ); Thu, 7 Aug 2014 03:07:53 -0400 References: <20140806083825.GA31711@dhcp-16-198.nay.redhat.com> <20140807012847.GB20295@darkstar.nay.redhat.com> Mime-Version: 1.0 (1.0) In-Reply-To: <20140807012847.GB20295@darkstar.nay.redhat.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Message-Id: <7F205346-C978-4FC1-8812-2A37AFA06312@linaro.org> Cc: Catalin Marinas , Will Deacon , Matt Fleming , Leif Lindholm , Mark Salter , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" X-Mailer: iPad Mail (11D257) From: Ard Biesheuvel Subject: Re: [PATCH 1/2] UEFI arm64: add noefi boot param Date: Thu, 7 Aug 2014 09:07:51 +0200 To: Dave Young Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On 7 aug. 2014, at 03:28, Dave Young wrote: > >> On 08/06/14 at 02:40pm, Ard Biesheuvel wrote: >>> On 6 August 2014 10:38, Dave Young wrote: >>> >>> Adding a noefi boot param like in X86 to disable efi runtime services support. >>> >>> This will be useful for debugging uefi problems. Also it will be useful >>> for later kexec/kdump work. Kexec on uefi support in X86 depends on a fixed vm >>> area specific for uefi runtime 1:1 mapping, kernel will switch to a different >>> page table for any uefi runtime callback in virtual mode. In arm64 similar >>> work probably is necessary. But kexec boot will just works with 'noefi' with >>> the limitaion of lacking runtime services. The runtime services is not critical >>> for kdump kernel for now. So as for kexec/kdump just leave the 1:1 mapping a >>> future work. >> >> Can we find a better name? You will still be using the UEFI memory map >> rather than the DT memory nodes (which will have been deleted by the >> stub), and things like SMBIOS and ACPI that hinge off UEFI remain >> enabled as well. > Hi, Ard > > Leif suggested efi=noruntime, I think that will be better to you? > Yes, that sounds perfect to me Ard. > Thanks for review. > Dave