From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752773AbaHFN3x (ORCPT ); Wed, 6 Aug 2014 09:29:53 -0400 Received: from mail-we0-f169.google.com ([74.125.82.169]:47130 "EHLO mail-we0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730AbaHFN3u (ORCPT ); Wed, 6 Aug 2014 09:29:50 -0400 Date: Wed, 6 Aug 2014 14:29:41 +0100 From: Leif Lindholm To: Matt Fleming Cc: Dave Young , catalin.marinas@arm.com, will.deacon@arm.com, matt.fleming@intel.com, ard.biesheuvel@linaro.org, msalter@redhat.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org Subject: Re: [PATCH 1/2] UEFI arm64: add noefi boot param Message-ID: <20140806132941.GJ4179@bivouac.eciton.net> References: <20140806083825.GA31711@dhcp-16-198.nay.redhat.com> <20140806130623.GI4179@bivouac.eciton.net> <20140806132021.GB15082@console-pimps.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20140806132021.GB15082@console-pimps.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 06, 2014 at 02:20:21PM +0100, Matt Fleming wrote: > > Since this is really turning an x86-specific feature into a generic > > one, could it be moved to core code? > > Maybe an efi.mask, reusing the efi_enabled defines, with an > > efi_disabled macro? > > Why the new efi_disabled() and efi.mask? This is all achievable with > efi_enabled() and efi.flags, in fact, this kind of thing is exactly why > they were invented. Because this flag is indicating which facilities we should not try to enable, rather than which facilities we have enabled. The EFI_RUNTIME_SERVICES flag is set after successful call to set_virtual_address_map. The apparent intent of "noefi" is to prevent that call from being made in the first place. Anyway, it was just a suggestion - main point was it would make sense to share the code. > > Also, since this patch (and its x86 predecessor) is not really > > "noefi", could this be integrated with the "efi=" patch > > (http://permalink.gmane.org/gmane.linux.kernel.efi/4405), > > as an efi=noruntime option? > > > > On x86, due to CSM, "noefi" was a useful fallback for completely > > broken (U)EFI implementations - but on an arm* UEFI system, there will > > be no fallback. Could it be wrapped in a kernel hacking config option? > > I don't mind making "noefi" a synonym for "efi=noruntime" on x86, as > long as we keep "noefi" around with the same semantics it's always had. Yeah, that would be nice. / Leif