From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Triplett Subject: Re: [PATCH] Remove warning in efi_enter_virtual_mode Date: Thu, 18 Apr 2013 09:44:58 -0700 Message-ID: <20130418164457.GB6884@leaf> References: <1366127886-31460-1-git-send-email-bryan.odonoghue.lkml@nexus-software.ie> <516EAC4A.6040202@console-pimps.org> <516F1B90.9040508@nexus-software.ie> <516FD24A.3070502@console-pimps.org> <20130418163325.GA6884@leaf> <5170216C.9020300@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <5170216C.9020300@zytor.com> Sender: linux-kernel-owner@vger.kernel.org To: "H. Peter Anvin" Cc: Matt Fleming , Bryan O'Donoghue , matthew.garrett@nebula.com, linux-efi@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, Darren Hart , Ingo Molnar , Thomas Gleixner , Josh Boyer List-Id: linux-efi@vger.kernel.org On Thu, Apr 18, 2013 at 09:38:04AM -0700, H. Peter Anvin wrote: > On 04/18/2013 09:33 AM, Josh Triplett wrote: > > On Thu, Apr 18, 2013 at 12:00:26PM +0100, Matt Fleming wrote: > >>> No, no - we *don't* have a BGRT object at all. > >>> > >>> We have a completely clean memory map - but the BGRT code is causing the > >>> is_ram() failure. > >> > >> You assume that mapping of the Boot Services regions is done purely for > >> the benefit of pulling out the bgrt image - it's not, see the above > >> commit log - and I assumed that you had an ACPI bgrt pointer in your > >> memory map, but you don't. > >> > >> Darren, Josh, have you ever seen an i386 machine with a bgrt pointer? If > >> not, and given that we've never seen an i386 firmware that requires the > >> above workaround from Matthew, combined with the fact that there are so > >> few i386 implementations out there, I'm inclined to apply the patch > >> below, because anything else is a lot more work. We can address this > >> properly if we ever start seeing i386 machines with bgrt pointers that > >> reference highmem. > > > > The machine I developed the BGRT changes on kept the image below the 4G > > mark, inside one of the memory regions reclaimable via > > ExitBootServices(). > > Well, highmem is >= ~896M. Do you have a machine with BGRT over the > highmem mark? I don't have the machine in question anymore, and I don't remember. - Josh Triplett