From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934173AbcHJTHJ (ORCPT ); Wed, 10 Aug 2016 15:07:09 -0400 Received: from mail-wm0-f67.google.com ([74.125.82.67]:36400 "EHLO mail-wm0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934190AbcHJTHG (ORCPT ); Wed, 10 Aug 2016 15:07:06 -0400 Date: Wed, 10 Aug 2016 14:30:58 +0200 From: Ingo Molnar To: Andy Lutomirski Cc: "H. Peter Anvin" , x86@kernel.org, Mario Limonciello , Matthew Garrett , Borislav Petkov , Matt Fleming , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 0/5] Allow the trampoline to use EFI boot services RAM Message-ID: <20160810123058.GB3204@gmail.com> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org One side note: * Andy Lutomirski wrote: > This series fixes it the other way: it allow the trampoline to live > in boot services memory. It achieves this by deferring the panic > due to failure to reserve a trampoline until early_initcall time > and then adjusting the EFI boot services quirk to reserve space > for the trampoline if we haven't already found it a home. > x86/efi: Allocate a trampoline if needed in efi_free_boot_services() Btw., this means that we first try to allocate the trampoline the old fashioned way, and in the rare cases this fails we allocate it from the EFI data area, right? This is problematic from the probability management POV: we are creating a rare piece of code that will run only on a select few systems. I think it would be much better to allocate the trampoline from the EFI area on all EFI systems by default. Is there any reason why that would not work? Thanks, Ingo