From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755504Ab3KLS7O (ORCPT ); Tue, 12 Nov 2013 13:59:14 -0500 Received: from terminus.zytor.com ([198.137.202.10]:37267 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752644Ab3KLS7N (ORCPT ); Tue, 12 Nov 2013 13:59:13 -0500 User-Agent: K-9 Mail for Android In-Reply-To: <1384222558-38527-1-git-send-email-jerry.hoemann@hp.com> References: <1384222558-38527-1-git-send-email-jerry.hoemann@hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: Re: [PATCH 0/3] Early use of boot service memory From: "H. Peter Anvin" Date: Tue, 12 Nov 2013 10:58:42 -0800 To: Jerry Hoemann , rob@landley.net, tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, matt.fleming@intel.com, yinghai@kernel.org, penberg@kernel.org, akpm@linux-foundation.org, linux-doc@vger.kernel.org, linux-efi@vger.kernel.org, vgoyal@redhat.com CC: linux-kernel@vger.kernel.org Message-ID: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The problem with the crashkernel is that it by default has to sit very low in memory because the tools don't know if the crashkernel is me enough to sit anywhere. That is the real fix. Jerry Hoemann wrote: >Some platform have firmware that violates UEFI spec and access boot >service >code or data segments after the system has called Exit Boot Services. >The call to efi_reserve_boot_services in setup_arch is a work around to >avoid using boot service memory until after the kernel has done >Set Virtual Map. > >However, this reservation fragments memory which can cause >large allocations early in boot (e.g. crash kernel) to fail. > >This patch set extends the add_efi_memmap with an optional >argument to specify that firmware "correctly" doesn't resuse >boot services memory after Exit Boot Services. > >With this information, setup_arch avoids calling >efi_reserve_boot_services and fragmenting memory. > > >Jerry Hoemann (3): > efi: Early use of boot service memory > x86: avoid efi_reserve_boot_services > x86, efi: Early use of boot service memory > > Documentation/kernel-parameters.txt | 8 ++++++++ > arch/x86/kernel/setup.c | 2 +- > arch/x86/platform/efi/efi.c | 13 +++++++++++-- > include/linux/efi.h | 1 + > 4 files changed, 21 insertions(+), 3 deletions(-) -- Sent from my mobile phone. Please pardon brevity and lack of formatting.