From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx166.postini.com [74.125.245.166]) by kanga.kvack.org (Postfix) with SMTP id 07DED6B005D for ; Wed, 3 Oct 2012 01:36:00 -0400 (EDT) Message-ID: <506BCEAB.4090204@zytor.com> Date: Tue, 02 Oct 2012 22:35:39 -0700 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: [PATCH] Fix devmem_is_allowed for below 1MB accesses for an efi machine References: <1349213536-3436-1-git-send-email-tmac@hp.com> <506B6191.6080605@zytor.com> <20121003043116.GA26241@srcf.ucam.org> <506BC2A0.8060500@zytor.com> <20121003051522.GA27113@srcf.ucam.org> <506BC96D.10507@hp.com> <20121003052803.GA27464@srcf.ucam.org> In-Reply-To: <20121003052803.GA27464@srcf.ucam.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Matthew Garrett Cc: Thavatchai Makphaibulchoke , T Makphaibulchoke , tglx@linutronix.de, mingo@redhat.com, x86@kernel.org, akpm@linux-foundation.org, yinghai@kernel.org, tiwai@suse.de, viro@zeniv.linux.org.uk, aarcange@redhat.com, tony.luck@intel.com, mgorman@suse.de, weiyang@linux.vnet.ibm.com, octavian.purdila@intel.com, paul.gortmaker@windriver.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org On 10/02/2012 10:28 PM, Matthew Garrett wrote: > On Tue, Oct 02, 2012 at 11:13:17PM -0600, Thavatchai Makphaibulchoke wrote: > >> Sounds like a better solution is to allow accesses to only I/O regions >> presented in the EFI memory map for physical addresses below 1 MB. > > That won't work - unfortunately we do still need the low region to be > available for X because some platforms expect us to use int10 even on > EFI (yes, yes, I know). Do you have a copy of the EFI memory map for a > system that's broken with the current code? > I honestly think this calls for a quirk, or more likely, no action at all ("don't do that, then.") -hpa -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org