From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH 4/4] x86, efi: Map runtime services 1:1 Date: Thu, 6 Jun 2013 21:36:13 +0200 Message-ID: <20130606193612.GM20972@pd.tnic> References: <1370177770-26661-1-git-send-email-bp@alien8.de> <1370177770-26661-5-git-send-email-bp@alien8.de> <20130606131439.GI30420@console-pimps.org> <20130606132908.GE20972@pd.tnic> <20130606155822.GH20972@pd.tnic> <51B0E2D4.3040007@zytor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <51B0E2D4.3040007-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "H. Peter Anvin" Cc: Matt Fleming , Linux EFI , Matthew Garrett , Jiri Kosina , X86-ML , LKML , Borislav Petkov List-Id: linux-efi@vger.kernel.org On Thu, Jun 06, 2013 at 12:28:20PM -0700, H. Peter Anvin wrote: > Or we could materialize mappings for this specific PGD. However, > adding a read of %cr3 in __do_page_fault sounds expensive. Yes, I think we want to make sure all mappings are there when we do an EFI runtime call so that we never #PF while it executes. Matt mentioned on IRC that the it could be that his EFI runtime is referencing EFI_RESERVED area which we don't map. However, we need to confirm/disprove that first, as it is currently only a hunch. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --