From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH -v2 0/4] EFI 1:1 mapping Date: Wed, 19 Jun 2013 18:59:02 +0200 Message-ID: <20130619165902.GH28300@pd.tnic> References: <1371491416-11037-1-git-send-email-bp@alien8.de> <20130619125243.GD11209@gmail.com> <20130619130225.GA28311@pd.tnic> <20130619130434.GB24957@gmail.com> <20130619160804.GB27832@srcf.ucam.org> <20130619161827.GF28300@pd.tnic> <20130619162115.GA28119@srcf.ucam.org> <20130619163804.GG28300@pd.tnic> <20130619164822.GA28240@srcf.ucam.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <20130619164822.GA28240-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Matthew Garrett Cc: Ingo Molnar , Linux EFI , Matt Fleming , X86 ML , LKML , Borislav Petkov , "H. Peter Anvin" List-Id: linux-efi@vger.kernel.org On Wed, Jun 19, 2013 at 05:48:22PM +0100, Matthew Garrett wrote: > > Ok, so it sounds like we want to *always* create both mappings but, > > depending on what we want, to shove down SetVirtualAddressMap a > > different set. And the 1:1 map will be the optional one which we give > > SetVirtualAddressMap only when user wants it, i.e. when booting with > > "efi=1:1_map". > > Yup, I think that sounds ideal. Crap, I got completely sidetracked. The 1:1 mappings go in a different pagetable (real_mode_header->trampoline_pgd) than the kernel one (i.e. init_mm.pgd). However, the ->trampoline_pgd has all mappings anyway, which means that if we want to do EFI runtime calls with the high mappings but *also* have the 1:1 mappings established, we should *always* switch to that pagetable when doing those calls. hpa, MattF, agreed? -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --