From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752963AbdARNds (ORCPT ); Wed, 18 Jan 2017 08:33:48 -0500 Received: from mx1.redhat.com ([209.132.183.28]:38692 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752095AbdARNdq (ORCPT ); Wed, 18 Jan 2017 08:33:46 -0500 Date: Wed, 18 Jan 2017 21:33:32 +0800 From: Dave Young To: Nicolai Stange Cc: Ard Biesheuvel , Matt Fleming , "linux-efi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "x86@kernel.org" , Ingo Molnar , Thomas Gleixner , "hpa@zytor.com" , Dan Williams , Mika =?iso-8859-1?Q?Penttil=E4?= , Bhupesh Sharma Subject: Re: [PATCH V2 4/4] efi/x86: make efi_memmap_reserve only insert into boot mem areas Message-ID: <20170118133332.GA10481@dhcp-128-65.nay.redhat.com> References: <20170116024554.461236678@redhat.com> <20170116025026.586405871@redhat.com> <871sw131t7.fsf@gmail.com> <20170118110105.GA7377@dhcp-128-65.nay.redhat.com> <20170118110612.GA7487@dhcp-128-65.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170118110612.GA7487@dhcp-128-65.nay.redhat.com> User-Agent: Mutt/1.7.1 (2016-10-04) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 18 Jan 2017 13:33:46 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/18/17 at 07:06pm, Dave Young wrote: > On 01/18/17 at 07:01pm, Dave Young wrote: > > On 01/17/17 at 08:48pm, Nicolai Stange wrote: > > > On Tue, Jan 17 2017, Ard Biesheuvel wrote: > > > > > > > On 16 January 2017 at 02:45, Dave Young wrote: > > > >> efi_mem_reserve cares only about boot services regions, for making sure > > > >> later efi_free_boot_services does not free areas which are still useful, > > > >> such as bgrt image buffer. > > > >> > > > >> So add a new argument to efi_memmap_insert for this purpose. > > > >> > > > > > > > > So what happens is we try to efi_mem_reserve() a regions that is not > > > > bootservices code or data? > > > > We shouldn't simply ignore it, because it is a serious condition. > > > > > > The efi_mem_desc_lookup() call in efi_arch_mem_reserve() wouldn't return > > > anything and the latter would > > > > > > pr_err("Failed to lookup EFI memory descriptor for %pa\n", &addr); > > > > > > then. > > > > > > This is so because efi_mem_desc_lookup() searches only for regions that > > > either > > > - are of type EFI_BOOT_SERVICES_DATA or EFI_RUNTIME_SERVICES_DATA > > > - or which have EFI_MEMORY_RUNTIME set already: > > > > > > if (!(md->attribute & EFI_MEMORY_RUNTIME) && > > > md->type != EFI_BOOT_SERVICES_DATA && > > > md->type != EFI_RUNTIME_SERVICES_DATA) { > > > continue; > > > } > > > > > > For EFI_RUNTIME_SERVICES_DATA and EFI_MEMORY_RUNTIME, > > > efi_arch_mem_reserve() would be a nop. > > > > > > So we're fine here? Do you want to have a more descriptive error message > > > than "Failed to lookup EFI memory descriptor"? > > > > > > > > > For the other checks you suggested in that other thread, i.e. for the > > > post-slab_is_available() condition and so: let me wait until Dave's > > > series has stabilized (or even picked) and I'll submit patches for > > > what remains to be sanity checked then. > > > > > > Also, since Dave eliminated the need for late efi_mem_reserve()'s, > > > my 20b1e22d01a4 ("x86/efi: Don't allocate memmap through memblock after > > > mm_init()") should certainly get reverted at some point. > > > > While testing my patches with latest edk2, I found another thing to be > > fixed, I will repost bgrt patch according to Ard's comment tomorrow, > > maybe with below patch as another fix to the memblock_alloc late > > callback. Please ignore the comment, your patch already addressed this, that means it is still necessary after bgrt being moved early because efi_free_boot_services still need it. Apologize for the noise.. > > > > --- > > arch/x86/platform/efi/quirks.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > --- linux-x86.orig/arch/x86/platform/efi/quirks.c > > +++ linux-x86/arch/x86/platform/efi/quirks.c > > @@ -355,7 +355,7 @@ void __init efi_free_boot_services(void) > > } > > > > new_size = efi.memmap.desc_size * num_entries; > > - new_phys = kzalloc(new_size, GFP_KERNEL); > > Oops, it was memblock_alloc(), this is a middle test code used for > debugging. Just ignore it. > > > + new_phys = efi_memmap_alloc(num_entries); > > Maybe a efi_memmap_late_alloc is enough, will see if I can get a better > version, maybe your previous patch can be dropped partially or just > kept. > > > if (!new_phys) { > > pr_err("Failed to allocate new EFI memmap\n"); > > return; > > > > > > > > > > > Thanks, > > > > > > Nicolai