Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967303Ab3E3CRA (ORCPT ); Wed, 29 May 2013 22:17:00 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:37635 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966496Ab3E3CQv (ORCPT ); Wed, 29 May 2013 22:16:51 -0400 Subject: Re: [regression, bisected] x86: efi: Pass boot services variable info to runtime code From: joeyli To: Jiri Kosina Cc: Russ Anderson , Matt Fleming , Matthew Garrett , matt.fleming@intel.com, linux-efi@vger.kernel.org, x86@kernel.org, linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Borislav Petkov In-Reply-To: References: <20130522162747.GA20816@sgi.com> <20130523115801.GJ14575@console-pimps.org> <20130523203234.GD20913@sgi.com> <20130524074331.GL14575@console-pimps.org> <20130529210115.GC28027@sgi.com> <20130529224645.GA16582@sgi.com> Content-Type: text/plain; charset="UTF-8" Date: Thu, 30 May 2013 10:16:12 +0800 Message-ID: <1369880172.17397.11.camel@linux-s257.site> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2902 Lines: 76 於 四，2013-05-30 於 00:53 +0200，Jiri Kosina 提到： > On Wed, 29 May 2013, Russ Anderson wrote: > > > > Yes, but this call is clearly happening way before ExitBootServices() -- > > > see the surrounding code, see for example this in efi_main(): > > > > > > [ ... snip ... ] > > > setup_efi_vars(boot_params); > > > > > > setup_efi_pci(boot_params); > > > > > > status = efi_call_phys3(sys_table->boottime->allocate_pool, > > > EFI_LOADER_DATA, sizeof(*gdt), > > > (void **)&gdt); > > > if (status != EFI_SUCCESS) { > > > efi_printk("Failed to alloc mem for gdt structure\n"); > > > goto fail; > > > } > > > [ ... snip ... ] > > > > Yes. Note the failing call is sys_table->runtime while all the > > other calls are sys_table->boottime and seem to work. Not sure > > why the sys_table->runtime call has a problem but it may be > > a clue. Could something in the runtime path not be set up??? > > That was my original idea early today as well. My understanding of the > UEFI spec is admittedly limited, but afaics calling runtime method from > boot environment should be a valid thing to do ... ? QueryVariableInfo() is a runtime services, all runtime services should available bother on boot time and runtime: UEFI spec 2.3.1 P.109: Runtime Services Functions that are available before and after any call to ExitBootServices(). These functions are described in Section 7. > > > > We are calling QueryVariableInfo() in setup_efi_vars(), and later on > > > AllocatePool is being called (through boot table). > > > > On my system the QueryVariableInfo() call fails, so AllocatePool() > > is not called in setup_efi_vars(). > > But it's being called later on coming back to efi_main(). That was just a > poor man's demonstration attempt why this code is running before > ExitBootServices() has been called. > Yes, I agreed your point, the space information of EFI_VARIABLE_BOOTSERVICE_ACCESS should still return by QueryVariableInfo() because we call it before ExitBootServices(): arch/x86/boot/compressed/eboot.c efi_main(void *handle, efi_system_table_t *_table, struct boot_params *boot_params) .. sys_table = _table; /* Check if we were booted by the EFI firmware */ if (sys_table->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE) goto fail; boot_params->secure_boot = get_secure_boot(sys_table) /* check does BIOS in secure boot mode */ setup_graphics(boot_params); setup_efi_vars(boot_params); /* Pass boot services variable info to runtime code, call QueryVariableInfo() */ ... status = exit_boot(boot_params, handle); /* call ExitBootServices() */ ... Thanks a lot! Joey Lee -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/