Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932168Ab3FFHlw (ORCPT ); Thu, 6 Jun 2013 03:41:52 -0400 Received: from smtp.nue.novell.com ([195.135.221.5]:39115 "EHLO smtp.nue.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754448Ab3FFHlu (ORCPT ); Thu, 6 Jun 2013 03:41:50 -0400 Subject: Re: [PATCH] Modify UEFI anti-bricking code From: joeyli To: Matthew Garrett Cc: Matt Fleming , "Fleming, Matt" , "rja@sgi.com" , "mingo@kernel.org" , "torvalds@linux-foundation.org" , "bp@alien8.de" , "jkosina@suse.cz" , "linux-efi@vger.kernel.org" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "tglx@linutronix.de" , "hpa@linux.intel.com" , "akpm@linux-foundation.org" , "oneukum@suse.de" In-Reply-To: <1370497321.6315.44.camel@x230.lan> References: <1370117180-1712-1-git-send-email-matthew.garrett@nebula.com> <1370276021.30695.4.camel@linux-s257.site> <1370277079.6315.14.camel@x230.lan> <1370316933.30695.7.camel@linux-s257.site> <1370444007.6315.32.camel@x230.lan> <20130605155904.GC30420@console-pimps.org> <1370495110.6523.35.camel@linux-s257.site> <1370497321.6315.44.camel@x230.lan> Content-Type: text/plain; charset="UTF-8" Date: Thu, 06 Jun 2013 15:40:26 +0800 Message-ID: <1370504426.6523.49.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: 3540 Lines: 106 於 四，2013-06-06 於 05:42 +0000，Matthew Garrett 提到： > On Thu, 2013-06-06 at 13:05 +0800, joeyli wrote: > > > + if (!(attributes & EFI_VARIABLE_NON_VOLATILE)) > > + return EFI_OUT_OF_RESOURCES; > > I'd move this up to the top of the function, and just return 0 - there's > no risk of the firmware causing problems if it's a volatile variable, so > we should probably just pass it down to the firmware and return an error > from there. > OK, I moved volatile checking to the top of the function. New version, version 3 diff result like the following. Thanks a lot for reviewing Joey Lee diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index cc3cfe8..5ae2eb0 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -53,6 +53,8 @@ #define EFI_DEBUG 1 +#define EFI_MIN_RESERVE 5120 + #define EFI_DUMMY_GUID \ EFI_GUID(0x4424ac57, 0xbe4b, 0x47dd, 0x9e, 0x97, 0xed, 0x50, 0xf0, 0x9f, 0x92, 0xa9) @@ -988,7 +990,11 @@ void __init efi_enter_virtual_mode(void) kfree(new_memmap); /* clean DUMMY object */ - efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, 0, 0, NULL); + efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, + EFI_VARIABLE_NON_VOLATILE | + EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS, + 0, NULL); } /* @@ -1040,6 +1046,9 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) efi_status_t status; u64 storage_size, remaining_size, max_size; + if (!(attributes & EFI_VARIABLE_NON_VOLATILE)) + return 0; + status = efi.query_variable_info(attributes, &storage_size, &remaining_size, &max_size); if (status != EFI_SUCCESS) @@ -1051,7 +1060,9 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) * write if permitting it would reduce the available space to under * 5KB. This figure was provided by Samsung, so should be safe. */ - if ((remaining_size - size < 5120) && !efi_no_storage_paranoia) { + if ((remaining_size - size < EFI_MIN_RESERVE) && + !efi_no_storage_paranoia) { + /* * Triggering garbage collection may require that the firmware * generate a real EFI_OUT_OF_RESOURCES error. We can force @@ -1061,7 +1072,10 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) void *dummy = kmalloc(dummy_size, GFP_ATOMIC); status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, - attributes, dummy_size, dummy); + EFI_VARIABLE_NON_VOLATILE | + EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS, + dummy_size, dummy); if (status == EFI_SUCCESS) { /* @@ -1069,7 +1083,10 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) * that we delete it... */ efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, - attributes, 0, dummy); + EFI_VARIABLE_NON_VOLATILE | + EFI_VARIABLE_BOOTSERVICE_ACCESS | + EFI_VARIABLE_RUNTIME_ACCESS, + 0, dummy); } /* @@ -1085,7 +1102,7 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) /* * There still isn't enough room, so return an error */ - if (remaining_size - size < 5120) + if (remaining_size - size < EFI_MIN_RESERVE) return EFI_OUT_OF_RESOURCES; } -- 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/