From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753978AbbFDRCe (ORCPT ); Thu, 4 Jun 2015 13:02:34 -0400 Received: from mail.skyhub.de ([78.46.96.112]:51678 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754052AbbFDQzj (ORCPT ); Thu, 4 Jun 2015 12:55:39 -0400 From: Borislav Petkov To: Ingo Molnar Cc: LKML Subject: [PATCH 19/20] x86/microcode: Disable builtin microcode loading on 32-bit for now Date: Thu, 4 Jun 2015 18:55:27 +0200 Message-Id: <1433436928-31903-20-git-send-email-bp@alien8.de> X-Mailer: git-send-email 2.3.5 In-Reply-To: <1433436928-31903-1-git-send-email-bp@alien8.de> References: <1433436928-31903-1-git-send-email-bp@alien8.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov Andy Shevchenko reported machine freezes when booting latest tip on x32 setups. Problem is, the builtin microcode handling cannot really work that early, when we haven't even enabled paging. A proper fix would involve handling that case specially as every other early 32-bit boot case in the microcode loader and would require much more involved changes for which it is too late now, more than a week before the upcoming merge window. So, disable the builtin microcode loading only on 32-bit for now. Reported-and-tested-by: Andy Shevchenko Cc: Mika Westerberg Cc: Link: http://lkml.kernel.org/r/1433257003-159485-1-git-send-email-andriy.shevchenko@linux.intel.com Signed-off-by: Borislav Petkov --- arch/x86/kernel/cpu/microcode/amd_early.c | 4 ++++ arch/x86/kernel/cpu/microcode/intel_early.c | 4 ++++ 2 files changed, 8 insertions(+) diff --git a/arch/x86/kernel/cpu/microcode/amd_early.c b/arch/x86/kernel/cpu/microcode/amd_early.c index 9208a36d0f03..9243cd839829 100644 --- a/arch/x86/kernel/cpu/microcode/amd_early.c +++ b/arch/x86/kernel/cpu/microcode/amd_early.c @@ -230,6 +230,7 @@ static void apply_ucode_in_initrd(void *ucode, size_t size, bool save_patch) static bool __init load_builtin_amd_microcode(struct cpio_data *cp, int family) { +#ifdef CONFIG_X86_64 char fw_name[36] = "amd-ucode/microcode_amd.bin"; if (family >= 0x15) @@ -237,6 +238,9 @@ static bool __init load_builtin_amd_microcode(struct cpio_data *cp, int family) "amd-ucode/microcode_amd_fam%.2xh.bin", family); return get_builtin_firmware(cp, fw_name); +#else + return false; +#endif } void __init load_ucode_amd_bsp(int family) diff --git a/arch/x86/kernel/cpu/microcode/intel_early.c b/arch/x86/kernel/cpu/microcode/intel_early.c index 10dff3f3f686..b4858d892592 100644 --- a/arch/x86/kernel/cpu/microcode/intel_early.c +++ b/arch/x86/kernel/cpu/microcode/intel_early.c @@ -523,6 +523,7 @@ EXPORT_SYMBOL_GPL(save_mc_for_early); static bool __init load_builtin_intel_microcode(struct cpio_data *cp) { +#ifdef CONFIG_X86_64 u32 eax = 0x00000001, ebx, ecx = 0, edx; int family, model, stepping; char name[30]; @@ -536,6 +537,9 @@ static bool __init load_builtin_intel_microcode(struct cpio_data *cp) sprintf(name, "intel-ucode/%02x-%02x-%02x", family, model, stepping); return get_builtin_firmware(cp, name); +#else + return false; +#endif } static __initdata char ucode_name[] = "kernel/x86/microcode/GenuineIntel.bin"; -- 2.3.5