From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030248AbcLPQXn (ORCPT ); Fri, 16 Dec 2016 11:23:43 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:26319 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030226AbcLPQXf (ORCPT ); Fri, 16 Dec 2016 11:23:35 -0500 From: Boris Ostrovsky To: bp@alien8.de Cc: x86@kernel.org, linux-kernel@vger.kernel.org, jgross@suse.com, xen-devel@lists.xenproject.org, Boris Ostrovsky Subject: [PATCH] x86/microcode: Use native_cpuid() in load_ucode_amd_bsp() Date: Fri, 16 Dec 2016 11:39:52 -0500 Message-Id: <1481906392-3847-1-git-send-email-boris.ostrovsky@oracle.com> X-Mailer: git-send-email 1.7.1 X-Source-IP: aserv0021.oracle.com [141.146.126.233] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When CONFIG_PARAVIRT is selected, cpuid() becomes a call. Since for 32-bit kernels load_ucode_amd_bsp() is executed before paging is enabled the call cannot be completed (as kernel virtual addresses are not reachable yet). Use native_cpuid() instead which is an asm wrapper for CPUID instruction. Signed-off-by: Boris Ostrovsky --- arch/x86/kernel/cpu/microcode/amd.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 6f353bd..e2d941f 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -297,6 +297,7 @@ void __init load_ucode_amd_bsp(unsigned int family) struct cpio_data cp; const char *path; bool use_pa; + u32 eax, ebx, ecx, edx; if (IS_ENABLED(CONFIG_X86_32)) { uci = (struct ucode_cpu_info *)__pa_nodebug(ucode_cpu_info); @@ -315,7 +316,10 @@ void __init load_ucode_amd_bsp(unsigned int family) return; /* Get BSP's CPUID.EAX(1), needed in load_microcode_amd() */ - uci->cpu_sig.sig = cpuid_eax(1); + eax = 0x00000001; + ecx = 0; + native_cpuid(&eax, &ebx, &ecx, &edx); + uci->cpu_sig.sig = eax; apply_microcode_early_amd(cp.data, cp.size, true); } -- 1.7.1