From 37f49e37ab4cb5d0bc4c60eb5c6d4dd57db767bb Mon Sep 17 00:00:00 2001 From: hc <hc@nodka.com> Date: Fri, 10 May 2024 07:44:59 +0000 Subject: [PATCH] gmac get mac form eeprom --- kernel/arch/x86/kernel/cpu/rdrand.c | 37 ++++++++++++++++++++++--------------- 1 files changed, 22 insertions(+), 15 deletions(-) diff --git a/kernel/arch/x86/kernel/cpu/rdrand.c b/kernel/arch/x86/kernel/cpu/rdrand.c index cfa97ff..c4be620 100644 --- a/kernel/arch/x86/kernel/cpu/rdrand.c +++ b/kernel/arch/x86/kernel/cpu/rdrand.c @@ -1,23 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * This file is part of the Linux kernel. * * Copyright (c) 2011, Intel Corporation * Authors: Fenghua Yu <fenghua.yu@intel.com>, * H. Peter Anvin <hpa@linux.intel.com> - * - * This program is free software; you can redistribute it and/or modify it - * under the terms and conditions of the GNU General Public License, - * version 2, as published by the Free Software Foundation. - * - * This program is distributed in the hope it will be useful, but WITHOUT - * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or - * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for - * more details. - * - * You should have received a copy of the GNU General Public License along with - * this program; if not, write to the Free Software Foundation, Inc., - * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. - * */ #include <asm/processor.h> @@ -42,7 +29,8 @@ #ifdef CONFIG_ARCH_RANDOM void x86_init_rdrand(struct cpuinfo_x86 *c) { - unsigned long tmp; + unsigned int changed = 0; + unsigned long tmp, prev; int i; if (!cpu_has(c, X86_FEATURE_RDRAND)) @@ -55,5 +43,24 @@ return; } } + + /* + * Stupid sanity-check whether RDRAND does *actually* generate + * some at least random-looking data. + */ + prev = tmp; + for (i = 0; i < SANITY_CHECK_LOOPS; i++) { + if (rdrand_long(&tmp)) { + if (prev != tmp) + changed++; + + prev = tmp; + } + } + + if (WARN_ON_ONCE(!changed)) + pr_emerg( +"RDRAND gives funky smelling output, might consider not using it by booting with \"nordrand\""); + } #endif -- Gitblit v1.6.2