Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753151AbdFLPcD (ORCPT ); Mon, 12 Jun 2017 11:32:03 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:40538 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753775AbdFLPcA (ORCPT ); Mon, 12 Jun 2017 11:32:00 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dominik Brodowski , Borislav Petkov , Linus Torvalds , Peter Zijlstra , Thomas Gleixner , Ingo Molnar Subject: [PATCH 4.11 132/150] x86/microcode/intel: Clear patch pointer before jettisoning the initrd Date: Mon, 12 Jun 2017 17:25:39 +0200 Message-Id: <20170612152525.510597198@linuxfoundation.org> X-Mailer: git-send-email 2.13.1 In-Reply-To: <20170612152519.404936272@linuxfoundation.org> References: <20170612152519.404936272@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1626 Lines: 48 4.11-stable review patch. If anyone has any objections, please let me know. ------------------ From: Dominik Brodowski commit 5b0bc9ac2ce4881ee318a21f31140584ce4dbdad upstream. During early boot, load_ucode_intel_ap() uses __load_ucode_intel() to obtain a pointer to the relevant microcode patch (embedded in the initrd), and stores this value in 'intel_ucode_patch' to speed up the microcode patch application for subsequent CPUs. On resuming from suspend-to-RAM, however, load_ucode_ap() calls load_ucode_intel_ap() for each non-boot-CPU. By then the initramfs is long gone so the pointer stored in 'intel_ucode_patch' no longer points to a valid microcode patch. Clear that pointer so that we effectively fall back to the CPU hotplug notifier callbacks to update the microcode. Signed-off-by: Dominik Brodowski [ Edit and massage commit message. ] Signed-off-by: Borislav Petkov Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20170607095819.9754-1-bp@alien8.de Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/microcode/intel.c | 3 +++ 1 file changed, 3 insertions(+) --- a/arch/x86/kernel/cpu/microcode/intel.c +++ b/arch/x86/kernel/cpu/microcode/intel.c @@ -619,6 +619,9 @@ int __init save_microcode_in_initrd_inte show_saved_mc(); + /* initrd is going away, clear patch ptr. */ + intel_ucode_patch = NULL; + return 0; }