From 5b0bc9ac2ce4881ee318a21f31140584ce4dbdad Mon Sep 17 00:00:00 2001 From: Dominik Brodowski Date: Wed, 7 Jun 2017 11:58:19 +0200 Subject: [PATCH] x86/microcode/intel: Clear patch pointer before jettisoning the initrd 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: # 4.10.. 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 --- arch/x86/kernel/cpu/microcode/intel.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/x86/kernel/cpu/microcode/intel.c b/arch/x86/kernel/cpu/microcode/intel.c index afdfd237b59f..f522415bf9e5 100644 --- 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_intel(void) show_saved_mc(); + /* initrd is going away, clear patch ptr. */ + intel_ucode_patch = NULL; + return 0; } -- 2.20.1