From 88b2f634028f1f38dcc3d412e10ff1f224976daa Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Wed, 17 Aug 2016 13:33:14 +0200 Subject: [PATCH] x86/microcode/AMD: Fix initrd loading with CONFIG_RANDOMIZE_MEMORY=y Similar to: efaad554b4ff ("x86/microcode/intel: Fix initrd loading with CONFIG_RANDOMIZE_MEMORY=y") ... fix microcode loading from the initrd on AMD by adding the randomization offset to the microcode patch container within the initrd. Reported-and-tested-by: Brian Gerst Signed-off-by: Borislav Petkov Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Kees Cook Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-tip-commits@vger.kernel.org Link: http://lkml.kernel.org/r/20160817113314.GA19221@nazgul.tnic Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/microcode/amd.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c index 27a0228c9cae..b816971f5da4 100644 --- a/arch/x86/kernel/cpu/microcode/amd.c +++ b/arch/x86/kernel/cpu/microcode/amd.c @@ -355,6 +355,7 @@ void load_ucode_amd_ap(void) unsigned int cpu = smp_processor_id(); struct equiv_cpu_entry *eq; struct microcode_amd *mc; + u8 *cont = container; u32 rev, eax; u16 eq_id; @@ -371,8 +372,11 @@ void load_ucode_amd_ap(void) if (check_current_patch_level(&rev, false)) return; + /* Add CONFIG_RANDOMIZE_MEMORY offset. */ + cont += PAGE_OFFSET - __PAGE_OFFSET_BASE; + eax = cpuid_eax(0x00000001); - eq = (struct equiv_cpu_entry *)(container + CONTAINER_HDR_SZ); + eq = (struct equiv_cpu_entry *)(cont + CONTAINER_HDR_SZ); eq_id = find_equiv_id(eq, eax); if (!eq_id) @@ -434,6 +438,9 @@ int __init save_microcode_in_initrd_amd(void) else container = cont_va; + /* Add CONFIG_RANDOMIZE_MEMORY offset. */ + container += PAGE_OFFSET - __PAGE_OFFSET_BASE; + eax = cpuid_eax(0x00000001); eax = ((eax >> 8) & 0xf) + ((eax >> 20) & 0xff);