Re: [tip:x86/boot] x86/mm: Enable KASLR for physical mapping memory regions

From: Borislav Petkov
Date: Tue Aug 16 2016 - 09:49:53 EST


On Tue, Aug 16, 2016 at 03:42:05PM +0200, Borislav Petkov wrote:
> I'll try to reproduce and fix this at some point but am away currently
> so don't hold your breath. Does "dis_ucode_ldr" on the kernel cmdline
> get you any further?

Just a stab in the dark: does something like that help?

---
diff --git a/arch/x86/kernel/cpu/microcode/amd.c b/arch/x86/kernel/cpu/microcode/amd.c
index 27a0228c9cae..2debaf119baf 100644
--- a/arch/x86/kernel/cpu/microcode/amd.c
+++ b/arch/x86/kernel/cpu/microcode/amd.c
@@ -434,6 +434,10 @@ int __init save_microcode_in_initrd_amd(void)
else
container = cont_va;

+#ifdef CONFIG_RANDOMIZE_MEMORY
+ container += PAGE_OFFSET - __PAGE_OFFSET_BASE;
+#endif
+
eax = cpuid_eax(0x00000001);
eax = ((eax >> 8) & 0xf) + ((eax >> 20) & 0xff);

---

Thanks.

--
Regards/Gruss,
Boris.

ECO tip #101: Trim your mails when you reply.
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