Re: [PATCH] arch/x86/kernel/cpu/microcode/intel: don't store initrd's start

[Borislav Petkov]

On Mon, Jul 25, 2016 at 11:24:31AM +0200, Nicolai Stange wrote:
> I tested on linux-next-20160722 (I wrote this below the '---' marker).

Ok, thanks.

So let's try something simpler first. That works in my kvm guest here,
can you test it on your box too please?

---
diff --git a/arch/x86/kernel/cpu/microcode/intel.c 
b/arch/x86/kernel/cpu/microcode/intel.c
index 6515c802346a..b98e016ba5fc 100644
--- a/arch/x86/kernel/cpu/microcode/intel.c
+++ b/arch/x86/kernel/cpu/microcode/intel.c
@@ -793,10 +793,10 @@ void __init load_ucode_intel_bsp(void)
 void load_ucode_intel_ap(void)
 {
        struct ucode_blobs *blobs_p;
+       unsigned long *ptrs, start;
        struct mc_saved_data *mcs;
        struct ucode_cpu_info uci;
        enum ucode_state ret;
-       unsigned long *ptrs;
 
 #ifdef CONFIG_X86_32
        mcs     = (struct mc_saved_data *)__pa_nodebug(&mc_saved_data);
@@ -815,8 +815,14 @@ void load_ucode_intel_ap(void)
        if (!mcs->num_saved)
                return;
 
+       /*
+        * Pay attention to CONFIG_RANDOMIZE_MEMORY as it shuffles physmem
+        * mapping too.
+        */
+       start = blobs_p->start + (PAGE_OFFSET - __PAGE_OFFSET_BASE);
+
        collect_cpu_info_early(&uci);
-       ret = load_microcode(mcs, ptrs, blobs_p->start, &uci);
+       ret = load_microcode(mcs, ptrs, start, &uci);
        if (ret != UCODE_OK)
                return;
 
---

-- 
Regards/Gruss,
    Boris.

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