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Commit 5f5b7472 authored by Borislav Petkov's avatar Borislav Petkov Committed by H. Peter Anvin
Browse files

x86, microcode, AMD: Read CPUID(1).EAX on the correct cpu 



Read the CPUID(1).EAX leaf at the correct cpu and use it to search the
equivalence table for matching microcode patch. No functionality change.

Signed-off-by: default avatarBorislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/1344361461-10076-9-git-send-email-bp@amd64.org


Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 685ca6d7

arch/x86/kernel/microcode_amd.c

+6 −6
Original line number Diff line number Diff line
@@ -82,6 +82,7 @@ static int collect_cpu_info_amd(int cpu, struct cpu_signature *csig) 
{

	struct cpuinfo_x86 *c = &cpu_data(cpu);



	csig->sig = cpuid_eax(0x00000001);

	csig->rev = c->microcode;

	pr_info("CPU%d: patch_level=0x%08x\n", cpu, csig->rev);
@@ -118,16 +119,15 @@ static unsigned int verify_ucode_size(int cpu, u32 patch_size, 
	return patch_size;

}



static u16 find_equiv_id(void)

static u16 find_equiv_id(unsigned int cpu)

{

	unsigned int current_cpu_id, i = 0;

	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;

	int i = 0;



	BUG_ON(equiv_cpu_table == NULL);



	current_cpu_id = cpuid_eax(0x00000001);



	while (equiv_cpu_table[i].installed_cpu != 0) {

		if (current_cpu_id == equiv_cpu_table[i].installed_cpu)

		if (uci->cpu_sig.sig == equiv_cpu_table[i].installed_cpu)

			return equiv_cpu_table[i].equiv_cpu;



		i++;
@@ -150,7 +150,7 @@ static int get_matching_microcode(int cpu, const u8 *ucode_ptr, 
	patch_size = *(u32 *)(ucode_ptr + 4);

	*current_size = patch_size + SECTION_HDR_SIZE;



	equiv_cpu_id = find_equiv_id();

	equiv_cpu_id = find_equiv_id(cpu);

	if (!equiv_cpu_id)

		return 0;