linux-kernel - [tip:x86/microcode] x86, microcode, AMD: Read CPUID(1). EAX on the correct cpu

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <tip-5f5b747282c6cc57b91baba37f76de27398b9e60@git.kernel.org>
Date:	Wed, 22 Aug 2012 16:43:12 -0700
From:	tip-bot for Borislav Petkov <borislav.petkov@....com>
To:	linux-tip-commits@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org, hpa@...or.com, mingo@...nel.org,
	tglx@...utronix.de, hpa@...ux.intel.com, borislav.petkov@....com
Subject: [tip:x86/microcode] x86, microcode, AMD: Read CPUID(1).
 EAX on the correct cpu

Commit-ID:  5f5b747282c6cc57b91baba37f76de27398b9e60
Gitweb:     http://git.kernel.org/tip/5f5b747282c6cc57b91baba37f76de27398b9e60
Author:     Borislav Petkov <borislav.petkov@....com>
AuthorDate: Wed, 25 Jul 2012 20:06:54 +0200
Committer:  H. Peter Anvin <hpa@...ux.intel.com>
CommitDate: Wed, 22 Aug 2012 16:15:50 -0700

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: Borislav Petkov <borislav.petkov@....com>
Link: http://lkml.kernel.org/r/1344361461-10076-9-git-send-email-bp@amd64.org
Signed-off-by: H. Peter Anvin <hpa@...ux.intel.com>
---
 arch/x86/kernel/microcode_amd.c |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/microcode_amd.c b/arch/x86/kernel/microcode_amd.c
index 8fdf7d9..25d34b1 100644
--- a/arch/x86/kernel/microcode_amd.c
+++ b/arch/x86/kernel/microcode_amd.c
@@ -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;
 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/