From: Jiaxun Yang <jiaxun.yang@flygoat.com>
Date: Tue, 20 Nov 2018 11:00:18 +0800
Subject: x86/CPU/AMD: Set the CPB bit unconditionally on F17h
Git-commit: 0237199186e7a4aa5310741f0a6498a20c820fd7
Patch-mainline: v5.1-rc1
References: bsc#1114279

Some F17h models do not have CPB set in CPUID even though the CPU
supports it. Set the feature bit unconditionally on all F17h.

 [ bp: Rewrite commit message and patch. ]

Signed-off-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Sherry Hurwitz <sherry.hurwitz@amd.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/20181120030018.5185-1-jiaxun.yang@flygoat.com
---
 arch/x86/kernel/cpu/amd.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -824,6 +824,10 @@ static void init_amd_bd(struct cpuinfo_x
 static void init_amd_zn(struct cpuinfo_x86 *c)
 {
 	set_cpu_cap(c, X86_FEATURE_ZEN);
+
+	/* Fix erratum 1076: CPB feature bit not being set in CPUID. */
+	if (!cpu_has(c, X86_FEATURE_CPB))
+		set_cpu_cap(c, X86_FEATURE_CPB);
 }
 
 static void init_amd(struct cpuinfo_x86 *c)