[PATCH] x86/cpu: clear X86_BUG_SPECTRE_V2 on Zhaoxin family 7 CPUs

[Tony W Wang-oc]

These CPUs are not affected by spectre_v2, so clear spectre_v2 bug flag
in their specific initialization code.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@xxxxxxxxxxx>
---
 arch/x86/kernel/cpu/centaur.c | 5 +++++
 arch/x86/kernel/cpu/zhaoxin.c | 5 +++++
 2 files changed, 10 insertions(+)

diff --git a/arch/x86/kernel/cpu/centaur.c b/arch/x86/kernel/cpu/centaur.c
index b98529e..3567560 100644
--- a/arch/x86/kernel/cpu/centaur.c
+++ b/arch/x86/kernel/cpu/centaur.c
@@ -250,6 +250,11 @@ static void init_centaur(struct cpuinfo_x86 *c)
 
 	if (cpu_has(c, X86_FEATURE_VMX))
 		centaur_detect_vmx_virtcap(c);
+
+	if (c->x86 == 7) {
+		setup_clear_cpu_cap(X86_BUG_SPECTRE_V2);
+		clear_bit(X86_BUG_SPECTRE_V2, (unsigned long *)cpu_caps_set);
+	}
 }
 
 #ifdef CONFIG_X86_32
diff --git a/arch/x86/kernel/cpu/zhaoxin.c b/arch/x86/kernel/cpu/zhaoxin.c
index 452fd0a..ea7c52f 100644
--- a/arch/x86/kernel/cpu/zhaoxin.c
+++ b/arch/x86/kernel/cpu/zhaoxin.c
@@ -141,6 +141,11 @@ static void init_zhaoxin(struct cpuinfo_x86 *c)
 
 	if (cpu_has(c, X86_FEATURE_VMX))
 		zhaoxin_detect_vmx_virtcap(c);
+
+	if (c->x86 == 7) {
+		setup_clear_cpu_cap(X86_BUG_SPECTRE_V2);
+		clear_bit(X86_BUG_SPECTRE_V2, (unsigned long *)cpu_caps_set);
+	}
 }
 
 #ifdef CONFIG_X86_32
-- 
2.7.4