[RFC PATCH 31/34] x86/bugs: Add attack vector controls for spectre_v2

[David Kaplan <david.kaplan@amd.com>]

Use attack vector controls to determine if spectre_v2 mitigation is
required.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
 arch/x86/kernel/cpu/bugs.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index cc26f5680523..9c920e2b4f33 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1957,13 +1957,15 @@ static void __init spectre_v2_select_mitigation(void)
 	case SPECTRE_V2_CMD_NONE:
 		return;
 
-	case SPECTRE_V2_CMD_FORCE:
 	case SPECTRE_V2_CMD_AUTO:
+		if (!should_mitigate_vuln(SPECTRE_V2))
+			break;
+		fallthrough;
+	case SPECTRE_V2_CMD_FORCE:
 		if (boot_cpu_has(X86_FEATURE_IBRS_ENHANCED)) {
 			mode = SPECTRE_V2_EIBRS;
 			break;
 		}
-
 		mode = spectre_v2_select_retpoline();
 		break;
 
-- 
2.34.1