x86/bugs: Add attack vector controls for spectre_v1

Use attack vector controls to determine if spectre_v1 mitigation is
required.

Signed-off-by: David Kaplan <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Link: https://lore.kernel.org/[email protected]

Author: dkaplan2

arch/x86/kernel/cpu/bugs.c

@@ -1144,13 +1144,16 @@ static bool smap_works_speculatively(void)
 
 static void __init spectre_v1_select_mitigation(void)
 {
-	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off())
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1))
+		spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
+
+	if (!should_mitigate_vuln(X86_BUG_SPECTRE_V1))
 		spectre_v1_mitigation = SPECTRE_V1_MITIGATION_NONE;
 }
 
 static void __init spectre_v1_apply_mitigation(void)
 {
-	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1) || cpu_mitigations_off())
+	if (!boot_cpu_has_bug(X86_BUG_SPECTRE_V1))
 		return;
 
 	if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_AUTO) {