Restructure spectre_v1 to use select/apply functions to create
consistent vulnerability handling.

Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
 arch/x86/kernel/cpu/bugs.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 37056bdd3a9b..ea50c77ccb70 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -54,6 +54,7 @@
  */
 
 static void __init spectre_v1_select_mitigation(void);
+static void __init spectre_v1_apply_mitigation(void);
 static void __init spectre_v2_select_mitigation(void);
 static void __init retbleed_select_mitigation(void);
 static void __init spectre_v2_user_select_mitigation(void);
@@ -216,6 +217,7 @@ void __init cpu_select_mitigations(void)
 	mmio_update_mitigation();
 	rfds_update_mitigation();
 
+	spectre_v1_apply_mitigation();
 	mds_apply_mitigation();
 	taa_apply_mitigation();
 	mmio_apply_mitigation();
@@ -989,10 +991,14 @@ 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) || cpu_mitigations_off())
 		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())
 		return;
-	}
 
 	if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_AUTO) {
 		/*
-- 
2.34.1

On Tue, Nov 05, 2024 at 03:54:31PM -0600, David Kaplan wrote:
>  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) || cpu_mitigations_off())
>  		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())

We probably don't need to repeat this check, is this okay:

	if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_NONE)
>  		return;
> -	}
>  
>  	if (spectre_v1_mitigation == SPECTRE_V1_MITIGATION_AUTO) {