x86/bugs: Fix reporting of LFENCE retpoline

JIRA: https://issues.redhat.com/browse/RHEL-119227

commit d1cc1ba
Author: David Kaplan <david.kaplan@amd.com>
Date:   Mon, 15 Sep 2025 08:47:05 -0500

    x86/bugs: Fix reporting of LFENCE retpoline

    The LFENCE retpoline mitigation is not secure but the kernel prints
    inconsistent messages about this fact.  The dmesg log says 'Mitigation:
    LFENCE', implying the system is mitigated.  But sysfs reports 'Vulnerable:
    LFENCE' implying the system (correctly) is not mitigated.

    Fix this by printing a consistent 'Vulnerable: LFENCE' string everywhere
    when this mitigation is selected.

    Signed-off-by: David Kaplan <david.kaplan@amd.com>
    Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
    Link: https://lore.kernel.org/20250915134706.3201818-1-david.kaplan@amd.com

Signed-off-by: Waiman Long <longman@redhat.com>

Author: Waiman-Long

arch/x86/kernel/cpu/bugs.c

@@ -2032,7 +2032,7 @@ static void __init spectre_v2_user_apply_mitigation(void)
 static const char * const spectre_v2_strings[] = {
 	[SPECTRE_V2_NONE]			= "Vulnerable",
 	[SPECTRE_V2_RETPOLINE]			= "Mitigation: Retpolines",
-	[SPECTRE_V2_LFENCE]			= "Mitigation: LFENCE",
+	[SPECTRE_V2_LFENCE]			= "Vulnerable: LFENCE",
 	[SPECTRE_V2_EIBRS]			= "Mitigation: Enhanced / Automatic IBRS",
 	[SPECTRE_V2_EIBRS_LFENCE]		= "Mitigation: Enhanced / Automatic IBRS + LFENCE",
 	[SPECTRE_V2_EIBRS_RETPOLINE]		= "Mitigation: Enhanced / Automatic IBRS + Retpolines",
@@ -3559,9 +3559,6 @@ static const char *spectre_bhi_state(void)
 
 static ssize_t spectre_v2_show_state(char *buf)
 {
-	if (spectre_v2_enabled == SPECTRE_V2_LFENCE)
-		return sysfs_emit(buf, "Vulnerable: LFENCE\n");
-
 	if (spectre_v2_enabled == SPECTRE_V2_EIBRS && unprivileged_ebpf_enabled())
 		return sysfs_emit(buf, "Vulnerable: eIBRS with unprivileged eBPF\n");