Use attack vector controls to determine if spectre_v2_user mitigation is
required.
Signed-off-by: David Kaplan <david.kaplan@amd.com>
---
arch/x86/kernel/cpu/bugs.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c
index 160dcaa18b04..305a11fa9521 100644
--- a/arch/x86/kernel/cpu/bugs.c
+++ b/arch/x86/kernel/cpu/bugs.c
@@ -1532,7 +1532,7 @@ static enum spectre_v2_user_cmd __init spectre_v2_parse_user_cmdline(void)
char arg[20];
int ret, i;
- if (cpu_mitigations_off() || !IS_ENABLED(CONFIG_MITIGATION_SPECTRE_V2))
+ if (!IS_ENABLED(CONFIG_MITIGATION_SPECTRE_V2))
return SPECTRE_V2_USER_CMD_NONE;
ret = cmdline_find_option(boot_command_line, "spectre_v2_user",
@@ -1570,6 +1570,13 @@ static void __init spectre_v2_user_select_mitigation(void)
spectre_v2_user_stibp = SPECTRE_V2_USER_STRICT;
break;
case SPECTRE_V2_USER_CMD_AUTO:
+ if (!should_mitigate_vuln(X86_BUG_SPECTRE_V2_USER))
+ break;
+ spectre_v2_user_ibpb = SPECTRE_V2_USER_PRCTL;
+ if (smt_mitigations == SMT_MITIGATIONS_OFF)
+ break;
+ spectre_v2_user_stibp = SPECTRE_V2_USER_PRCTL;
+ break;
case SPECTRE_V2_USER_CMD_PRCTL:
spectre_v2_user_ibpb = SPECTRE_V2_USER_PRCTL;
spectre_v2_user_stibp = SPECTRE_V2_USER_PRCTL;
--
2.34.1