diff options
| author | Pawan Gupta <pawan.kumar.gupta@linux.intel.com> | 2025-06-11 10:30:03 -0700 |
|---|---|---|
| committer | Borislav Petkov (AMD) <bp@alien8.de> | 2025-06-23 12:26:57 +0200 |
| commit | 8374a2719df2a00781e6821e373d7de71390d1b4 (patch) | |
| tree | 4518b09781127deaa4e857daa1a6437e6b63fcef /arch/x86/kernel/cpu/bugs.c | |
| parent | 7e44909e0ea8346ba08b244ecc275fc3394e2b8e (diff) | |
x86/bugs: Introduce cdt_possible()
In preparation to allow ITS to also enable stuffing aka Call Depth
Tracking (CDT) independently of retbleed, introduce a helper
cdt_possible().
Signed-off-by: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/20250611-eibrs-fix-v4-5-5ff86cac6c61@linux.intel.com
Diffstat (limited to 'arch/x86/kernel/cpu/bugs.c')
| -rw-r--r-- | arch/x86/kernel/cpu/bugs.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index e861e8884d6b..387610ad222d 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1119,6 +1119,19 @@ early_param("nospectre_v1", nospectre_v1_cmdline); enum spectre_v2_mitigation spectre_v2_enabled __ro_after_init = SPECTRE_V2_NONE; +/* Depends on spectre_v2 mitigation selected already */ +static inline bool cdt_possible(enum spectre_v2_mitigation mode) +{ + if (!IS_ENABLED(CONFIG_MITIGATION_CALL_DEPTH_TRACKING) || + !IS_ENABLED(CONFIG_MITIGATION_RETPOLINE)) + return false; + + if (mode == SPECTRE_V2_RETPOLINE) + return true; + + return false; +} + #undef pr_fmt #define pr_fmt(fmt) "RETBleed: " fmt @@ -1267,7 +1280,7 @@ static void __init retbleed_update_mitigation(void) retbleed_mitigation = RETBLEED_MITIGATION_STUFF; if (retbleed_mitigation == RETBLEED_MITIGATION_STUFF && - spectre_v2_enabled != SPECTRE_V2_RETPOLINE) { + !cdt_possible(spectre_v2_enabled)) { pr_err("WARNING: retbleed=stuff depends on spectre_v2=retpoline\n"); retbleed_mitigation = RETBLEED_MITIGATION_NONE; } |