diff options
Diffstat (limited to 'kernel/cpu.c')
| -rw-r--r-- | kernel/cpu.c | 34 |
1 files changed, 33 insertions, 1 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 127a69b8b192..49273130e4f1 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -376,6 +376,7 @@ void __init cpu_smt_disable(bool force) pr_info("SMT: Force disabled\n"); cpu_smt_control = CPU_SMT_FORCE_DISABLED; } else { + pr_info("SMT: disabled\n"); cpu_smt_control = CPU_SMT_DISABLED; } } @@ -1944,6 +1945,9 @@ static ssize_t write_cpuhp_fail(struct device *dev, if (ret) return ret; + if (fail < CPUHP_OFFLINE || fail > CPUHP_ONLINE) + return -EINVAL; + /* * Cannot fail STARTING/DYING callbacks. */ @@ -2298,7 +2302,18 @@ void __init boot_cpu_hotplug_init(void) this_cpu_write(cpuhp_state.state, CPUHP_ONLINE); } -enum cpu_mitigations cpu_mitigations __ro_after_init = CPU_MITIGATIONS_AUTO; +/* + * These are used for a global "mitigations=" cmdline option for toggling + * optional CPU mitigations. + */ +enum cpu_mitigations { + CPU_MITIGATIONS_OFF, + CPU_MITIGATIONS_AUTO, + CPU_MITIGATIONS_AUTO_NOSMT, +}; + +static enum cpu_mitigations cpu_mitigations __ro_after_init = + CPU_MITIGATIONS_AUTO; static int __init mitigations_parse_cmdline(char *arg) { @@ -2308,7 +2323,24 @@ static int __init mitigations_parse_cmdline(char *arg) cpu_mitigations = CPU_MITIGATIONS_AUTO; else if (!strcmp(arg, "auto,nosmt")) cpu_mitigations = CPU_MITIGATIONS_AUTO_NOSMT; + else + pr_crit("Unsupported mitigations=%s, system may still be vulnerable\n", + arg); return 0; } early_param("mitigations", mitigations_parse_cmdline); + +/* mitigations=off */ +bool cpu_mitigations_off(void) +{ + return cpu_mitigations == CPU_MITIGATIONS_OFF; +} +EXPORT_SYMBOL_GPL(cpu_mitigations_off); + +/* mitigations=auto,nosmt */ +bool cpu_mitigations_auto_nosmt(void) +{ + return cpu_mitigations == CPU_MITIGATIONS_AUTO_NOSMT; +} +EXPORT_SYMBOL_GPL(cpu_mitigations_auto_nosmt); |