x86/cpufeature: Create a new synthetic cpu capability for machine check recovery

[cascardo/linux.git] / arch / x86 / kernel / cpu / mcheck / mce.c

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index a006f4c..b5b187c 100644 (file)
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -1576,6 +1576,17 @@ static int __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c)
 
                if (c->x86 == 6 && c->x86_model == 45)
                        quirk_no_way_out = quirk_sandybridge_ifu;
+               /*
+                * MCG_CAP.MCG_SER_P is necessary but not sufficient to know
+                * whether this processor will actually generate recoverable
+                * machine checks. Check to see if this is an E7 model Xeon.
+                * We can't do a model number check because E5 and E7 use the
+                * same model number. E5 doesn't support recovery, E7 does.
+                */
+               if (mca_cfg.recovery || (mca_cfg.ser &&
+                       !strncmp(c->x86_model_id,
+                                "Intel(R) Xeon(R) CPU E7-", 24)))
+                       set_cpu_cap(c, X86_FEATURE_MCE_RECOVERY);
        }
        if (cfg->monarch_timeout < 0)
                cfg->monarch_timeout = 0;
@@ -2028,6 +2039,8 @@ static int __init mcheck_enable(char *str)
                cfg->bootlog = (str[0] == 'b');
        else if (!strcmp(str, "bios_cmci_threshold"))
                cfg->bios_cmci_threshold = true;
+       else if (!strcmp(str, "recovery"))
+               cfg->recovery = true;
        else if (isdigit(str[0])) {
                if (get_option(&str, &cfg->tolerant) == 2)
                        get_option(&str, &(cfg->monarch_timeout));