amd64_edac: check NB MCE bank enable on the current node properly

The old code was using smp_call_function_many which skips the current
cpu if it is in the supplied cpumask. Switch to the rdmsr_on_cpus()
interface which takes care of that.

In addition, add get_cpus_on_this_dct_cpumask helper which computes a
cpumask of all the cores on a node and thus on a DCT.

Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>

1 files changed, 45 insertions, 21 deletions

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index f943ad89849f..4e551e63b6dc 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -2741,30 +2741,53 @@ static void amd64_restore_ecc_error_reporting(struct amd64_pvt *pvt)
         wrmsr_on_cpus(cpumask, K8_MSR_MCGCTL, msrs);
 }
 
-static void check_mcg_ctl(void *ret)
+/* get all cores on this DCT */
+static void get_cpus_on_this_dct_cpumask(cpumask_t *mask, int nid)
 {
-        u64 msr_val = 0;
-        u8 nbe;
+        int cpu;
 
-        rdmsrl(MSR_IA32_MCG_CTL, msr_val);
-        nbe = msr_val & K8_MSR_MCGCTL_NBE;
-
-        debugf0("core: %u, MCG_CTL: 0x%llx, NB MSR is %s\n",
-                raw_smp_processor_id(), msr_val,
-                (nbe ? "enabled" : "disabled"));
-
-        if (!nbe)
-                *(int *)ret = 0;
+        for_each_online_cpu(cpu)
+                if (amd_get_nb_id(cpu) == nid)
+                        cpumask_set_cpu(cpu, mask);
 }
 
 /* check MCG_CTL on all the cpus on this node */
-static int mcg_ctl_enabled_on_node(const struct cpumask *mask)
+static bool amd64_nb_mce_bank_enabled_on_node(int nid)
 {
-        int ret = 1;
-        preempt_disable();
-        smp_call_function_many(mask, check_mcg_ctl, &ret, 1);
-        preempt_enable();
+        cpumask_t mask;
+        struct msr *msrs;
+        int cpu, nbe, idx = 0;
+        bool ret = false;
+
+        cpumask_clear(&mask);
+
+        get_cpus_on_this_dct_cpumask(&mask, nid);
+
+        msrs = kzalloc(sizeof(struct msr) * cpumask_weight(&mask), GFP_KERNEL);
+        if (!msrs) {
+                amd64_printk(KERN_WARNING, "%s: error allocating msrs\n",
+                              __func__);
+                 return false;
+        }
+
+        rdmsr_on_cpus(&mask, MSR_IA32_MCG_CTL, msrs);
+
+        for_each_cpu(cpu, &mask) {
+                nbe = msrs[idx].l & K8_MSR_MCGCTL_NBE;
+
+                debugf0("core: %u, MCG_CTL: 0x%llx, NB MSR is %s\n",
+                        cpu, msrs[idx].q,
+                        (nbe ? "enabled" : "disabled"));
+
+                if (!nbe)
+                        goto out;
+
+                idx++;
+        }
+        ret = true;
 
+out:
+        kfree(msrs);
         return ret;
 }
 
@@ -2783,7 +2806,8 @@ static int amd64_check_ecc_enabled(struct amd64_pvt *pvt)
 {
         u32 value;
         int err = 0;
-        u8 ecc_enabled = 0, mcg_ctl_en = 0;
+        u8 ecc_enabled = 0;
+        bool nb_mce_en = false;
 
         err = pci_read_config_dword(pvt->misc_f3_ctl, K8_NBCFG, &value);
         if (err)
@@ -2797,13 +2821,13 @@ static int amd64_check_ecc_enabled(struct amd64_pvt *pvt)
         else
                 amd64_printk(KERN_INFO, "ECC is enabled by BIOS.\n");
 
-        mcg_ctl_en = mcg_ctl_enabled_on_node(cpumask_of_node(pvt->mc_node_id));
-        if (!mcg_ctl_en)
+        nb_mce_en = amd64_nb_mce_bank_enabled_on_node(pvt->mc_node_id);
+        if (!nb_mce_en)
                 amd64_printk(KERN_WARNING, "NB MCE bank disabled, set MSR "
                              "0x%08x[4] on node %d to enable.\n",
                              MSR_IA32_MCG_CTL, pvt->mc_node_id);
 
-        if (!ecc_enabled || !mcg_ctl_en) {
+        if (!ecc_enabled || !nb_mce_en) {
                 if (!ecc_enable_override) {
                         amd64_printk(KERN_WARNING, "%s", ecc_warning);
                         return -ENODEV;