diff --git a/sys/x86/include/mca.h b/sys/x86/include/mca.h
--- a/sys/x86/include/mca.h
+++ b/sys/x86/include/mca.h
@@ -46,6 +46,11 @@
 
 #ifdef _KERNEL
 
+typedef void (*mca_decode_func)(void*, const struct mca_record*);
+
+int	mca_register_decode_func(mca_decode_func func, void *aux);
+int	mca_deregister_decode_func(mca_decode_func func);
+
 void	cmc_intr(void);
 void	mca_init(void);
 void	mca_intr(void);
diff --git a/sys/x86/x86/mca.c b/sys/x86/x86/mca.c
--- a/sys/x86/x86/mca.c
+++ b/sys/x86/x86/mca.c
@@ -99,6 +99,8 @@
 static volatile int mca_count;	/* Number of records stored. */
 static int mca_banks;		/* Number of per-CPU register banks. */
 static int mca_maxcount = -1;	/* Limit on records stored. (-1 = unlimited) */
+static mca_decode_func mca_func;
+static void *mca_decode_arg;
 
 static SYSCTL_NODE(_hw, OID_AUTO, mca, CTLFLAG_RD | CTLFLAG_MPSAFE, NULL,
     "Machine Check Architecture");
@@ -421,10 +423,45 @@
 	return (0);
 }
 
+int
+mca_register_decode_func(mca_decode_func func, void *arg)
+{
+	int error = 0;
+
+	KASSERT(func != NULL, ("missing decode function"));
+
+	mtx_lock_spin(&mca_lock);
+	if (mca_func == NULL) {
+		mca_decode_arg = arg;
+		atomic_set_ptr((uintptr_t *)&mca_func, (uintptr_t)func);
+	} else
+		error = EEXIST;
+	mtx_unlock_spin(&mca_lock);
+
+	return (error);
+}
+
+int
+mca_deregister_decode_func(mca_decode_func func)
+{
+	int error = 0;
+
+	KASSERT(func != NULL, ("missing decode function"));
+
+	mtx_lock_spin(&mca_lock);
+	if (!atomic_cmpset_acq_ptr((uintptr_t *)&mca_func, (uintptr_t)func,
+	    (uintptr_t)NULL))
+		error = EINVAL;
+	mtx_unlock_spin(&mca_lock);
+
+	return (error);
+}
+
 /* Dump details about a single machine check. */
 static void
 mca_log(const struct mca_record *rec)
 {
+	mca_decode_func decode_func;
 	uint16_t mca_error;
 
 	if (mca_mute(rec))
@@ -613,6 +650,14 @@
 	}
 	if (rec->mr_status & MC_STATUS_MISCV)
 		printf("MCA: Misc 0x%llx\n", (long long)rec->mr_misc);
+
+	/*
+	 * Pass record to a memory controller driver so that it can
+	 * decode the address.
+	 */
+	decode_func = atomic_load_ptr(&mca_func);
+	if (decode_func != NULL)
+		decode_func(mca_decode_arg, rec);
 }
 
 static bool