diff --git a/sys/cddl/dev/dtrace/dtrace_cddl.h b/sys/cddl/dev/dtrace/dtrace_cddl.h
index 42a4721fbb90..c151c8cf9660 100644
--- a/sys/cddl/dev/dtrace/dtrace_cddl.h
+++ b/sys/cddl/dev/dtrace/dtrace_cddl.h
@@ -79,7 +79,7 @@ typedef struct kdtrace_thread {
 #ifdef __amd64__
 	uintptr_t	td_dtrace_regv;
 #endif
-	uint64_t	td_hrtime;	/* Last time on cpu. */
+	uintptr_t	td_dtrace_sdt_arg[1];	/* Space for extra SDT args */
 	void		*td_dtrace_sscr; /* Saved scratch space location. */
 	void		*td_systrace_args; /* syscall probe arguments. */
 	uint64_t	td_fasttrap_tp_gen; /* Tracepoint hash table gen. */
@@ -110,6 +110,7 @@ typedef struct kdtrace_thread {
 #define	t_dtrace_scrpc	td_dtrace->td_dtrace_scrpc
 #define	t_dtrace_astpc	td_dtrace->td_dtrace_astpc
 #define	t_dtrace_regv	td_dtrace->td_dtrace_regv
+#define	t_dtrace_sdt_arg	td_dtrace->td_dtrace_sdt_arg
 #define	t_dtrace_sscr	td_dtrace->td_dtrace_sscr
 #define	t_dtrace_systrace_args	td_dtrace->td_systrace_args
 #define	t_fasttrap_tp_gen	td_dtrace->td_fasttrap_tp_gen
diff --git a/sys/cddl/dev/sdt/sdt.c b/sys/cddl/dev/sdt/sdt.c
index 51fa0432437c..461f454186a3 100644
--- a/sys/cddl/dev/sdt/sdt.c
+++ b/sys/cddl/dev/sdt/sdt.c
@@ -58,8 +58,11 @@
 #include <sys/dtrace.h>
 #include <sys/dtrace_bsd.h>
 
+#include <cddl/dev/dtrace/dtrace_cddl.h>
+
 /* DTrace methods. */
 static void	sdt_getargdesc(void *, dtrace_id_t, void *, dtrace_argdesc_t *);
+static uint64_t	sdt_getargval(void *, dtrace_id_t, void *, int, int);
 static void	sdt_provide_probes(void *, dtrace_probedesc_t *);
 static void	sdt_destroy(void *, dtrace_id_t, void *);
 static void	sdt_enable(void *, dtrace_id_t, void *);
@@ -93,7 +96,7 @@ static dtrace_pops_t sdt_pops = {
 	.dtps_suspend =		NULL,
 	.dtps_resume =		NULL,
 	.dtps_getargdesc =	sdt_getargdesc,
-	.dtps_getargval =	NULL,
+	.dtps_getargval =	sdt_getargval,
 	.dtps_usermode =	NULL,
 	.dtps_destroy =		sdt_destroy,
 };
@@ -321,6 +324,23 @@ sdt_getargdesc(void *arg, dtrace_id_t id, void *parg, dtrace_argdesc_t *desc)
 	}
 }
 
+/*
+ * Fetch arguments beyond the first five passed directly to dtrace_probe().
+ * FreeBSD's SDT implement currently only supports up to 6 arguments, so we just
+ * need to handle arg5 here.
+ */
+static uint64_t
+sdt_getargval(void *arg __unused, dtrace_id_t id __unused,
+    void *parg __unused, int argno, int aframes __unused)
+{
+	if (argno != 5) {
+		DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
+		return (0);
+	} else {
+		return (curthread->t_dtrace_sdt_arg[argno - 5]);
+	}
+}
+
 static void
 sdt_destroy(void *arg, dtrace_id_t id, void *parg)
 {
@@ -449,14 +469,21 @@ sdt_load_probes_cb(linker_file_t lf, void *arg __unused)
 	return (0);
 }
 
+static void
+sdt_dtrace_probe(dtrace_id_t id, uintptr_t arg0, uintptr_t arg1,
+    uintptr_t arg2, uintptr_t arg3, uintptr_t arg4, uintptr_t arg5)
+{
+	curthread->t_dtrace_sdt_arg[0] = arg5;
+	dtrace_probe(id, arg0, arg1, arg2, arg3, arg4);
+}
+
 static void
 sdt_load(void)
 {
 
 	TAILQ_INIT(&sdt_prov_list);
 
-	sdt_probe_func = dtrace_probe;
-	sdt_probe6_func = (sdt_probe6_func_t)dtrace_probe;
+	sdt_probe_func = sdt_dtrace_probe;
 
 	sdt_kld_load_tag = EVENTHANDLER_REGISTER(kld_load, sdt_kld_load, NULL,
 	    EVENTHANDLER_PRI_ANY);
@@ -482,7 +509,6 @@ sdt_unload(void)
 	EVENTHANDLER_DEREGISTER(kld_unload_try, sdt_kld_unload_try_tag);
 
 	sdt_probe_func = sdt_probe_stub;
-	sdt_probe6_func = (sdt_probe6_func_t)sdt_probe_stub;
 
 	TAILQ_FOREACH_SAFE(prov, &sdt_prov_list, prov_entry, tmp) {
 		ret = dtrace_unregister(prov->id);
@@ -515,3 +541,4 @@ SYSUNINIT(sdt_unload, SI_SUB_DTRACE_PROVIDER, SI_ORDER_ANY, sdt_unload, NULL);
 DEV_MODULE(sdt, sdt_modevent, NULL);
 MODULE_VERSION(sdt, 1);
 MODULE_DEPEND(sdt, dtrace, 1, 1, 1);
+MODULE_DEPEND(sdt, opensolaris, 1, 1, 1);
diff --git a/sys/kern/kern_sdt.c b/sys/kern/kern_sdt.c
index b7213d2051fc..9704326299e6 100644
--- a/sys/kern/kern_sdt.c
+++ b/sys/kern/kern_sdt.c
@@ -28,6 +28,7 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kdb.h>
+#include <sys/proc.h>
 #include <sys/sdt.h>
 
 SDT_PROVIDER_DEFINE(sdt);
@@ -37,7 +38,6 @@ SDT_PROVIDER_DEFINE(sdt);
  * dtrace_probe() when it loads.
  */
 sdt_probe_func_t sdt_probe_func = sdt_probe_stub;
-sdt_probe6_func_t sdt_probe6_func = (sdt_probe6_func_t)sdt_probe_stub;
 volatile bool __read_frequently sdt_probes_enabled;
 
 /*
@@ -48,7 +48,7 @@ volatile bool __read_frequently sdt_probes_enabled;
 void
 sdt_probe_stub(uint32_t id __unused, uintptr_t arg0 __unused,
     uintptr_t arg1 __unused, uintptr_t arg2 __unused, uintptr_t arg3 __unused,
-    uintptr_t arg4 __unused)
+    uintptr_t arg4 __unused, uintptr_t arg5 __unused)
 {
 	printf("sdt_probe_stub: unexpectedly called\n");
 	kdb_backtrace();
@@ -58,12 +58,12 @@ void
 sdt_probe(uint32_t id, uintptr_t arg0, uintptr_t arg1,
     uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
 {
-	sdt_probe_func(id, arg0, arg1, arg2, arg3, arg4);
+	sdt_probe_func(id, arg0, arg1, arg2, arg3, arg4, 0);
 }
 
 void
 sdt_probe6(uint32_t id, uintptr_t arg0, uintptr_t arg1,
     uintptr_t arg2, uintptr_t arg3, uintptr_t arg4, uintptr_t arg5)
 {
-	sdt_probe6_func(id, arg0, arg1, arg2, arg3, arg4, arg5);
+	sdt_probe_func(id, arg0, arg1, arg2, arg3, arg4, arg5);
 }
diff --git a/sys/sys/sdt.h b/sys/sys/sdt.h
index 147d58c53ef4..0987f1cc19c3 100644
--- a/sys/sys/sdt.h
+++ b/sys/sys/sdt.h
@@ -419,15 +419,12 @@ __sdt_probe##uniq:;							\
  * way to avoid having to rely on CDDL code.
  */
 typedef	void (*sdt_probe_func_t)(uint32_t, uintptr_t arg0, uintptr_t arg1,
-    uintptr_t arg2, uintptr_t arg3, uintptr_t arg4);
-typedef	void (*sdt_probe6_func_t)(uint32_t, uintptr_t arg0, uintptr_t arg1,
     uintptr_t arg2, uintptr_t arg3, uintptr_t arg4, uintptr_t arg5);
 
 /*
  * The 'sdt' provider will set it to dtrace_probe when it loads.
  */
 extern sdt_probe_func_t		sdt_probe_func;
-extern sdt_probe6_func_t	sdt_probe6_func;
 
 struct sdt_probe;
 struct sdt_provider;
@@ -466,7 +463,7 @@ struct sdt_provider {
 };
 
 void sdt_probe_stub(uint32_t, uintptr_t, uintptr_t, uintptr_t, uintptr_t,
-    uintptr_t);
+    uintptr_t, uintptr_t);
 
 SDT_PROVIDER_DECLARE(sdt);