diff --git a/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h b/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h
--- a/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h
+++ b/sys/cddl/contrib/opensolaris/uts/common/sys/dtrace.h
@@ -2399,8 +2399,8 @@
 extern int dtrace_mach_aframes(void);
 
 #if defined(__i386) || defined(__amd64)
-extern int dtrace_instr_size(uchar_t *instr);
-extern int dtrace_instr_size_isa(uchar_t *, model_t, int *);
+extern int dtrace_instr_size(uint8_t *instr);
+extern int dtrace_instr_size_isa(uint8_t *, model_t, int *);
 extern void dtrace_invop_callsite(void);
 #endif
 extern void dtrace_invop_add(int (*)(uintptr_t, struct trapframe *, uintptr_t));
diff --git a/sys/cddl/dev/dtrace/amd64/dtrace_subr.c b/sys/cddl/dev/dtrace/amd64/dtrace_subr.c
--- a/sys/cddl/dev/dtrace/amd64/dtrace_subr.c
+++ b/sys/cddl/dev/dtrace/amd64/dtrace_subr.c
@@ -449,7 +449,7 @@
 			 * Offset the instruction pointer to the instruction
 			 * following the one causing the fault.
 			 */
-			frame->tf_rip += dtrace_instr_size((u_char *) frame->tf_rip);
+			frame->tf_rip += dtrace_instr_size((uint8_t *) frame->tf_rip);
 			return (1);
 		/* Page fault. */
 		case T_PAGEFLT:
@@ -461,7 +461,7 @@
 			 * Offset the instruction pointer to the instruction
 			 * following the one causing the fault.
 			 */
-			frame->tf_rip += dtrace_instr_size((u_char *) frame->tf_rip);
+			frame->tf_rip += dtrace_instr_size((uint8_t *) frame->tf_rip);
 			return (1);
 		default:
 			/* Handle all other traps in the usual way. */
diff --git a/sys/cddl/dev/dtrace/i386/dtrace_subr.c b/sys/cddl/dev/dtrace/i386/dtrace_subr.c
--- a/sys/cddl/dev/dtrace/i386/dtrace_subr.c
+++ b/sys/cddl/dev/dtrace/i386/dtrace_subr.c
@@ -449,7 +449,7 @@
 			 * Offset the instruction pointer to the instruction
 			 * following the one causing the fault.
 			 */
-			frame->tf_eip += dtrace_instr_size((u_char *) frame->tf_eip);
+			frame->tf_eip += dtrace_instr_size((uint8_t *) frame->tf_eip);
 			return (1);
 		/* Page fault. */
 		case T_PAGEFLT:
@@ -461,7 +461,7 @@
 			 * Offset the instruction pointer to the instruction
 			 * following the one causing the fault.
 			 */
-			frame->tf_eip += dtrace_instr_size((u_char *) frame->tf_eip);
+			frame->tf_eip += dtrace_instr_size((uint8_t *) frame->tf_eip);
 			return (1);
 		default:
 			/* Handle all other traps in the usual way. */
diff --git a/sys/cddl/dev/dtrace/x86/instr_size.c b/sys/cddl/dev/dtrace/x86/instr_size.c
--- a/sys/cddl/dev/dtrace/x86/instr_size.c
+++ b/sys/cddl/dev/dtrace/x86/instr_size.c
@@ -49,8 +49,8 @@
 
 typedef	u_int			model_t;
 #define	DATAMODEL_NATIVE	0
-int dtrace_instr_size(uchar_t *);
-int dtrace_instr_size_isa(uchar_t *, model_t, int *);
+int dtrace_instr_size(uint8_t *);
+int dtrace_instr_size_isa(uint8_t *, model_t, int *);
 #endif
 
 #include <dis_tables.h>
@@ -83,7 +83,7 @@
 dtrace_dis_get_byte(void *p)
 {
 	int ret;
-	uchar_t **instr = p;
+	uint8_t **instr = p;
 
 	ret = **instr;
 	*instr += 1;
@@ -101,7 +101,7 @@
  */
 /* ARGSUSED2 */
 static int
-dtrace_dis_isize(uchar_t *instr, dis_isize_t which, model_t model, int *rmindex)
+dtrace_dis_isize(uint8_t *instr, dis_isize_t which, model_t model, int *rmindex)
 {
 	int sz;
 	dis86_t	x;
@@ -127,13 +127,13 @@
 }
 
 int
-dtrace_instr_size_isa(uchar_t *instr, model_t model, int *rmindex)
+dtrace_instr_size_isa(uint8_t *instr, model_t model, int *rmindex)
 {
 	return (dtrace_dis_isize(instr, DIS_ISIZE_INSTR, model, rmindex));
 }
 
 int
-dtrace_instr_size(uchar_t *instr)
+dtrace_instr_size(uint8_t *instr)
 {
 	return (dtrace_dis_isize(instr, DIS_ISIZE_INSTR, DATAMODEL_NATIVE,
 	    NULL));