Index: sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c
===================================================================
--- sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c
+++ sys/cddl/contrib/opensolaris/uts/common/dtrace/dtrace.c
@@ -7291,6 +7291,20 @@
 #endif
 
 	cookie = dtrace_interrupt_disable();
+	/*
+	 * NOTE: This check is not performed if DEBUG is not defined.
+	 *
+	 * Unless this is an ERROR probe, we are not allowed to recurse in
+	 * dtrace_probe(). Recursing into DTrace probe usually means that a
+	 * function is instrumented that should not have been instrumented or
+	 * that the ordering guarantee of the records will be violated,
+	 * resulting in unexpected output. If there is an exception to this
+	 * assertion, a new case should be added.
+	 */
+	ASSERT(curthread->t_dtrace_wouldrecurse == 0 ||
+	    id == dtrace_probeid_error);
+	curthread->t_dtrace_wouldrecurse = 1;
+
 	probe = dtrace_probes[id - 1];
 	cpuid = curcpu;
 	onintr = CPU_ON_INTR(CPU);
@@ -7301,6 +7315,7 @@
 		 * We have hit in the predicate cache; we know that
 		 * this predicate would evaluate to be false.
 		 */
+		curthread->t_dtrace_wouldrecurse = 0;
 		dtrace_interrupt_enable(cookie);
 		return;
 	}
@@ -7313,6 +7328,7 @@
 		/*
 		 * We don't trace anything if we're panicking.
 		 */
+		curthread->t_dtrace_wouldrecurse = 0;
 		dtrace_interrupt_enable(cookie);
 		return;
 	}
@@ -7939,6 +7955,7 @@
 	if (vtime)
 		curthread->t_dtrace_start = dtrace_gethrtime();
 
+	curthread->t_dtrace_wouldrecurse = 0;
 	dtrace_interrupt_enable(cookie);
 }
 
Index: sys/cddl/dev/dtrace/dtrace_cddl.h
===================================================================
--- sys/cddl/dev/dtrace/dtrace_cddl.h
+++ sys/cddl/dev/dtrace/dtrace_cddl.h
@@ -63,15 +63,18 @@
 #ifdef __amd64__
 			u_int8_t	_td_dtrace_reg;
 #endif
+			u_int8_t	_td_dtrace_wouldrecurse;
+					/* Are we recursing dtrace_probe()? */
 		} _tds;
 		u_long	_td_dtrace_ft;	/* Bitwise or of these flags. */
 	} _tdu;
-#define	td_dtrace_ft	_tdu._td_dtrace_ft
-#define	td_dtrace_on	_tdu._tds._td_dtrace_on
-#define	td_dtrace_step	_tdu._tds._td_dtrace_step
-#define	td_dtrace_ret	_tdu._tds._td_dtrace_ret
-#define	td_dtrace_ast	_tdu._tds._td_dtrace_ast
-#define	td_dtrace_reg	_tdu._tds._td_dtrace_reg
+#define	td_dtrace_ft		_tdu._td_dtrace_ft
+#define	td_dtrace_on		_tdu._tds._td_dtrace_on
+#define	td_dtrace_step		_tdu._tds._td_dtrace_step
+#define	td_dtrace_ret		_tdu._tds._td_dtrace_ret
+#define	td_dtrace_ast		_tdu._tds._td_dtrace_ast
+#define	td_dtrace_reg		_tdu._tds._td_dtrace_reg
+#define	td_dtrace_wouldrecurse	_tdu._tds._td_dtrace_wouldrecurse
 
 	uintptr_t	td_dtrace_pc;	/* DTrace saved pc from fasttrap. */
 	uintptr_t	td_dtrace_npc;	/* DTrace next pc from fasttrap. */
@@ -111,6 +114,7 @@
 #define	t_dtrace_regv	td_dtrace->td_dtrace_regv
 #define	t_dtrace_sscr	td_dtrace->td_dtrace_sscr
 #define	t_dtrace_systrace_args	td_dtrace->td_systrace_args
+#define	t_dtrace_wouldrecurse	td_dtrace->td_dtrace_wouldrecurse
 #define	p_dtrace_helpers	p_dtrace->p_dtrace_helpers
 #define	p_dtrace_count	p_dtrace->p_dtrace_count
 #define	p_dtrace_probes	p_dtrace->p_dtrace_probes