Index: sys/kern/kern_cpuset.c
===================================================================
--- sys/kern/kern_cpuset.c
+++ sys/kern/kern_cpuset.c
@@ -462,6 +462,8 @@
 		return (0);
 	}
 	case CPU_WHICH_IRQ:
+	case CPU_WHICH_INTRHANDLER:
+	case CPU_WHICH_ITHREAD:
 	case CPU_WHICH_DOMAIN:
 		return (0);
 	default:
Index: sys/kern/kern_intr.c
===================================================================
--- sys/kern/kern_intr.c
+++ sys/kern/kern_intr.c
@@ -439,6 +439,7 @@
 	struct thread *td;
 	struct proc *p;
 	cpuset_t *mask;
+	struct cpuset *set;
 	lwpid_t id;
 	int error;
 
@@ -467,12 +468,13 @@
 		} else {
 			id = ie->ie_thread->it_thread->td_tid;
 			mtx_unlock(&ie->ie_lock);
-			error = cpuset_which(CPU_WHICH_TID, id, &p, &td, NULL);
+			error = cpuset_which(CPU_WHICH_TID, id, &p, &td, &set);
 			if (error != 0)
 				return (error);
 			CPU_COPY(&td->td_cpuset->cs_mask, mask);
 			PROC_UNLOCK(p);
 		}
+		break;
 	default:
 		return (EINVAL);
 	}
Index: usr.bin/cpuset/cpuset.1
===================================================================
--- usr.bin/cpuset/cpuset.1
+++ usr.bin/cpuset/cpuset.1
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 29, 2016
+.Dd July 7, 2017
 .Dt CPUSET 1
 .Os
 .Sh NAME
@@ -48,11 +48,11 @@
 .Nm
 .Op Fl c
 .Op Fl l Ar cpu-list
-.Op Fl j Ar jailid | Fl p Ar pid | Fl t Ar tid | Fl s Ar setid | Fl x Ar irq
+.Op Fl j Ar jailid | Fl p Ar pid | Fl t Ar tid | Fl s Ar setid | Fl IXx Ar irq
 .Nm
 .Fl g
 .Op Fl cir
-.Op Fl d Ar domain | Fl j Ar jailid | Fl p Ar pid | Fl t Ar tid | Fl s Ar setid | Fl x Ar irq
+.Op Fl d Ar domain | Fl j Ar jailid | Fl p Ar pid | Fl t Ar tid | Fl s Ar setid | Fl IXx Ar irq
 .Sh DESCRIPTION
 The
 .Nm
@@ -140,7 +140,11 @@
 .It Fl t Ar tid
 Specifies a thread id as the target of the operation.
 .It Fl x Ar irq
-Specifies an irq as the target of the operation.
+Specifies an irq (and ithread) as the target of the operation.
+.It Fl X Ar irq
+Specifies an irq (but not ithread) as the target of the operation.
+.It Fl I Ar irq
+Specifies an ithread (but not irq) as the target of the operation.
 .El
 .Sh EXIT STATUS
 .Ex -std
Index: usr.bin/cpuset/cpuset.c
===================================================================
--- usr.bin/cpuset/cpuset.c
+++ usr.bin/cpuset/cpuset.c
@@ -208,7 +208,7 @@
 	level = CPU_LEVEL_WHICH;
 	which = CPU_WHICH_PID;
 	id = pid = tid = setid = -1;
-	while ((ch = getopt(argc, argv, "Ccd:gij:l:p:rs:t:x:")) != -1) {
+	while ((ch = getopt(argc, argv, "Ccd:gij:l:p:rs:t:x:X:I:")) != -1) {
 		switch (ch) {
 		case 'C':
 			Cflag = 1;
@@ -261,6 +261,16 @@
 			which = CPU_WHICH_IRQ;
 			id = atoi(optarg);
 			break;
+		case 'X':
+			xflag = 1;
+			which = CPU_WHICH_INTRHANDLER;
+			id = atoi(optarg);
+			break;
+		case 'I':
+			xflag = 1;
+			which = CPU_WHICH_ITHREAD;
+			id = atoi(optarg);
+			break;
 		default:
 			usage();
 		}
@@ -357,9 +367,10 @@
 	fprintf(stderr,
 	    "       cpuset [-c] [-l cpu-list] -C -p pid\n");
 	fprintf(stderr,
-	    "       cpuset [-c] [-l cpu-list] [-j jailid | -p pid | -t tid | -s setid | -x irq]\n");
+	    "       cpuset [-c] [-l cpu-list] [-j jailid | -p pid | -t tid | -s setid |\n"
+	    "              -IXx irq]\n");
 	fprintf(stderr,
 	    "       cpuset -g [-cir] [-d domain | -j jailid | -p pid | -t tid | -s setid |\n"
-	    "              -x irq]\n");
+	    "              -IXx irq]\n");
 	exit(1);
 }