Index: sys/arm/arm/machdep.c
===================================================================
--- sys/arm/arm/machdep.c
+++ sys/arm/arm/machdep.c
@@ -550,14 +550,9 @@
 int
 fill_regs(struct thread *td, struct reg *regs)
 {
-	struct trapframe *tf = td->td_frame;
-	bcopy(&tf->tf_r0, regs->r, sizeof(regs->r));
-	regs->r_sp = tf->tf_usr_sp;
-	regs->r_lr = tf->tf_usr_lr;
-	regs->r_pc = tf->tf_pc;
-	regs->r_cpsr = tf->tf_spsr;
-	return (0);
+	return fill_frame_regs(td->td_frame, regs);
 }
+
 int
 fill_fpregs(struct thread *td, struct fpreg *regs)
 {
@@ -566,6 +561,17 @@
 }
 
 int
+fill_frame_regs(struct trapframe *tf, struct reg *regs)
+{
+	bcopy(&tf->tf_r0, regs->r, sizeof(regs->r));
+	regs->r_sp = tf->tf_usr_sp;
+	regs->r_lr = tf->tf_usr_lr;
+	regs->r_pc = tf->tf_pc;
+	regs->r_cpsr = tf->tf_spsr;
+	return (0);
+}
+
+int
 set_regs(struct thread *td, struct reg *regs)
 {
 	struct trapframe *tf = td->td_frame;
Index: sys/arm/arm/undefined.c
===================================================================
--- sys/arm/arm/undefined.c
+++ sys/arm/arm/undefined.c
@@ -86,6 +86,10 @@
 #include <machine/db_machdep.h>
 #endif
 
+#ifdef KDTRACE_HOOKS
+#include <sys/dtrace_bsd.h>
+#endif
+
 #define	ARM_COPROC_INSN(insn)	(((insn) & (1 << 27)) != 0)
 #define	ARM_VFP_INSN(insn)	((((insn) & 0xfe000000) == 0xf2000000) || \
     (((insn) & 0xff100000) == 0xf4000000))
@@ -303,22 +307,39 @@
 		    break;
 
 	if (fault_code & FAULT_USER) {
-		/* TODO: No support for ptrace from Thumb-2 */
-		if ((frame->tf_spsr & PSR_T) == 0 &&
-		    fault_instruction == PTRACE_BREAKPOINT) {
-			PROC_LOCK(td->td_proc);
-			_PHOLD(td->td_proc);
-			error = ptrace_clear_single_step(td);
-			_PRELE(td->td_proc);
-			PROC_UNLOCK(td->td_proc);
-			if (error != 0) {
-				ksiginfo_init_trap(&ksi);
-				ksi.ksi_signo = SIGILL;
-				ksi.ksi_code = ILL_ILLOPC;
-				ksi.ksi_addr = (u_int32_t *)(intptr_t) fault_pc;
-				trapsignal(td, &ksi);
+		/* TODO: No support for Thumb-2 */
+		if ((frame->tf_spsr & PSR_T) == 0) {
+			if (fault_instruction == PTRACE_BREAKPOINT) {
+				PROC_LOCK(td->td_proc);
+				_PHOLD(td->td_proc);
+				error = ptrace_clear_single_step(td);
+				_PRELE(td->td_proc);
+				PROC_UNLOCK(td->td_proc);
+				if (error != 0) {
+					ksiginfo_init_trap(&ksi);
+					ksi.ksi_signo = SIGILL;
+					ksi.ksi_code = ILL_ILLOPC;
+					ksi.ksi_addr = (u_int32_t *)(intptr_t) fault_pc;
+					trapsignal(td, &ksi);
+				}
+				return;
 			}
-			return;
+#ifdef KDTRACE_HOOKS
+			else if (fault_instruction == FASTTRAP_BREAKPOINT) {
+				struct reg regs;
+				fill_frame_regs(frame, &regs);
+				if (dtrace_pid_probe_ptr != NULL &&
+				    dtrace_pid_probe_ptr(&regs) == 0)
+					return;
+			}
+			else if (fault_instruction == FASTTRAPRET_BREAKPOINT) {
+				struct reg regs;
+				fill_frame_regs(frame, &regs);
+				if (dtrace_return_probe_ptr != NULL &&
+				    dtrace_return_probe_ptr(&regs) == 0)
+					return;
+			}
+#endif
 		}
 	}
 
Index: sys/arm/include/reg.h
===================================================================
--- sys/arm/include/reg.h
+++ sys/arm/include/reg.h
@@ -4,6 +4,7 @@
 #define MACHINE_REG_H
 
 #include <machine/fp.h>
+#include <machine/frame.h>
 
 struct reg {
 	unsigned int r[13];
@@ -29,6 +30,7 @@
 int     set_fpregs(struct thread *, struct fpreg *);
 int     fill_dbregs(struct thread *, struct dbreg *);
 int     set_dbregs(struct thread *, struct dbreg *);
+int     fill_frame_regs(struct trapframe *, struct reg *);
 #endif
 
 #endif /* !MACHINE_REG_H */
Index: sys/arm/include/trap.h
===================================================================
--- sys/arm/include/trap.h
+++ sys/arm/include/trap.h
@@ -8,4 +8,6 @@
 #define PTRACE_BREAKPOINT	0xe7fffff0
 #define KERNEL_BREAKPOINT	0xe7ffffff
 #define FBT_BREAKPOINT		0xe7f000f0
+#define	FASTTRAP_BREAKPOINT	0xe7f000f1
+#define	FASTTRAPRET_BREAKPOINT	0xe7f000f2
 #endif /* _MACHINE_TRAP_H_ */
Index: sys/modules/dtrace/Makefile
===================================================================
--- sys/modules/dtrace/Makefile
+++ sys/modules/dtrace/Makefile
@@ -18,13 +18,13 @@
 .if ${MACHINE_CPUARCH} == "amd64"
 SUBDIR+=	systrace_linux32
 .endif
-.if ${MACHINE_CPUARCH} == "powerpc"
+.if ${MACHINE_CPUARCH} == "powerpc" || ${MACHINE_CPUARCH} == "arm"
 SUBDIR+=	fbt fasttrap
 .endif
 .if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_ARCH} == "powerpc64"
 SUBDIR+=	systrace_freebsd32
 .endif
-.if ${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "arm"
+.if ${MACHINE_CPUARCH} == "aarch64"
 SUBDIR+=	fbt
 .endif
 .include <bsd.subdir.mk>
Index: sys/modules/dtrace/dtraceall/dtraceall.c
===================================================================
--- sys/modules/dtrace/dtraceall/dtraceall.c
+++ sys/modules/dtrace/dtraceall/dtraceall.c
@@ -73,7 +73,7 @@
     defined(__i386__) || defined(__powerpc__)
 MODULE_DEPEND(dtraceall, fbt, 1, 1, 1);
 #endif
-#if defined(__amd64__) || defined(__i386__)
+#if defined(__amd64__) || defined(__i386__) || defined(__arm__)
 MODULE_DEPEND(dtraceall, fasttrap, 1, 1, 1);
 #endif
 MODULE_DEPEND(dtraceall, sdt, 1, 1, 1);
Index: sys/modules/dtrace/fasttrap/Makefile
===================================================================
--- sys/modules/dtrace/fasttrap/Makefile
+++ sys/modules/dtrace/fasttrap/Makefile
@@ -15,9 +15,9 @@
 .if ${MACHINE_CPUARCH} == "amd64" ||  ${MACHINE_CPUARCH} == "i386"
 CFLAGS+=	-I${SYSDIR}/cddl/contrib/opensolaris/uts/intel
 .PATH:		${SYSDIR}/cddl/contrib/opensolaris/uts/intel/dtrace
-.elif ${MACHINE_CPUARCH} == "powerpc"
-CFLAGS+=	-I${SYSDIR}/cddl/contrib/opensolaris/uts/powerpc
-.PATH:		${SYSDIR}/cddl/contrib/opensolaris/uts/powerpc/dtrace
+.else
+CFLAGS+=	-I${SYSDIR}/cddl/contrib/opensolaris/uts/${MACHINE_CPUARCH}
+.PATH:		${SYSDIR}/cddl/contrib/opensolaris/uts/${MACHINE_CPUARCH}/dtrace
 .endif
 
 .PATH:		${SYSDIR}/cddl/contrib/opensolaris/common/unicode