diff --git a/lib/libthr/arch/amd64/include/pthread_md.h b/lib/libthr/arch/amd64/include/pthread_md.h
index 0ebea2e..4650222 100644
--- a/lib/libthr/arch/amd64/include/pthread_md.h
+++ b/lib/libthr/arch/amd64/include/pthread_md.h
@@ -49,6 +49,7 @@ struct tcb {
 	struct tcb		*tcb_self;	/* required by rtld */
 	void			*tcb_dtv;	/* required by rtld */
 	struct pthread		*tcb_thread;
+	char			 tcb_dtrace_scratch[64];
 	void			*tcb_spare[1];
 };
 
diff --git a/libexec/rtld-elf/malloc.c b/libexec/rtld-elf/malloc.c
index 8e34362..f10a794 100644
--- a/libexec/rtld-elf/malloc.c
+++ b/libexec/rtld-elf/malloc.c
@@ -490,7 +490,7 @@ int	n;
 	offset = (long)pagepool_start - ((long)pagepool_start & ~(pagesz - 1));
 
 	if ((pagepool_start = mmap(0, n * pagesz,
-			PROT_READ|PROT_WRITE,
+			PROT_READ|PROT_WRITE|PROT_EXEC,
 			MAP_ANON|MAP_COPY, fd, 0)) == (caddr_t)-1) {
 		rtld_printf("Cannot map anonymous memory\n");
 		return 0;
diff --git a/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c b/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c
index 53ad33b..6c51d43 100644
--- a/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c
+++ b/sys/cddl/contrib/opensolaris/uts/intel/dtrace/fasttrap_isa.c
@@ -1571,9 +1571,9 @@ fasttrap_pid_probe(struct reg *rp)
 #ifdef __i386__
 		addr = USD_GETBASE(&curthread->td_pcb->pcb_gsd);
 #else
-		addr = curthread->td_pcb->pcb_gsbase;
+		addr = curthread->td_pcb->pcb_fsbase;
+		addr += sizeof (void *) * 3;
 #endif
-		addr += sizeof (void *);
 
 		/*
 		 * Generic Instruction Tracing