diff --git a/tools/ocaml/libs/xc/xenctrl_stubs.c b/tools/ocaml/libs/xc/xenctrl_stubs.c
index c78191f95abc..20487b21008f 100644
--- a/tools/ocaml/libs/xc/xenctrl_stubs.c
+++ b/tools/ocaml/libs/xc/xenctrl_stubs.c
@@ -312,7 +312,10 @@ CAMLprim value stub_xc_domain_max_vcpus(value xch_val, value domid,
 	xc_interface *xch = xch_of_val(xch_val);
 	int r;
 
+	caml_enter_blocking_section();
 	r = xc_domain_max_vcpus(xch, Int_val(domid), Int_val(max_vcpus));
+	caml_leave_blocking_section();
+
 	if (r)
 		failwith_xc(xch);
 
@@ -329,7 +332,10 @@ value stub_xc_domain_sethandle(value xch_val, value domid, value handle)
 
 	domain_handle_of_uuid_string(h, String_val(handle));
 
+	caml_enter_blocking_section();
 	i = xc_domain_sethandle(xch, Int_val(domid), h);
+	caml_leave_blocking_section();
+
 	if (i)
 		failwith_xc(xch);
 
@@ -391,7 +397,10 @@ CAMLprim value stub_xc_domain_shutdown(value xch_val, value domid, value reason)
 	xc_interface *xch = xch_of_val(xch_val);
 	int ret;
 
+	caml_enter_blocking_section();
 	ret = xc_domain_shutdown(xch, Int_val(domid), Int_val(reason));
+	caml_leave_blocking_section();
+
 	if (ret < 0)
 		failwith_xc(xch);
 
@@ -503,7 +512,10 @@ CAMLprim value stub_xc_domain_getinfo(value xch_val, value domid)
 	xc_domaininfo_t info;
 	int ret;
 
+	caml_enter_blocking_section();
 	ret = xc_domain_getinfo_single(xch, Int_val(domid), &info);
+	caml_leave_blocking_section();
+
 	if (ret < 0)
 		failwith_xc(xch);
 
@@ -546,7 +558,10 @@ CAMLprim value stub_xc_vcpu_context_get(value xch_val, value domid,
 	int ret;
 	vcpu_guest_context_any_t ctxt;
 
+	caml_enter_blocking_section();
 	ret = xc_vcpu_getcontext(xch, Int_val(domid), Int_val(cpu), &ctxt);
+	caml_leave_blocking_section();
+
 	if ( ret < 0 )
 		failwith_xc(xch);
 
@@ -584,10 +599,14 @@ CAMLprim value stub_xc_vcpu_setaffinity(value xch_val, value domid,
 		if (Bool_val(Field(cpumap, i)))
 			c_cpumap[i/8] |= 1 << (i&7);
 	}
+
+	caml_enter_blocking_section();
 	retval = xc_vcpu_setaffinity(xch, Int_val(domid),
 				     Int_val(vcpu),
 				     c_cpumap, NULL,
 				     XEN_VCPUAFFINITY_HARD);
+	caml_leave_blocking_section();
+
 	free(c_cpumap);
 
 	if (retval < 0)
@@ -612,10 +631,13 @@ CAMLprim value stub_xc_vcpu_getaffinity(value xch_val, value domid,
 	if (c_cpumap == NULL)
 		failwith_xc(xch);
 
+	caml_enter_blocking_section();
 	retval = xc_vcpu_getaffinity(xch, Int_val(domid),
 				     Int_val(vcpu),
 				     c_cpumap, NULL,
 				     XEN_VCPUAFFINITY_HARD);
+	caml_leave_blocking_section();
+
 	if (retval < 0) {
 		free(c_cpumap);
 		failwith_xc(xch);
@@ -639,9 +661,13 @@ CAMLprim value stub_xc_sched_id(value xch_val)
 {
 	CAMLparam1(xch_val);
 	xc_interface *xch = xch_of_val(xch_val);
-	int sched_id;
+	int ret, sched_id;
+
+	caml_enter_blocking_section();
+	ret = xc_sched_id(xch, &sched_id);
+	caml_leave_blocking_section();
 
-	if (xc_sched_id(xch, &sched_id))
+	if (ret)
 		failwith_xc(xch);
 
 	CAMLreturn(Val_int(sched_id));
@@ -674,7 +700,10 @@ CAMLprim value stub_xc_evtchn_reset(value xch_val, value domid)
 	xc_interface *xch = xch_of_val(xch_val);
 	int r;
 
+	caml_enter_blocking_section();
 	r = xc_evtchn_reset(xch, Int_val(domid));
+	caml_leave_blocking_section();
+
 	if (r < 0)
 		failwith_xc(xch);
 	CAMLreturn(Val_unit);
@@ -811,7 +840,10 @@ CAMLprim value stub_xc_send_debug_keys(value xch_val, value keys)
 	xc_interface *xch = xch_of_val(xch_val);
 	int r;
 
+	caml_enter_blocking_section();
 	r = xc_send_debug_keys(xch, String_val(keys));
+	caml_leave_blocking_section();
+
 	if (r)
 		failwith_xc(xch);
 	CAMLreturn(Val_unit);
@@ -952,7 +984,11 @@ CAMLprim value stub_xc_domain_set_memmap_limit(value xch_val, value domid,
 	int retval;
 
 	v = Int64_val(map_limitkb);
+
+	caml_enter_blocking_section();
 	retval = xc_domain_set_memmap_limit(xch, Int_val(domid), v);
+	caml_leave_blocking_section();
+
 	if (retval)
 		failwith_xc(xch);
 
@@ -1203,8 +1239,11 @@ CAMLprim value stub_xc_domain_ioport_permission(value xch_val, value domid,
 	c_nr_ports = Int_val(nr_ports);
 	c_allow = Bool_val(allow);
 
+	caml_enter_blocking_section();
 	ret = xc_domain_ioport_permission(xch, Int_val(domid),
 					 c_start_port, c_nr_ports, c_allow);
+	caml_leave_blocking_section();
+
 	if (ret < 0)
 		failwith_xc(xch);
 
@@ -1225,8 +1264,11 @@ CAMLprim value stub_xc_domain_iomem_permission(value xch_val, value domid,
 	c_nr_pfns = Nativeint_val(nr_pfns);
 	c_allow = Bool_val(allow);
 
+	caml_enter_blocking_section();
 	ret = xc_domain_iomem_permission(xch, Int_val(domid),
 					 c_start_pfn, c_nr_pfns, c_allow);
+	caml_leave_blocking_section();
+
 	if (ret < 0)
 		failwith_xc(xch);
 
@@ -1245,8 +1287,11 @@ CAMLprim value stub_xc_domain_irq_permission(value xch_val, value domid,
 	c_pirq = Int_val(pirq);
 	c_allow = Bool_val(allow);
 
+	caml_enter_blocking_section();
 	ret = xc_domain_irq_permission(xch, Int_val(domid),
 				       c_pirq, c_allow);
+	caml_leave_blocking_section();
+
 	if (ret < 0)
 		failwith_xc(xch);
 
@@ -1309,7 +1354,9 @@ CAMLprim value stub_xc_domain_test_assign_device(value xch_val, value domid, val
 	func = Int_val(Field(desc, 3));
 	sbdf = encode_sbdf(domain, bus, dev, func);
 
+	caml_enter_blocking_section();
 	ret = xc_test_assign_device(xch, Int_val(domid), sbdf);
+	caml_leave_blocking_section();
 
 	CAMLreturn(Val_bool(ret == 0));
 }
@@ -1328,8 +1375,10 @@ CAMLprim value stub_xc_domain_assign_device(value xch_val, value domid, value de
 	func = Int_val(Field(desc, 3));
 	sbdf = encode_sbdf(domain, bus, dev, func);
 
+	caml_enter_blocking_section();
 	ret = xc_assign_device(xch, Int_val(domid), sbdf,
 			       XEN_DOMCTL_DEV_RDM_RELAXED);
+	caml_leave_blocking_section();
 
 	if (ret < 0)
 		failwith_xc(xch);
@@ -1350,7 +1399,9 @@ CAMLprim value stub_xc_domain_deassign_device(value xch_val, value domid, value
 	func = Int_val(Field(desc, 3));
 	sbdf = encode_sbdf(domain, bus, dev, func);
 
+	caml_enter_blocking_section();
 	ret = xc_deassign_device(xch, Int_val(domid), sbdf);
+	caml_leave_blocking_section();
 
 	if (ret < 0)
 		failwith_xc(xch);
@@ -1379,8 +1430,11 @@ CAMLprim value stub_xc_get_cpu_featureset(value xch_val, value idx)
 		/* To/from hypervisor to retrieve actual featureset */
 		uint32_t fs[fs_len], len = fs_len;
 		unsigned int i;
+		int ret;
 
-		int ret = xc_get_cpu_featureset(xch, Int_val(idx), &len, fs);
+		caml_enter_blocking_section();
+		ret = xc_get_cpu_featureset(xch, Int_val(idx), &len, fs);
+		caml_leave_blocking_section();
 
 		if (ret)
 			failwith_xc(xch);
@@ -1403,7 +1457,10 @@ CAMLprim value stub_xc_watchdog(value xch_val, value domid, value timeout)
 	int ret;
 	unsigned int c_timeout = Int32_val(timeout);
 
+	caml_enter_blocking_section();
 	ret = xc_watchdog(xch, Int_val(domid), c_timeout);
+	caml_leave_blocking_section();
+
 	if (ret < 0)
 		failwith_xc(xch);
 
