diff --git a/sys/dev/acpica/acpi.c b/sys/dev/acpica/acpi.c
index 22d2b10ff905..9196c446ae80 100644
--- a/sys/dev/acpica/acpi.c
+++ b/sys/dev/acpica/acpi.c
@@ -1376,11 +1376,9 @@ acpi_reserve_resources(device_t dev)
     struct resource_list_entry *rle;
     struct resource_list *rl;
     struct acpi_device *ad;
-    struct acpi_softc *sc;
     device_t *children;
     int child_count, i;
 
-    sc = device_get_softc(dev);
     if (device_get_children(dev, &children, &child_count) != 0)
 	return;
     for (i = 0; i < child_count; i++) {
@@ -1422,14 +1420,12 @@ acpi_reserve_resources(device_t dev)
 	}
     }
     free(children, M_TEMP);
-    sc->acpi_resources_reserved = 1;
 }
 
 static int
 acpi_set_resource(device_t dev, device_t child, int type, int rid,
     rman_res_t start, rman_res_t count)
 {
-    struct acpi_softc *sc = device_get_softc(dev);
     struct acpi_device *ad = device_get_ivars(child);
     struct resource_list *rl = &ad->ad_rl;
     ACPI_DEVICE_INFO *devinfo;
@@ -1485,38 +1481,6 @@ acpi_set_resource(device_t dev, device_t child, int type, int rid,
     /* Add the resource. */
     end = (start + count - 1);
     resource_list_add(rl, type, rid, start, end, count);
-
-    /* Don't reserve resources until the system resources are allocated. */
-    if (!sc->acpi_resources_reserved)
-	return (0);
-
-    /* Don't reserve system resources. */
-    if (ACPI_ID_PROBE(dev, child, sysres_ids, NULL) <= 0)
-	return (0);
-
-    /*
-     * Don't reserve IRQ resources.  There are many sticky things to
-     * get right otherwise (e.g. IRQs for psm, atkbd, and HPET when
-     * using legacy routing).
-     */
-    if (type == SYS_RES_IRQ)
-	return (0);
-
-    /*
-     * Don't reserve resources for CPU devices.  Some of these
-     * resources need to be allocated as shareable, but reservations
-     * are always non-shareable.
-     */
-    if (device_get_devclass(child) == devclass_find("cpu"))
-	return (0);
-
-    /*
-     * Reserve the resource.
-     *
-     * XXX: Ignores failure for now.  Failure here is probably a
-     * BIOS/firmware bug?
-     */
-    resource_list_reserve(rl, dev, child, type, &rid, start, end, count, 0);
     return (0);
 }
 
diff --git a/sys/dev/acpica/acpi_apei.c b/sys/dev/acpica/acpi_apei.c
index 6a3d9d10edd4..9cfd46c97430 100644
--- a/sys/dev/acpica/acpi_apei.c
+++ b/sys/dev/acpica/acpi_apei.c
@@ -711,7 +711,7 @@ apei_attach(device_t dev)
 		if (ge->v1.Header.Type == ACPI_HEST_TYPE_GENERIC_ERROR_V2) {
 			ge->res2_rid = rid++;
 			acpi_bus_alloc_gas(dev, &ge->res2_type, &ge->res2_rid,
-			    &ge->v2.ReadAckRegister, &ge->res2, 0);
+			    &ge->v2.ReadAckRegister, &ge->res2, RF_SHAREABLE);
 			if (ge->res2 == NULL)
 				device_printf(dev, "Can't allocate ack resource.\n");
 		}
diff --git a/sys/dev/acpica/acpivar.h b/sys/dev/acpica/acpivar.h
index 5be0939ee6bb..4d76a77cdbf8 100644
--- a/sys/dev/acpica/acpivar.h
+++ b/sys/dev/acpica/acpivar.h
@@ -55,7 +55,6 @@ struct acpi_softc {
     int			acpi_enabled;
     int			acpi_sstate;
     int			acpi_sleep_disabled;
-    int			acpi_resources_reserved;
 
     struct sysctl_ctx_list acpi_sysctl_ctx;
     struct sysctl_oid	*acpi_sysctl_tree;