Attempting to start a domain with USB hostdevs but no USB controllers
fails with the rather cryptic error
libxl: error: libxl_qmp.c:287:qmp_handle_error_response: received an
error message from QMP server: Bus 'xenusb-0.0' not found
This can be fixed by creating default USB controllers. When no USB
controllers are defined, create the number of 8 port controllers
necessary to accommodate the number of defined USB devices.
Note that USB controllers are already created as needed in the
domainAttachDevice code path. E.g. a USB controller will be created,
if necessary, when attaching a USB device with
'virsh attach-device dom usbdev.xml'.
Signed-off-by: Jim Fehlig <jfehlig@xxxxxxxx>
---
V1 here
https://www.redhat.com/archives/libvir-list/2017-April/msg00965.html
While further testing of V1 found a libvirtd segfault due to
incorrectly using virDomainControllerInsertPreAlloced instead of
virDomainControllerInsert.
src/libxl/libxl_conf.c | 82 +++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 71 insertions(+), 11 deletions(-)
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
index 56bc09719..cdf6ec9f3 100644
--- a/src/libxl/libxl_conf.c
+++ b/src/libxl/libxl_conf.c
@@ -1822,34 +1822,94 @@ libxlMakeUSBController(virDomainControllerDefPtr controller,
}
static int
+libxlMakeDefaultUSBControllers(virDomainDefPtr def,
+ libxl_domain_config *d_config)
+{
+ virDomainControllerDefPtr l_controller = NULL;
+ libxl_device_usbctrl *x_controllers = NULL;
+ size_t nusbdevs = 0;
+ size_t ncontrollers;
+ size_t i;
+
+ for (i = 0; i < def->nhostdevs; i++) {
+ if (def->hostdevs[i]->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS &&
+ def->hostdevs[i]->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_USB)
+ nusbdevs++;
+ }
+
+ /* No controllers needed if there are no USB devs */
+ if (nusbdevs == 0)
+ return 0;
+
+ /* Create USB controllers with 8 ports */
+ ncontrollers = VIR_DIV_UP(nusbdevs, 8);
+ if (VIR_ALLOC_N(x_controllers, ncontrollers) < 0)
+ return -1;
+
+ for (i = 0; i < ncontrollers; i++) {
+ if (!(l_controller = virDomainControllerDefNew(VIR_DOMAIN_CONTROLLER_TYPE_USB)))
+ goto error;
+
+ l_controller->model = VIR_DOMAIN_CONTROLLER_MODEL_USB_QUSB2;
+ l_controller->idx = i;
+ l_controller->opts.usbopts.ports = 8;
+
+ libxl_device_usbctrl_init(&x_controllers[i]);
+
+ if (libxlMakeUSBController(l_controller, &x_controllers[i]) < 0)
+ goto error;
+
+ if (virDomainControllerInsert(def, l_controller) < 0)
+ goto error;
+
+ l_controller = NULL;
+ }
+
+ d_config->usbctrls = x_controllers;
+ d_config->num_usbctrls = ncontrollers;
+ return 0;
+
+ error:
+ virDomainControllerDefFree(l_controller);
+ for (i = 0; i < ncontrollers; i++)
+ libxl_device_usbctrl_dispose(&x_controllers[i]);
+ VIR_FREE(x_controllers);
+ return -1;
+}
+
+static int
libxlMakeUSBControllerList(virDomainDefPtr def, libxl_domain_config *d_config)
{
virDomainControllerDefPtr *l_controllers = def->controllers;
size_t ncontrollers = def->ncontrollers;
size_t nusbctrls = 0;
libxl_device_usbctrl *x_usbctrls;
- size_t i;
-
- if (ncontrollers == 0)
- return 0;
-
- if (VIR_ALLOC_N(x_usbctrls, ncontrollers) < 0)
- return -1;
+ size_t i, j;
for (i = 0; i < ncontrollers; i++) {
+ if (l_controllers[i]->type == VIR_DOMAIN_CONTROLLER_TYPE_USB)
+ nusbctrls++;
+ }
+
+ if (nusbctrls == 0)
+ return libxlMakeDefaultUSBControllers(def, d_config);
+
+ if (VIR_ALLOC_N(x_usbctrls, nusbctrls) < 0)
+ return -1;
+
+ for (i = 0, j = 0; i < ncontrollers && j < nusbctrls; i++) {
if (l_controllers[i]->type != VIR_DOMAIN_CONTROLLER_TYPE_USB)
continue;
- libxl_device_usbctrl_init(&x_usbctrls[nusbctrls]);
+ libxl_device_usbctrl_init(&x_usbctrls[j]);
if (libxlMakeUSBController(l_controllers[i],
- &x_usbctrls[nusbctrls]) < 0)
+ &x_usbctrls[j]) < 0)
goto error;
- nusbctrls++;
+ j++;
}
- VIR_SHRINK_N(x_usbctrls, ncontrollers, ncontrollers - nusbctrls);
d_config->usbctrls = x_usbctrls;
d_config->num_usbctrls = nusbctrls;
