[PATCH 3/3] qemuDomainDetachDeviceLive: Handle hostevs with unassigned type of address

[Michal Privoznik]

A <hostdev/> can have <address type='unassigned'/> which means
libvirt manages the device detach from/reattach to the host but
the device is never exposed to the guest. This means that we have
to take a shortcut during hotunplug (e.g. never ask QEMU on the
monitor to detach the device, or never wait for DEVICE_DELETED
event).

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_hotplug.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index b998b51f5a..bde5f683d8 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -6043,6 +6043,7 @@ qemuDomainDetachDeviceLive(virDomainObj *vm,
 {
     virDomainDeviceDef detach = { .type = match->type };
     virDomainDeviceInfo *info = NULL;
+    bool unassigned = false;
     int ret = -1;
 
     switch ((virDomainDeviceType)match->type) {
@@ -6181,6 +6182,8 @@ qemuDomainDetachDeviceLive(virDomainObj *vm,
         return -1;
     }
 
+    unassigned = info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_UNASSIGNED;
+
     if (qemuIsMultiFunctionDevice(vm->def, info)) {
         virReportError(VIR_ERR_OPERATION_FAILED,
                        _("cannot hot unplug %s device with multifunction PCI guest address: "
@@ -6225,8 +6228,10 @@ qemuDomainDetachDeviceLive(virDomainObj *vm,
      * Issue the qemu monitor command to delete the device (based on
      * its alias), and optionally wait a short time in case the
      * DEVICE_DELETED event arrives from qemu right away.
+     * Unassigned devices are not exposed to QEMU, so mimic
+     * !async case.
      */
-    if (!async)
+    if (!async || unassigned)
         qemuDomainMarkDeviceForRemoval(vm, info);
 
     if (qemuDomainDeleteDevice(vm, info->alias) < 0) {
@@ -6235,11 +6240,13 @@ qemuDomainDetachDeviceLive(virDomainObj *vm,
         goto cleanup;
     }
 
-    if (async) {
+    if (async && !unassigned) {
         ret = 0;
     } else {
-        if ((ret = qemuDomainWaitForDeviceRemoval(vm)) == 1)
+        if (unassigned ||
+            (ret = qemuDomainWaitForDeviceRemoval(vm)) == 1) {
             ret = qemuDomainRemoveDevice(driver, vm, &detach);
+        }
     }
 
  cleanup:
-- 
2.34.1