[libvirt] [PATCH 3/3] qemu: Forbid user aliases for USB controllers

[Michal Privoznik]

https://bugzilla.redhat.com/show_bug.cgi?id=1552127

These are bit different than other devices. Their alias also
specify the name of the bus. For instance, if there are these
'joined' USB devices:

  <controller type='usb' index='0' model='ich9-ehci1'>
    <alias name='ua-myUSB'/>
    <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x7'/>
  </controller>
  <controller type='usb' index='0' model='ich9-uhci1'>
    <master startport='0'/>
    <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0' multifunction='on'/>
  </controller>

which translates to cmd line as:

  -device ich9-usb-ehci1,id=ua-myUSB,bus=pci.0,addr=0x4.0x7
  -device ich9-usb-uhci1,masterbus=usb.0,firstport=0,bus=pci.0,multifunction=on,addr=0x4

The problem is that UHCI is still trying to serve 'usb.0' bus.
Rather than trying to come up with some complicated algorithm to
make everything work, lets forbid user aliases for USB
controllers.

Signed-off-by: Michal Privoznik <mprivozn at redhat.com>
---
 src/qemu/qemu_domain.c                      | 20 +++++++++++++++++++-
 tests/qemuxml2argvdata/user-aliases-usb.xml | 19 +++++++++++++++++++
 tests/qemuxml2argvdata/user-aliases.xml     |  1 -
 tests/qemuxml2argvtest.c                    |  1 +
 4 files changed, 39 insertions(+), 2 deletions(-)
 create mode 100644 tests/qemuxml2argvdata/user-aliases-usb.xml

diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index b55013de6..67c145493 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -4565,6 +4565,21 @@ qemuDomainDeviceDefValidateControllerSATA(const virDomainControllerDef *controll
 }
 
 
+static int
+qemuDomainDeviceDefValidateControllerUSB(const virDomainControllerDef *controller)
+{
+    if (controller->info.alias &&
+        virDomainDeviceAliasIsUserAlias(controller->info.alias)) {
+        virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
+                       _("Providing user alias to USB "
+                         "controllers is not supported yet"));
+        return -1;
+    }
+
+    return 0;
+}
+
+
 static int
 qemuDomainDeviceDefValidateController(const virDomainControllerDef *controller,
                                       const virDomainDef *def,
@@ -4602,10 +4617,13 @@ qemuDomainDeviceDefValidateController(const virDomainControllerDef *controller,
                                                         qemuCaps);
         break;
 
+    case VIR_DOMAIN_CONTROLLER_TYPE_USB:
+        ret = qemuDomainDeviceDefValidateControllerUSB(controller);
+        break;
+
     case VIR_DOMAIN_CONTROLLER_TYPE_FDC:
     case VIR_DOMAIN_CONTROLLER_TYPE_VIRTIO_SERIAL:
     case VIR_DOMAIN_CONTROLLER_TYPE_CCID:
-    case VIR_DOMAIN_CONTROLLER_TYPE_USB:
     case VIR_DOMAIN_CONTROLLER_TYPE_LAST:
         break;
     }
diff --git a/tests/qemuxml2argvdata/user-aliases-usb.xml b/tests/qemuxml2argvdata/user-aliases-usb.xml
new file mode 100644
index 000000000..6dade4572
--- /dev/null
+++ b/tests/qemuxml2argvdata/user-aliases-usb.xml
@@ -0,0 +1,19 @@
+<domain type='kvm'>
+  <name>gentoo</name>
+  <uuid>a75aca4b-a02f-2bcb-4a91-c93cd848c34b</uuid>
+  <memory unit='KiB'>4194304</memory>
+  <currentMemory unit='KiB'>4194304</currentMemory>
+  <vcpu placement='static'>4</vcpu>
+  <os>
+    <type arch='x86_64' machine='pc-i440fx-1.4'>hvm</type>
+    <boot dev='hd'/>
+    <boot dev='cdrom'/>
+  </os>
+  <devices>
+    <emulator>/usr/bin/qemu-system-x86_64</emulator>
+    <controller type='usb' index='0'>
+      <alias name='ua-SomeWeirdController'/>
+      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+    </controller>
+  </devices>
+</domain>
diff --git a/tests/qemuxml2argvdata/user-aliases.xml b/tests/qemuxml2argvdata/user-aliases.xml
index 52132a82d..6f1fed636 100644
--- a/tests/qemuxml2argvdata/user-aliases.xml
+++ b/tests/qemuxml2argvdata/user-aliases.xml
@@ -71,7 +71,6 @@
       <address type='drive' controller='0' bus='1' target='0' unit='0'/>
     </disk>
     <controller type='usb' index='0'>
-      <alias name='ua-SomeWeirdController'/>
       <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
     </controller>
     <controller type='pci' index='0' model='pci-root'>
diff --git a/tests/qemuxml2argvtest.c b/tests/qemuxml2argvtest.c
index 688846b9b..5758811b8 100644
--- a/tests/qemuxml2argvtest.c
+++ b/tests/qemuxml2argvtest.c
@@ -2965,6 +2965,7 @@ mymain(void)
             QEMU_CAPS_DEVICE_ISA_SERIAL,
             QEMU_CAPS_HDA_DUPLEX);
     DO_TEST("user-aliases2", QEMU_CAPS_DEVICE_IOH3420, QEMU_CAPS_ICH9_AHCI);
+    DO_TEST_PARSE_ERROR("user-aliases-usb", QEMU_CAPS_KVM);
 
     if (getenv("LIBVIRT_SKIP_CLEANUP") == NULL)
         virFileDeleteTree(fakerootdir);
-- 
2.16.1