[libvirt] [PATCH 3/3] Ensure that PCI device is reattached to host if hotadd fails

[Daniel P. Berrange]

When an attempt to hotplug a PCI device to a guest fails,
the device was left attached to pci-stub. It is neccessary
to reset the device and then attach it to the host driver
again.

* src/qemu/qemu_driver.c: Reattach PCI device to host if
  hotadd fails
---
 src/qemu/qemu_driver.c |   17 ++++++++++++++++-
 1 files changed, 16 insertions(+), 1 deletions(-)

diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 7ff5542..62b4502 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -7701,6 +7701,7 @@ static int qemudDomainAttachHostPciDevice(struct qemud_driver *driver,
         pciFreeDevice(pci);
         return -1;
     }
+    pci = NULL; /* activePciHostdevs owns the 'pci' reference now */
 
     if (qemuCmdFlags & QEMUD_CMD_FLAG_DEVICE) {
         if (qemuAssignDeviceHostdevAlias(vm->def, hostdev, -1) < 0)
@@ -7768,8 +7769,22 @@ error:
         qemuDomainPCIAddressReleaseAddr(priv->pciaddrs, &hostdev->info) < 0)
         VIR_WARN0("Unable to release PCI address on host device");
 
-    VIR_FREE(devstr);
+    pci = pciGetDevice(hostdev->source.subsys.u.pci.domain,
+                       hostdev->source.subsys.u.pci.bus,
+                       hostdev->source.subsys.u.pci.slot,
+                       hostdev->source.subsys.u.pci.function);
+
     pciDeviceListDel(driver->activePciHostdevs, pci);
+
+    if (pciResetDevice(pci, driver->activePciHostdevs) < 0)
+        VIR_WARN0("Unable to reset PCI device after assign failure");
+    else if (hostdev->managed &&
+             pciReAttachDevice(pci) < 0)
+        VIR_WARN0("Unable to re-attach PCI device after assign failure");
+    pciFreeDevice(pci);
+
+
+    VIR_FREE(devstr);
     VIR_FREE(configfd_name);
     if (configfd >= 0)
         close(configfd);
-- 
1.6.6.1