Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=664059 This is the version3 patch for BZ#664059. Reattaching pci device back to host without destroying guest or detaching device from guest would cause host to crash. This patch adds a check before doing device reattach. If the device is being assigned to guest, libvirt refuses to reattach device to host. The patch only works for Xen, for it just checks xenstore to get pci device information. This version fixes some formatting problem and moves lock-unlock out of loop so that the check is atomic. Signed-off-by: Yufang Zhang <yuzhang(a)redhat.com&gt; --- src/xen/xen_driver.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 67 insertions(+), 0 deletions(-) diff --git a/src/xen/xen_driver.c b/src/xen/xen_driver.c index 2a07b7b..dd94fbc 100644 --- a/src/xen/xen_driver.c +++ b/src/xen/xen_driver.c @@ -1927,11 +1927,70 @@ out: } static int +xenUnifiedNodeDeviceAssignedDomainId (virNodeDevicePtr dev) +{ + int numdomains; + int ret = -1, i; + int *ids = NULL; + char *bdf = NULL; + char *xref = NULL; + unsigned int domain, bus, slot, function; + virConnectPtr conn = dev->conn; + xenUnifiedPrivatePtr priv = conn->privateData; + + /* Get active domains */ + numdomains = xenUnifiedNumOfDomains(conn); + if (numdomains < 0) { + return ret; + } + if (numdomains > 0){ + if (VIR_ALLOC_N(ids, numdomains) < 0) { + virReportOOMError(); + goto out; + } + if ((numdomains = xenUnifiedListDomains(conn, &ids[0], numdomains)) < 0) { + goto out; + } + } + + /* Get pci bdf */ + if (xenUnifiedNodeDeviceGetPciInfo(dev, &domain, &bus, &slot, &function) < 0) + goto out; + + if (virAsprintf(&bdf, "%04x:%02x:%02x.%0x", + domain, bus, slot, function) < 0) { + virReportOOMError(); + goto out; + } + + xenUnifiedLock(priv); + /* Check if bdf is assigned to one of active domains */ + for (i = 0; i < numdomains; i++ ) { + xref = xenStoreDomainGetPCIID(conn, ids[i], bdf); + if (xref == NULL) { + continue; + } else { + ret = ids[i]; + break; + } + } + xenUnifiedUnlock(priv); + + VIR_FREE(xref); + VIR_FREE(bdf); +out: + VIR_FREE(ids); + + return ret; +} + +static int xenUnifiedNodeDeviceReAttach (virNodeDevicePtr dev) { pciDevice *pci; unsigned domain, bus, slot, function; int ret = -1; + int domid; if (xenUnifiedNodeDeviceGetPciInfo(dev, &domain, &bus, &slot, &function) < 0) return -1; @@ -1940,6 +1999,14 @@ xenUnifiedNodeDeviceReAttach (virNodeDevicePtr dev) if (!pci) return -1; + /* Check if device is assigned to an active guest */ + if ((domid = xenUnifiedNodeDeviceAssignedDomainId(dev)) >= 0) { + xenUnifiedError(VIR_ERR_INTERNAL_ERROR, + _("Device %s has been assigned to guest %d"), + dev->name, domid); + goto out; + } + if (pciReAttachDevice(pci, NULL) < 0) goto out; -- 1.7.4