diff --git a/ChangeLog b/ChangeLog
index 3bf68fc4c9..5b4a9d09a6 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,24 @@
-Thu Apr  3 11:55:00 BST 2009 Daniel P. Berrange <berrange@redhat.com>
+Fri Apr  3 11:55:00 BST 2009 Daniel P. Berrange <berrange@redhat.com>
+
+	Support PCI passthrough in Xen driver
+	* src/pci.c: Refactor to support Xen's pci-back.ko too
+	* src/xen_unified.c: Implement node device reattach/detach
+	reset APIs
+	* src/xend_internal.c: Handle creation of VMs with PCI
+	devices
+	* src/xm_internal.c: serialization of PCI device config
+	* tests/sexpr2xmltest.c, tests/xmconfigtest.c,
+	tests/xml2sexprtest.c: Add tests for PCI devices
+	* tests/sexpr2xmldata/sexpr2xml-pci-devs.sexpr,
+	tests/sexpr2xmldata/sexpr2xml-pci-devs.xml,
+	tests/xmconfigdata/test-pci-devs.cfg,
+	tests/xmconfigdata/test-pci-devs.xml,
+	tests/xml2sexprdata/xml2sexpr-pci-devs.sexpr,
+	tests/xml2sexprdata/xml2sexpr-pci-devs.xml: Add data
+	files for PCI testing
+
+
+Fri Apr  3 11:55:00 BST 2009 Daniel P. Berrange <berrange@redhat.com>
 
 	Improve error reporting/ verification of security labels
 	(Dan Walsh)
diff --git a/src/pci.c b/src/pci.c
index b197b8efe2..ed64d6881a 100644
--- a/src/pci.c
+++ b/src/pci.c
@@ -614,46 +614,86 @@ pciResetDevice(virConnectPtr conn, pciDevice *dev)
     return ret;
 }
 
-static int
-pciBindDeviceToStub(virConnectPtr conn, pciDevice *dev, const char *stub_module)
+
+static void
+pciDriverDir(char *buf, size_t buflen, const char *driver)
 {
-    char stub_dir[PATH_MAX];
-    char path[PATH_MAX];
+    snprintf(buf, buflen, PCI_SYSFS "drivers/%s", driver);
+}
 
-    snprintf(stub_dir, sizeof(stub_dir), PCI_SYSFS "drivers/%s", stub_module);
+static void
+pciDriverFile(char *buf, size_t buflen, const char *driver, const char *file)
+{
+    snprintf(buf, buflen, PCI_SYSFS "drivers/%s/%s", driver, file);
+}
 
-    /* Try loading the stub module if it isn't already loaded;
-     * Do not return an error if the stub module is not available.
-     */
-    if (!virFileExists(stub_dir)) {
-        const char *const modprobeargv[] = { MODPROBE, stub_module, NULL };
+static void
+pciDeviceFile(char *buf, size_t buflen, const char *device, const char *file)
+{
+    snprintf(buf, buflen, PCI_SYSFS "devices/%s/%s", device, file);
+}
 
-        if (virRun(conn, modprobeargv, NULL) < 0) {
+
+static const char *
+pciFindStubDriver(virConnectPtr conn)
+{
+    char drvpath[PATH_MAX];
+    int probed = 0;
+
+recheck:
+    pciDriverDir(drvpath, sizeof(drvpath), "pci-stub");
+    if (virFileExists(drvpath))
+        return "pci-stub";
+    pciDriverDir(drvpath, sizeof(drvpath), "pciback");
+    if (virFileExists(drvpath))
+        return "pciback";
+
+    if (!probed) {
+        const char *const stubprobe[] = { MODPROBE, "pci-stub", NULL };
+        const char *const backprobe[] = { MODPROBE, "pciback", NULL };
+
+        probed = 1;
+        /*
+         * Probing for pci-stub will succeed regardless of whether
+         * on native or Xen kernels.
+         * On Xen though, we want to prefer pciback, so probe
+         * for that first, because that will only work on Xen
+         */
+        if (virRun(conn, backprobe, NULL) < 0 &&
+            virRun(conn, stubprobe, NULL) < 0) {
             char ebuf[1024];
-            VIR_WARN(_("modprobe %s failed: %s"), stub_module,
+            VIR_WARN(_("failed to load pci-stub or pciback drivers: %s"),
                      virStrerror(errno, ebuf, sizeof ebuf));
+            return 0;
         }
+
+        goto recheck;
     }
 
-    if (!virFileExists(stub_dir)) {
-        VIR_WARN(_("%s module not available, cannot bind device %s to it"),
-                 stub_module, dev->name);
-    } else {
-        /* Add the PCI device ID to the stub's dynamic ID table;
-         * this is needed to allow us to bind the device to the stub.
-         * Note: if the device is not currently bound to any driver,
-         * stub will immediately be bound to the device. Also, note
-         * that if a new device with this ID is hotplugged, or if a probe
-         * is triggered for such a device, it will also be immediately
-         * bound by the stub.
-         */
-        snprintf(path, sizeof(path), "%s/new_id", stub_dir);
-        if (virFileWriteStr(path, dev->id) < 0) {
-            virReportSystemError(conn, errno,
-                                 _("Failed to add PCI device ID '%s' to %s"),
-                                 dev->id, stub_module);
-            return -1;
-        }
+    return NULL;
+}
+
+
+static int
+pciBindDeviceToStub(virConnectPtr conn, pciDevice *dev, const char *driver)
+{
+    char drvdir[PATH_MAX];
+    char path[PATH_MAX];
+
+    /* Add the PCI device ID to the stub's dynamic ID table;
+     * this is needed to allow us to bind the device to the stub.
+     * Note: if the device is not currently bound to any driver,
+     * stub will immediately be bound to the device. Also, note
+     * that if a new device with this ID is hotplugged, or if a probe
+     * is triggered for such a device, it will also be immediately
+     * bound by the stub.
+     */
+    pciDriverFile(path, sizeof(path), driver, "new_id");
+    if (virFileWriteStr(path, dev->id) < 0) {
+        virReportSystemError(conn, errno,
+                             _("Failed to add PCI device ID '%s' to %s"),
+                             dev->id, driver);
+        return -1;
     }
 
     /* If the device is already bound to a driver, unbind it.
@@ -661,38 +701,45 @@ pciBindDeviceToStub(virConnectPtr conn, pciDevice *dev, const char *stub_module)
      * PCI device happens to be IDE controller for the disk hosting
      * your root filesystem.
      */
-    snprintf(path, sizeof(path),
-             PCI_SYSFS "devices/%s/driver/unbind", dev->name);
+    pciDeviceFile(path, sizeof(path), dev->name, "driver/unbind");
     if (virFileExists(path) && virFileWriteStr(path, dev->name) < 0) {
         virReportSystemError(conn, errno,
                              _("Failed to unbind PCI device '%s'"), dev->name);
         return -1;
     }
 
-    if (virFileExists(stub_dir)) {
-        /* If the device isn't already bound to pci-stub, try binding it now.
-         */
-        snprintf(path, sizeof(path), PCI_SYSFS "devices/%s/driver", dev->name);
-        if (!virFileLinkPointsTo(path, stub_dir)) {
-            snprintf(path, sizeof(path), "%s/bind", stub_dir);
-            if (virFileWriteStr(path, dev->name) < 0) {
-                virReportSystemError(conn, errno,
-                                     _("Failed to bind PCI device '%s' to %s"),
-                                     dev->name, stub_module);
-                return -1;
-            }
-        }
-
-        /* If 'remove_id' exists, remove the device id from pci-stub's dynamic
-         * ID table so that 'drivers_probe' works below.
-         */
-        snprintf(path, sizeof(path), "%s/remove_id", stub_dir);
-        if (virFileExists(path) && virFileWriteStr(path, dev->id) < 0) {
+    /* If the device isn't already bound to pci-stub, try binding it now.
+     */
+    pciDriverDir(drvdir, sizeof(drvdir), driver);
+    pciDeviceFile(path, sizeof(path), dev->name, "driver");
+    if (!virFileLinkPointsTo(path, drvdir)) {
+        /* Xen's pciback.ko wants you to use new_slot first */
+        pciDriverFile(path, sizeof(path), driver, "new_slot");
+        if (virFileExists(path) && virFileWriteStr(path, dev->name) < 0) {
             virReportSystemError(conn, errno,
-                                 _("Failed to remove PCI ID '%s' from %s"),
-                                 dev->id, stub_module);
+                                 _("Failed to add slot for PCI device '%s' to %s"),
+                                 dev->name, driver);
             return -1;
         }
+
+        pciDriverFile(path, sizeof(path), driver, "bind");
+        if (virFileWriteStr(path, dev->name) < 0) {
+            virReportSystemError(conn, errno,
+                                 _("Failed to bind PCI device '%s' to %s"),
+                                 dev->name, driver);
+            return -1;
+        }
+    }
+
+    /* If 'remove_id' exists, remove the device id from pci-stub's dynamic
+     * ID table so that 'drivers_probe' works below.
+     */
+    pciDriverFile(path, sizeof(path), driver, "remove_id");
+    if (virFileExists(path) && virFileWriteStr(path, dev->id) < 0) {
+        virReportSystemError(conn, errno,
+                             _("Failed to remove PCI ID '%s' from %s"),
+                             dev->id, driver);
+        return -1;
     }
 
     return 0;
@@ -701,37 +748,53 @@ pciBindDeviceToStub(virConnectPtr conn, pciDevice *dev, const char *stub_module)
 int
 pciDettachDevice(virConnectPtr conn, pciDevice *dev)
 {
-    return pciBindDeviceToStub(conn, dev, "pci-stub");
+    const char *driver = pciFindStubDriver(conn);
+    if (!driver) {
+        pciReportError(conn, VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("cannot find any PCI stub module"));
+        return -1;
+    }
+
+    return pciBindDeviceToStub(conn, dev, driver);
 }
 
 static int
-pciUnBindDeviceFromStub(virConnectPtr conn, pciDevice *dev, const char *stub_module)
+pciUnBindDeviceFromStub(virConnectPtr conn, pciDevice *dev, const char *driver)
 {
-    char stub_dir[PATH_MAX];
+    char drvdir[PATH_MAX];
     char path[PATH_MAX];
 
-    snprintf(stub_dir, sizeof(stub_dir), PCI_SYSFS "drivers/%s", stub_module);
-
     /* If the device is bound to stub, unbind it.
      */
-    snprintf(path, sizeof(path), PCI_SYSFS "devices/%s/driver", dev->name);
-    if (virFileExists(stub_dir) && virFileLinkPointsTo(path, stub_dir)) {
-        snprintf(path, sizeof(path), "%s/unbind", stub_dir);
+    pciDriverDir(drvdir, sizeof(drvdir), driver);
+    pciDeviceFile(path, sizeof(path), dev->name, "driver");
+    if (virFileExists(drvdir) && virFileLinkPointsTo(path, drvdir)) {
+        pciDriverFile(path, sizeof(path), driver, "unbind");
         if (virFileWriteStr(path, dev->name) < 0) {
             virReportSystemError(conn, errno,
                                  _("Failed to bind PCI device '%s' to %s"),
-                                 dev->name, stub_module);
+                                 dev->name, driver);
             return -1;
         }
     }
 
+    /* Xen's pciback.ko wants you to use remove_slot on the specific device */
+    pciDriverFile(path, sizeof(path), driver, "remove_slot");
+    if (virFileExists(path) && virFileWriteStr(path, dev->name) < 0) {
+        virReportSystemError(conn, errno,
+                             _("Failed to remove slot for PCI device '%s' to %s"),
+                             dev->name, driver);
+        return -1;
+    }
+
+
     /* Trigger a re-probe of the device is not in the stub's dynamic
      * ID table. If the stub is available, but 'remove_id' isn't
      * available, then re-probing would just cause the device to be
      * re-bound to the stub.
      */
-    snprintf(path, sizeof(path), "%s/remove_id", stub_dir);
-    if (!virFileExists(stub_dir) || virFileExists(path)) {
+    pciDriverFile(path, sizeof(path), driver, "remove_id");
+    if (!virFileExists(drvdir) || virFileExists(path)) {
         if (virFileWriteStr(PCI_SYSFS "drivers_probe", dev->name) < 0) {
             virReportSystemError(conn, errno,
                                  _("Failed to trigger a re-probe for PCI device '%s'"),
@@ -746,7 +809,14 @@ pciUnBindDeviceFromStub(virConnectPtr conn, pciDevice *dev, const char *stub_mod
 int
 pciReAttachDevice(virConnectPtr conn, pciDevice *dev)
 {
-    return pciUnBindDeviceFromStub(conn, dev, "pci-stub");
+    const char *driver = pciFindStubDriver(conn);
+    if (!driver) {
+        pciReportError(conn, VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("cannot find any PCI stub module"));
+        return -1;
+    }
+
+    return pciUnBindDeviceFromStub(conn, dev, driver);
 }
 
 static char *
diff --git a/src/xen_unified.c b/src/xen_unified.c
index 04b31192d6..e708980538 100644
--- a/src/xen_unified.c
+++ b/src/xen_unified.c
@@ -43,6 +43,8 @@
 #include "xml.h"
 #include "util.h"
 #include "memory.h"
+#include "node_device_conf.h"
+#include "pci.h"
 
 #define VIR_FROM_THIS VIR_FROM_XEN
 
@@ -1420,6 +1422,123 @@ xenUnifiedDomainEventDeregister (virConnectPtr conn,
     return ret;
 }
 
+
+static int
+xenUnifiedNodeDeviceGetPciInfo (virNodeDevicePtr dev,
+                           unsigned *domain,
+                           unsigned *bus,
+                           unsigned *slot,
+                           unsigned *function)
+{
+    virNodeDeviceDefPtr def = NULL;
+    virNodeDevCapsDefPtr cap;
+    char *xml = NULL;
+    int ret = -1;
+
+    xml = virNodeDeviceGetXMLDesc(dev, 0);
+    if (!xml)
+        goto out;
+
+    def = virNodeDeviceDefParseString(dev->conn, xml);
+    if (!def)
+        goto out;
+
+    cap = def->caps;
+    while (cap) {
+        if (cap->type == VIR_NODE_DEV_CAP_PCI_DEV) {
+            *domain   = cap->data.pci_dev.domain;
+            *bus      = cap->data.pci_dev.bus;
+            *slot     = cap->data.pci_dev.slot;
+            *function = cap->data.pci_dev.function;
+            break;
+        }
+
+        cap = cap->next;
+    }
+
+    if (!cap) {
+        xenUnifiedError(dev->conn, VIR_ERR_INVALID_ARG,
+                        _("device %s is not a PCI device"), dev->name);
+        goto out;
+    }
+
+    ret = 0;
+out:
+    virNodeDeviceDefFree(def);
+    VIR_FREE(xml);
+    return ret;
+}
+
+static int
+xenUnifiedNodeDeviceDettach (virNodeDevicePtr dev)
+{
+    pciDevice *pci;
+    unsigned domain, bus, slot, function;
+    int ret = -1;
+
+    if (xenUnifiedNodeDeviceGetPciInfo(dev, &domain, &bus, &slot, &function) < 0)
+        return -1;
+
+    pci = pciGetDevice(dev->conn, domain, bus, slot, function);
+    if (!pci)
+        return -1;
+
+    if (pciDettachDevice(dev->conn, pci) < 0)
+        goto out;
+
+    ret = 0;
+out:
+    pciFreeDevice(dev->conn, pci);
+    return ret;
+}
+
+static int
+xenUnifiedNodeDeviceReAttach (virNodeDevicePtr dev)
+{
+    pciDevice *pci;
+    unsigned domain, bus, slot, function;
+    int ret = -1;
+
+    if (xenUnifiedNodeDeviceGetPciInfo(dev, &domain, &bus, &slot, &function) < 0)
+        return -1;
+
+    pci = pciGetDevice(dev->conn, domain, bus, slot, function);
+    if (!pci)
+        return -1;
+
+    if (pciReAttachDevice(dev->conn, pci) < 0)
+        goto out;
+
+    ret = 0;
+out:
+    pciFreeDevice(dev->conn, pci);
+    return ret;
+}
+
+static int
+xenUnifiedNodeDeviceReset (virNodeDevicePtr dev)
+{
+    pciDevice *pci;
+    unsigned domain, bus, slot, function;
+    int ret = -1;
+
+    if (xenUnifiedNodeDeviceGetPciInfo(dev, &domain, &bus, &slot, &function) < 0)
+        return -1;
+
+    pci = pciGetDevice(dev->conn, domain, bus, slot, function);
+    if (!pci)
+        return -1;
+
+    if (pciResetDevice(dev->conn, pci) < 0)
+        goto out;
+
+    ret = 0;
+out:
+    pciFreeDevice(dev->conn, pci);
+    return ret;
+}
+
+
 /*----- Register with libvirt.c, and initialise Xen drivers. -----*/
 
 /* The interface which we export upwards to libvirt.c. */
@@ -1486,9 +1605,9 @@ static virDriver xenUnifiedDriver = {
     xenUnifiedDomainEventDeregister, /* domainEventDeregister */
     NULL, /* domainMigratePrepare2 */
     NULL, /* domainMigrateFinish2 */
-    NULL, /* nodeDeviceDettach */
-    NULL, /* nodeDeviceReAttach */
-    NULL, /* nodeDeviceReset */
+    xenUnifiedNodeDeviceDettach, /* nodeDeviceDettach */
+    xenUnifiedNodeDeviceReAttach, /* nodeDeviceReAttach */
+    xenUnifiedNodeDeviceReset, /* nodeDeviceReset */
 };
 
 /**
diff --git a/src/xend_internal.c b/src/xend_internal.c
index 58a63ecd36..2e2fd218e4 100644
--- a/src/xend_internal.c
+++ b/src/xend_internal.c
@@ -92,6 +92,11 @@ xenDaemonFormatSxprNet(virConnectPtr conn ATTRIBUTE_UNUSED,
                        int xendConfigVersion,
                        int isAttach);
 static int
+xenDaemonFormatSxprOnePCI(virConnectPtr conn,
+                          virDomainHostdevDefPtr def,
+                          virBufferPtr buf);
+
+static int
 virDomainXMLDevID(virDomainPtr domain,
                   virDomainDeviceDefPtr dev,
                   char *class,
@@ -2145,6 +2150,131 @@ error:
     return -1;
 }
 
+/**
+ * xenDaemonParseSxprPCI
+ * @conn: connection
+ * @root: root sexpr
+ *
+ * This parses out block devices from the domain sexpr
+ *
+ * Returns 0 if successful or -1 if failed.
+ */
+static int
+xenDaemonParseSxprPCI(virConnectPtr conn,
+                      virDomainDefPtr def,
+                      const struct sexpr *root)
+{
+    const struct sexpr *cur, *tmp = NULL, *node;
+    virDomainHostdevDefPtr dev = NULL;
+
+    /*
+     * With the (domain ...) block we have the following odd setup
+     *
+     * (device
+     *    (pci
+     *       (dev (domain 0x0000) (bus 0x00) (slot 0x1b) (func 0x0))
+     *       (dev (domain 0x0000) (bus 0x00) (slot 0x13) (func 0x0))
+     *    )
+     * )
+     *
+     * Normally there is one (device ...) block per device, but in
+     * wierd world of Xen PCI, once (device ...) covers multiple
+     * devices.
+     */
+
+    for (cur = root; cur->kind == SEXPR_CONS; cur = cur->u.s.cdr) {
+        node = cur->u.s.car;
+        if ((tmp = sexpr_lookup(node, "device/pci")) != NULL)
+            break;
+    }
+
+    if (!tmp)
+        return 0;
+
+    for (cur = tmp; cur->kind == SEXPR_CONS; cur = cur->u.s.cdr) {
+        const char *domain = NULL;
+        const char *bus = NULL;
+        const char *slot = NULL;
+        const char *func = NULL;
+        int domainID;
+        int busID;
+        int slotID;
+        int funcID;
+
+        node = cur->u.s.car;
+        if (!sexpr_lookup(node, "dev"))
+            continue;
+
+        if (!(domain = sexpr_node(node, "dev/domain"))) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         "%s", _("missing PCI domain"));
+            goto error;
+        }
+        if (!(bus = sexpr_node(node, "dev/bus"))) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         "%s", _("missing PCI bus"));
+            goto error;
+        }
+        if (!(slot = sexpr_node(node, "dev/slot"))) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         "%s", _("missing PCI slot"));
+            goto error;
+        }
+        if (!(func = sexpr_node(node, "dev/func"))) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         "%s", _("missing PCI func"));
+            goto error;
+        }
+
+        if (virStrToLong_i(domain, NULL, 0, &domainID) < 0) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         _("cannot parse PCI domain '%s'"), domain);
+            goto error;
+        }
+        if (virStrToLong_i(bus, NULL, 0, &busID) < 0) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         _("cannot parse PCI bus '%s'"), bus);
+            goto error;
+        }
+        if (virStrToLong_i(slot, NULL, 0, &slotID) < 0) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         _("cannot parse PCI slot '%s'"), slot);
+            goto error;
+        }
+        if (virStrToLong_i(func, NULL, 0, &funcID) < 0) {
+            virXendError(conn, VIR_ERR_INTERNAL_ERROR,
+                         _("cannot parse PCI func '%s'"), func);
+            goto error;
+        }
+
+        if (VIR_ALLOC(dev) < 0)
+            goto no_memory;
+
+        dev->mode = VIR_DOMAIN_HOSTDEV_MODE_SUBSYS;
+        dev->managed = 0;
+        dev->source.subsys.type = VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI;
+        dev->source.subsys.u.pci.domain = domainID;
+        dev->source.subsys.u.pci.bus = busID;
+        dev->source.subsys.u.pci.slot = slotID;
+        dev->source.subsys.u.pci.function = funcID;
+
+        if (VIR_REALLOC_N(def->hostdevs, def->nhostdevs+1) < 0) {
+            goto no_memory;
+        }
+
+        def->hostdevs[def->nhostdevs++] = dev;
+    }
+
+    return 0;
+
+no_memory:
+    virReportOOMError(conn);
+
+error:
+    virDomainHostdevDefFree(dev);
+    return -1;
+}
+
 
 /**
  * xenDaemonParseSxpr:
@@ -2315,6 +2445,9 @@ xenDaemonParseSxpr(virConnectPtr conn,
     if (xenDaemonParseSxprNets(conn, def, root) < 0)
         goto error;
 
+    if (xenDaemonParseSxprPCI(conn, def, root) < 0)
+        goto error;
+
     /* New style graphics device config */
     if (xenDaemonParseSxprGraphicsNew(conn, def, root) < 0)
         goto error;
@@ -3956,6 +4089,20 @@ xenDaemonAttachDevice(virDomainPtr domain, const char *xml)
             goto cleanup;
         break;
 
+    case VIR_DOMAIN_DEVICE_HOSTDEV:
+        if (dev->data.hostdev->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS &&
+            dev->data.hostdev->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI) {
+            if (xenDaemonFormatSxprOnePCI(domain->conn,
+                                          dev->data.hostdev,
+                                          &buf) < 0)
+                goto cleanup;
+        } else {
+            virXendError(domain->conn, VIR_ERR_NO_SUPPORT, "%s",
+                         _("unsupported device type"));
+            goto cleanup;
+        }
+        break;
+
     default:
         virXendError(domain->conn, VIR_ERR_NO_SUPPORT, "%s",
                      _("unsupported device type"));
@@ -5266,6 +5413,85 @@ xenDaemonFormatSxprNet(virConnectPtr conn,
     return 0;
 }
 
+
+static void
+xenDaemonFormatSxprPCI(virDomainHostdevDefPtr def,
+                       virBufferPtr buf)
+{
+    virBufferVSprintf(buf, "(dev (domain 0x%04x)(bus 0x%02x)(slot 0x%02x)(func 0x%x))",
+                      def->source.subsys.u.pci.domain,
+                      def->source.subsys.u.pci.bus,
+                      def->source.subsys.u.pci.slot,
+                      def->source.subsys.u.pci.function);
+}
+
+static int
+xenDaemonFormatSxprOnePCI(virConnectPtr conn,
+                          virDomainHostdevDefPtr def,
+                          virBufferPtr buf)
+{
+    if (def->managed) {
+        virXendError(conn, VIR_ERR_NO_SUPPORT, "%s",
+                     _("managed PCI devices not supported with XenD"));
+        return -1;
+    }
+
+    virBufferAddLit(buf, "(pci ");
+    xenDaemonFormatSxprPCI(def, buf);
+    virBufferAddLit(buf, ")");
+
+    return 0;
+}
+
+static int
+xenDaemonFormatSxprAllPCI(virConnectPtr conn,
+                          virDomainDefPtr def,
+                          virBufferPtr buf)
+{
+    int hasPCI = 0;
+    int 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_PCI)
+            hasPCI = 1;
+
+    if (!hasPCI)
+        return 0;
+
+    /*
+     * With the (domain ...) block we have the following odd setup
+     *
+     * (device
+     *    (pci
+     *       (dev (domain 0x0000) (bus 0x00) (slot 0x1b) (func 0x0))
+     *       (dev (domain 0x0000) (bus 0x00) (slot 0x13) (func 0x0))
+     *    )
+     * )
+     *
+     * Normally there is one (device ...) block per device, but in
+     * wierd world of Xen PCI, once (device ...) covers multiple
+     * devices.
+     */
+
+    virBufferAddLit(buf, "(device (pci ");
+    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_PCI) {
+            if (def->hostdevs[i]->managed) {
+                virXendError(conn, VIR_ERR_NO_SUPPORT, "%s",
+                             _("managed PCI devices not supported with XenD"));
+                return -1;
+            }
+
+            xenDaemonFormatSxprPCI(def->hostdevs[i], buf);
+        }
+    }
+    virBufferAddLit(buf, "))");
+
+    return 0;
+}
+
 int
 xenDaemonFormatSxprSound(virConnectPtr conn,
                          virDomainDefPtr def,
@@ -5537,6 +5763,9 @@ xenDaemonFormatSxpr(virConnectPtr conn,
                                    &buf, hvm, xendConfigVersion, 0) < 0)
             goto error;
 
+    if (xenDaemonFormatSxprAllPCI(conn, def, &buf) < 0)
+        goto error;
+
     /* New style PV graphics config xen >= 3.0.4,
      * or HVM graphics config xen >= 3.0.5 */
     if ((xendConfigVersion >= XEND_CONFIG_MIN_VERS_PVFB_NEWCONF && !hvm) ||
@@ -5624,6 +5853,9 @@ virDomainXMLDevID(virDomainPtr domain,
         strncpy(ref, xref, ref_len);
         free(xref);
         ref[ref_len - 1] = '\0';
+    } else if (dev->type == VIR_DOMAIN_DEVICE_HOSTDEV &&
+               dev->data.hostdev->mode == VIR_DOMAIN_HOSTDEV_MODE_SUBSYS &&
+               dev->data.hostdev->source.subsys.type == VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI) {
     } else {
         virXendError(NULL, VIR_ERR_NO_SUPPORT,
                      "%s", _("hotplug of device type not supported"));
diff --git a/src/xm_internal.c b/src/xm_internal.c
index d9678c0364..26e8d01bec 100644
--- a/src/xm_internal.c
+++ b/src/xm_internal.c
@@ -672,6 +672,7 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) {
     virDomainDiskDefPtr disk = NULL;
     virDomainNetDefPtr net = NULL;
     virDomainGraphicsDefPtr graphics = NULL;
+    virDomainHostdevDefPtr hostdev = NULL;
     int i;
     const char *defaultArch, *defaultMachine;
 
@@ -1126,6 +1127,88 @@ xenXMDomainConfigParse(virConnectPtr conn, virConfPtr conf) {
         }
     }
 
+    list = virConfGetValue(conf, "pci");
+    if (list && list->type == VIR_CONF_LIST) {
+        list = list->list;
+        while (list) {
+            char domain[5];
+            char bus[3];
+            char slot[3];
+            char func[2];
+            char *key, *nextkey;
+            int domainID;
+            int busID;
+            int slotID;
+            int funcID;
+
+            domain[0] = bus[0] = slot[0] = func[0] = '\0';
+
+            if ((list->type != VIR_CONF_STRING) || (list->str == NULL))
+                goto skippci;
+
+            /* pci=['0000:00:1b.0','0000:00:13.0'] */
+            key = list->str;
+            if (!(key = list->str))
+                goto skippci;
+            if (!(nextkey = strchr(key, ':')))
+                goto skippci;
+
+            if ((nextkey - key) > (sizeof(domain)-1))
+                goto skippci;
+
+            strncpy(domain, key, sizeof(domain));
+            domain[sizeof(domain)-1] = '\0';
+
+            key = nextkey + 1;
+            if (!(nextkey = strchr(key, ':')))
+                goto skippci;
+
+            strncpy(bus, key, sizeof(bus));
+            bus[sizeof(bus)-1] = '\0';
+
+            key = nextkey + 1;
+            if (!(nextkey = strchr(key, '.')))
+                goto skippci;
+
+            strncpy(slot, key, sizeof(slot));
+            slot[sizeof(slot)-1] = '\0';
+
+            key = nextkey + 1;
+            if (strlen(key) != 1)
+                goto skippci;
+
+            strncpy(func, key, sizeof(func));
+            func[sizeof(func)-1] = '\0';
+
+            if (virStrToLong_i(domain, NULL, 16, &domainID) < 0)
+                goto skippci;
+            if (virStrToLong_i(bus, NULL, 16, &busID) < 0)
+                goto skippci;
+            if (virStrToLong_i(slot, NULL, 16, &slotID) < 0)
+                goto skippci;
+            if (virStrToLong_i(func, NULL, 16, &funcID) < 0)
+                goto skippci;
+
+            if (VIR_ALLOC(hostdev) < 0)
+                goto cleanup;
+
+            hostdev->managed = 0;
+            hostdev->source.subsys.type = VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI;
+            hostdev->source.subsys.u.pci.domain = domainID;
+            hostdev->source.subsys.u.pci.bus = busID;
+            hostdev->source.subsys.u.pci.slot = slotID;
+            hostdev->source.subsys.u.pci.function = funcID;
+
+            if (VIR_REALLOC_N(def->hostdevs, def->nhostdevs+1) < 0)
+                goto no_memory;
+            def->hostdevs[def->nhostdevs++] = hostdev;
+            hostdev = NULL;
+
+        skippci:
+            list = list->next;
+        }
+    }
+
     if (hvm) {
         if (xenXMConfigGetString(conn, conf, "usbdevice", &str, NULL) < 0)
             goto cleanup;
@@ -1951,6 +2034,76 @@ cleanup:
 
 
 
+static int
+xenXMDomainConfigFormatPCI(virConnectPtr conn,
+                           virConfPtr conf,
+                           virDomainDefPtr def)
+{
+
+    virConfValuePtr pciVal = NULL;
+    int hasPCI = 0;
+    int 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_PCI)
+            hasPCI = 1;
+
+    if (!hasPCI)
+        return 0;
+
+    if (VIR_ALLOC(pciVal) < 0)
+        return -1;
+
+    pciVal->type = VIR_CONF_LIST;
+    pciVal->list = NULL;
+
+    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_PCI) {
+            virConfValuePtr val, tmp;
+            char *buf;
+
+            if (virAsprintf(&buf, "%04x:%02x:%02x.%x",
+                            def->hostdevs[i]->source.subsys.u.pci.domain,
+                            def->hostdevs[i]->source.subsys.u.pci.bus,
+                            def->hostdevs[i]->source.subsys.u.pci.slot,
+                            def->hostdevs[i]->source.subsys.u.pci.function) < 0)
+                goto error;
+
+            if (VIR_ALLOC(val) < 0) {
+                VIR_FREE(buf);
+                virReportOOMError(conn);
+                goto error;
+            }
+            val->type = VIR_CONF_STRING;
+            val->str = buf;
+            tmp = pciVal->list;
+            while (tmp && tmp->next)
+                tmp = tmp->next;
+            if (tmp)
+                tmp->next = val;
+            else
+                pciVal->list = val;
+        }
+    }
+
+    if (pciVal->list != NULL) {
+        int ret = virConfSetValue(conf, "pci", pciVal);
+        pciVal = NULL;
+        if (ret < 0)
+            return -1;
+    }
+    VIR_FREE(pciVal);
+
+    return 0;
+
+error:
+    virConfFreeValue(pciVal);
+    return -1;
+}
+
+
 virConfPtr xenXMDomainConfigFormat(virConnectPtr conn,
                                    virDomainDefPtr def) {
     virConfPtr conf = NULL;
@@ -2272,6 +2425,9 @@ virConfPtr xenXMDomainConfigFormat(virConnectPtr conn,
     }
     VIR_FREE(netVal);
 
+    if (xenXMDomainConfigFormatPCI(conn, conf, def) < 0)
+        goto cleanup;
+
     if (hvm) {
         if (def->nparallels) {
             virBuffer buf = VIR_BUFFER_INITIALIZER;
diff --git a/tests/sexpr2xmldata/sexpr2xml-pci-devs.sexpr b/tests/sexpr2xmldata/sexpr2xml-pci-devs.sexpr
new file mode 100644
index 0000000000..cc16e06e09
--- /dev/null
+++ b/tests/sexpr2xmldata/sexpr2xml-pci-devs.sexpr
@@ -0,0 +1,2 @@
+(domain (domid 6)(name 'pvtest')(memory 420)(maxmem 420)(vcpus 2)(uuid '596a5d2171f48fb2e068e2386a5c413e')(on_poweroff 'destroy')(on_reboot 'destroy')(on_crash 'destroy')(image (linux (kernel '/var/lib/xen/vmlinuz.2Dn2YT')(ramdisk '/var/lib/xen/initrd.img.0u-Vhq')(args ' method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  ')))(device (pci (backend 0)(dev (domain 0x0001) (bus 0x0c) (slot 0x1b) (func 0x2))(dev (domain 0x0000) (bus 0x01) (slot 0x13) (func 0x0))))(device (vbd (dev 'xvda')(uname 'phy:/dev/MainVG/GuestVG')(mode 'w'))))
+
diff --git a/tests/sexpr2xmldata/sexpr2xml-pci-devs.xml b/tests/sexpr2xmldata/sexpr2xml-pci-devs.xml
new file mode 100644
index 0000000000..40e12c014f
--- /dev/null
+++ b/tests/sexpr2xmldata/sexpr2xml-pci-devs.xml
@@ -0,0 +1,37 @@
+<domain type='xen' id='6'>
+  <name>pvtest</name>
+  <uuid>596a5d21-71f4-8fb2-e068-e2386a5c413e</uuid>
+  <memory>430080</memory>
+  <currentMemory>430080</currentMemory>
+  <vcpu>2</vcpu>
+  <os>
+    <type>linux</type>
+    <kernel>/var/lib/xen/vmlinuz.2Dn2YT</kernel>
+    <initrd>/var/lib/xen/initrd.img.0u-Vhq</initrd>
+    <cmdline> method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  </cmdline>
+  </os>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>destroy</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <disk type='block' device='disk'>
+      <driver name='phy'/>
+      <source dev='/dev/MainVG/GuestVG'/>
+      <target dev='xvda' bus='xen'/>
+    </disk>
+    <console type='pty'>
+      <target port='0'/>
+    </console>
+    <hostdev mode='subsystem' type='pci' managed='no'>
+      <source>
+        <address domain='0x0001' bus='0x0c' slot='0x1b' function='0x2'/>
+      </source>
+    </hostdev>
+    <hostdev mode='subsystem' type='pci' managed='no'>
+      <source>
+        <address domain='0x0000' bus='0x01' slot='0x13' function='0x0'/>
+      </source>
+    </hostdev>
+  </devices>
+</domain>
diff --git a/tests/sexpr2xmltest.c b/tests/sexpr2xmltest.c
index 42e11a4c5f..be40913fde 100644
--- a/tests/sexpr2xmltest.c
+++ b/tests/sexpr2xmltest.c
@@ -145,6 +145,7 @@ mymain(int argc, char **argv)
     DO_TEST("bridge-ipaddr", "bridge-ipaddr", 3);
     DO_TEST("no-source-cdrom", "no-source-cdrom", 2);
     DO_TEST("pv-localtime", "pv-localtime", 2);
+    DO_TEST("pci-devs", "pci-devs", 2);
 
     DO_TEST("fv-utc", "fv-utc", 1);
     DO_TEST("fv-localtime", "fv-localtime", 1);
diff --git a/tests/xmconfigdata/test-pci-devs.cfg b/tests/xmconfigdata/test-pci-devs.cfg
new file mode 100644
index 0000000000..e6f1154dfe
--- /dev/null
+++ b/tests/xmconfigdata/test-pci-devs.cfg
@@ -0,0 +1,24 @@
+name = "test"
+uuid = "cc2315e7-d26a-307a-438c-6d188ec4c09c"
+maxmem = 382
+memory = 350
+vcpus = 1
+builder = "hvm"
+kernel = "/usr/lib/xen/boot/hvmloader"
+boot = "c"
+pae = 1
+acpi = 1
+apic = 1
+localtime = 0
+on_poweroff = "destroy"
+on_reboot = "destroy"
+on_crash = "destroy"
+device_model = "/usr/lib/xen/bin/qemu-dm"
+sdl = 0
+vnc = 1
+vncunused = 1
+disk = [ "phy:/dev/sda8,hda,w", ",hdc:cdrom,r" ]
+vif = [ "mac=00:16:3e:0a:7b:39,bridge=xenbr0,type=ioemu" ]
+pci = [ "0001:0c:1b.2", "0000:01:13.0" ]
+parallel = "none"
+serial = "pty"
diff --git a/tests/xmconfigdata/test-pci-devs.xml b/tests/xmconfigdata/test-pci-devs.xml
new file mode 100644
index 0000000000..6c44e233cc
--- /dev/null
+++ b/tests/xmconfigdata/test-pci-devs.xml
@@ -0,0 +1,56 @@
+<domain type='xen'>
+  <name>test</name>
+  <uuid>cc2315e7-d26a-307a-438c-6d188ec4c09c</uuid>
+  <memory>391168</memory>
+  <currentMemory>358400</currentMemory>
+  <vcpu>1</vcpu>
+  <os>
+    <type arch='i686' machine='xenfv'>hvm</type>
+    <loader>/usr/lib/xen/boot/hvmloader</loader>
+    <boot dev='hd'/>
+  </os>
+  <features>
+    <acpi/>
+    <apic/>
+    <pae/>
+  </features>
+  <clock offset='utc'/>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>destroy</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <emulator>/usr/lib/xen/bin/qemu-dm</emulator>
+    <disk type='block' device='disk'>
+      <driver name='phy'/>
+      <source dev='/dev/sda8'/>
+      <target dev='hda' bus='ide'/>
+    </disk>
+    <disk type='block' device='cdrom'>
+      <driver name='phy'/>
+      <target dev='hdc' bus='ide'/>
+      <readonly/>
+    </disk>
+    <interface type='bridge'>
+      <mac address='00:16:3e:0a:7b:39'/>
+      <source bridge='xenbr0'/>
+    </interface>
+    <serial type='pty'>
+      <target port='0'/>
+    </serial>
+    <console type='pty'>
+      <target port='0'/>
+    </console>
+    <input type='mouse' bus='ps2'/>
+    <graphics type='vnc' port='-1' autoport='yes'/>
+    <hostdev mode='subsystem' type='pci' managed='no'>
+      <source>
+        <address domain='0x0001' bus='0x0c' slot='0x1b' function='0x2'/>
+      </source>
+    </hostdev>
+    <hostdev mode='subsystem' type='pci' managed='no'>
+      <source>
+        <address domain='0x0000' bus='0x01' slot='0x13' function='0x0'/>
+      </source>
+    </hostdev>
+  </devices>
+</domain>
diff --git a/tests/xmconfigtest.c b/tests/xmconfigtest.c
index f25cf056b0..d49f0106c2 100644
--- a/tests/xmconfigtest.c
+++ b/tests/xmconfigtest.c
@@ -232,6 +232,7 @@ mymain(int argc, char **argv)
 
     DO_TEST("escape-paths", 2);
     DO_TEST("no-source-cdrom", 2);
+    DO_TEST("pci-devs", 2);
 
     virCapabilitiesFree(caps);
 
diff --git a/tests/xml2sexprdata/xml2sexpr-pci-devs.sexpr b/tests/xml2sexprdata/xml2sexpr-pci-devs.sexpr
new file mode 100644
index 0000000000..b767932118
--- /dev/null
+++ b/tests/xml2sexprdata/xml2sexpr-pci-devs.sexpr
@@ -0,0 +1 @@
+(vm (name 'pvtest')(memory 420)(maxmem 420)(vcpus 2)(uuid '596a5d21-71f4-8fb2-e068-e2386a5c413e')(on_poweroff 'destroy')(on_reboot 'destroy')(on_crash 'destroy')(image (linux (kernel '/var/lib/xen/vmlinuz.2Dn2YT')(ramdisk '/var/lib/xen/initrd.img.0u-Vhq')(args ' method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  ')))(device (vbd (dev 'xvda')(uname 'phy:/dev/MainVG/GuestLV')(mode 'w')))(device (pci (dev (domain 0x0001)(bus 0x0c)(slot 0x1b)(func 0x2))(dev (domain 0x0000)(bus 0x01)(slot 0x13)(func 0x0)))))
\ No newline at end of file
diff --git a/tests/xml2sexprdata/xml2sexpr-pci-devs.xml b/tests/xml2sexprdata/xml2sexpr-pci-devs.xml
new file mode 100644
index 0000000000..60b204b855
--- /dev/null
+++ b/tests/xml2sexprdata/xml2sexpr-pci-devs.xml
@@ -0,0 +1,33 @@
+<domain type='xen' id='15'>
+  <name>pvtest</name>
+  <uuid>596a5d2171f48fb2e068e2386a5c413e</uuid>
+  <os>
+    <type>linux</type>
+    <kernel>/var/lib/xen/vmlinuz.2Dn2YT</kernel>
+    <initrd>/var/lib/xen/initrd.img.0u-Vhq</initrd>
+    <cmdline> method=http://download.fedora.devel.redhat.com/pub/fedora/linux/core/test/5.91/x86_64/os  </cmdline>
+  </os>
+  <memory>430080</memory>
+  <vcpu>2</vcpu>
+  <on_poweroff>destroy</on_poweroff>
+  <on_reboot>destroy</on_reboot>
+  <on_crash>destroy</on_crash>
+  <devices>
+    <disk type='block' device='disk'>
+      <source dev='/dev/MainVG/GuestLV'/>
+      <target dev='xvda'/>
+    </disk>
+    <console tty='/dev/pts/4'/>
+    <hostdev mode='subsystem' type='pci' managed='no'>
+      <source>
+        <address domain='0x0001' bus='0x0c' slot='0x1b' function='0x2'/>
+      </source>
+    </hostdev>
+    <hostdev mode='subsystem' type='pci' managed='no'>
+      <source>
+        <address domain='0x0000' bus='0x01' slot='0x13' function='0x0'/>
+      </source>
+    </hostdev>
+  </devices>
+</domain>
+
diff --git a/tests/xml2sexprtest.c b/tests/xml2sexprtest.c
index 10ff84476e..69da1ffc0a 100644
--- a/tests/xml2sexprtest.c
+++ b/tests/xml2sexprtest.c
@@ -130,6 +130,7 @@ mymain(int argc, char **argv)
     DO_TEST("bridge-ipaddr", "bridge-ipaddr", "pvtest", 2);
     DO_TEST("no-source-cdrom", "no-source-cdrom", "test", 2);
     DO_TEST("pv-localtime", "pv-localtime", "pvtest", 1);
+    DO_TEST("pci-devs", "pci-devs", "pvtest", 2);
 
     DO_TEST("fv-utc", "fv-utc", "fvtest", 1);
     DO_TEST("fv-localtime", "fv-localtime", "fvtest", 1);