21 files changed, 184 insertions, 100 deletions

diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index f7d6f47971fd..24f485827e03 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -278,7 +278,7 @@ config XEN_PRIVCMD_EVENTFD
 
 config XEN_ACPI_PROCESSOR
 	tristate "Xen ACPI processor"
-	depends on XEN && XEN_PV_DOM0 && X86 && ACPI_PROCESSOR && CPU_FREQ
+	depends on XEN && XEN_DOM0 && X86 && ACPI_PROCESSOR && CPU_FREQ
 	default m
 	help
 	  This ACPI processor uploads Power Management information to the Xen
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 528395133b4f..2de37dcd7556 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -84,7 +84,7 @@ module_param(balloon_boot_timeout, uint, 0444);
 #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
 static int xen_hotplug_unpopulated;
 
-static struct ctl_table balloon_table[] = {
+static const struct ctl_table balloon_table[] = {
 	{
 		.procname	= "hotplug_unpopulated",
 		.data		= &xen_hotplug_unpopulated,
@@ -157,6 +157,8 @@ static void balloon_append(struct page *page)
 		list_add(&page->lru, &ballooned_pages);
 		balloon_stats.balloon_low++;
 	}
+	inc_node_page_state(page, NR_BALLOON_PAGES);
+
 	wake_up(&balloon_wq);
 }
 
@@ -179,6 +181,8 @@ static struct page *balloon_retrieve(bool require_lowmem)
 		balloon_stats.balloon_low--;
 
 	__ClearPageOffline(page);
+	dec_node_page_state(page, NR_BALLOON_PAGES);
+
 	return page;
 }
 
@@ -675,7 +679,7 @@ void xen_free_ballooned_pages(unsigned int nr_pages, struct page **pages)
 }
 EXPORT_SYMBOL(xen_free_ballooned_pages);
 
-static void __init balloon_add_regions(void)
+static int __init balloon_add_regions(void)
 {
 	unsigned long start_pfn, pages;
 	unsigned long pfn, extra_pfn_end;
@@ -698,26 +702,41 @@ static void __init balloon_add_regions(void)
 		for (pfn = start_pfn; pfn < extra_pfn_end; pfn++)
 			balloon_append(pfn_to_page(pfn));
 
-		balloon_stats.total_pages += extra_pfn_end - start_pfn;
+		/*
+		 * Extra regions are accounted for in the physmap, but need
+		 * decreasing from current_pages and target_pages to balloon
+		 * down the initial allocation, because they are already
+		 * accounted for in total_pages.
+		 */
+		pages = extra_pfn_end - start_pfn;
+		if (pages >= balloon_stats.current_pages ||
+		    pages >= balloon_stats.target_pages) {
+			WARN(1, "Extra pages underflow current target");
+			return -ERANGE;
+		}
+		balloon_stats.current_pages -= pages;
+		balloon_stats.target_pages -= pages;
 	}
+
+	return 0;
 }
 
 static int __init balloon_init(void)
 {
 	struct task_struct *task;
+	int rc;
 
 	if (!xen_domain())
 		return -ENODEV;
 
 	pr_info("Initialising balloon driver\n");
 
-#ifdef CONFIG_XEN_PV
-	balloon_stats.current_pages = xen_pv_domain()
-		? min(xen_start_info->nr_pages - xen_released_pages, max_pfn)
-		: get_num_physpages();
-#else
-	balloon_stats.current_pages = get_num_physpages();
-#endif
+	if (xen_released_pages >= get_num_physpages()) {
+		WARN(1, "Released pages underflow current target");
+		return -ERANGE;
+	}
+
+	balloon_stats.current_pages = get_num_physpages() - xen_released_pages;
 	balloon_stats.target_pages  = balloon_stats.current_pages;
 	balloon_stats.balloon_low   = 0;
 	balloon_stats.balloon_high  = 0;
@@ -734,7 +753,9 @@ static int __init balloon_init(void)
 	register_sysctl_init("xen/balloon", balloon_table);
 #endif
 
-	balloon_add_regions();
+	rc = balloon_add_regions();
+	if (rc)
+		return rc;
 
 	task = kthread_run(balloon_thread, NULL, "xen-balloon");
 	if (IS_ERR(task)) {
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 985e155ebe4b..41309d38f78c 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -722,12 +722,6 @@ static struct irq_info *xen_irq_init(unsigned int irq)
 		INIT_RCU_WORK(&info->rwork, delayed_free_irq);
 
 		set_info_for_irq(irq, info);
-		/*
-		 * Interrupt affinity setting can be immediate. No point
-		 * in delaying it until an interrupt is handled.
-		 */
-		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
-
 		INIT_LIST_HEAD(&info->eoi_list);
 		list_add_tail(&info->list, &xen_irq_list_head);
 	}
diff --git a/drivers/xen/gntdev-common.h b/drivers/xen/gntdev-common.h
index 9c286b2a1900..ac8ce3179ba2 100644
--- a/drivers/xen/gntdev-common.h
+++ b/drivers/xen/gntdev-common.h
@@ -26,6 +26,10 @@ struct gntdev_priv {
 	/* lock protects maps and freeable_maps. */
 	struct mutex lock;
 
+	/* Free instances of struct gntdev_copy_batch. */
+	struct gntdev_copy_batch *batch;
+	struct mutex batch_lock;
+
 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
 	/* Device for which DMA memory is allocated. */
 	struct device *dma_dev;
diff --git a/drivers/xen/gntdev-dmabuf.c b/drivers/xen/gntdev-dmabuf.c
index 5453d86324f6..82855105ab85 100644
--- a/drivers/xen/gntdev-dmabuf.c
+++ b/drivers/xen/gntdev-dmabuf.c
@@ -357,8 +357,11 @@ struct gntdev_dmabuf_export_args {
 static int dmabuf_exp_from_pages(struct gntdev_dmabuf_export_args *args)
 {
 	DEFINE_DMA_BUF_EXPORT_INFO(exp_info);
-	struct gntdev_dmabuf *gntdev_dmabuf;
-	int ret;
+	struct gntdev_dmabuf *gntdev_dmabuf __free(kfree) = NULL;
+	CLASS(get_unused_fd, ret)(O_CLOEXEC);
+
+	if (ret < 0)
+		return ret;
 
 	gntdev_dmabuf = kzalloc(sizeof(*gntdev_dmabuf), GFP_KERNEL);
 	if (!gntdev_dmabuf)
@@ -383,32 +386,21 @@ static int dmabuf_exp_from_pages(struct gntdev_dmabuf_export_args *args)
 	exp_info.priv = gntdev_dmabuf;
 
 	gntdev_dmabuf->dmabuf = dma_buf_export(&exp_info);
-	if (IS_ERR(gntdev_dmabuf->dmabuf)) {
-		ret = PTR_ERR(gntdev_dmabuf->dmabuf);
-		gntdev_dmabuf->dmabuf = NULL;
-		goto fail;
-	}
-
-	ret = dma_buf_fd(gntdev_dmabuf->dmabuf, O_CLOEXEC);
-	if (ret < 0)
-		goto fail;
+	if (IS_ERR(gntdev_dmabuf->dmabuf))
+		return PTR_ERR(gntdev_dmabuf->dmabuf);
 
 	gntdev_dmabuf->fd = ret;
 	args->fd = ret;
 
 	pr_debug("Exporting DMA buffer with fd %d\n", ret);
 
+	get_file(gntdev_dmabuf->priv->filp);
 	mutex_lock(&args->dmabuf_priv->lock);
 	list_add(&gntdev_dmabuf->next, &args->dmabuf_priv->exp_list);
 	mutex_unlock(&args->dmabuf_priv->lock);
-	get_file(gntdev_dmabuf->priv->filp);
-	return 0;
 
-fail:
-	if (gntdev_dmabuf->dmabuf)
-		dma_buf_put(gntdev_dmabuf->dmabuf);
-	kfree(gntdev_dmabuf);
-	return ret;
+	fd_install(take_fd(ret), no_free_ptr(gntdev_dmabuf)->dmabuf->file);
+	return 0;
 }
 
 static struct gntdev_grant_map *
diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c
index 61faea1f0663..1f2160765618 100644
--- a/drivers/xen/gntdev.c
+++ b/drivers/xen/gntdev.c
@@ -56,6 +56,18 @@ MODULE_AUTHOR("Derek G. Murray <Derek.Murray@cl.cam.ac.uk>, "
 	      "Gerd Hoffmann <kraxel@redhat.com>");
 MODULE_DESCRIPTION("User-space granted page access driver");
 
+#define GNTDEV_COPY_BATCH 16
+
+struct gntdev_copy_batch {
+	struct gnttab_copy ops[GNTDEV_COPY_BATCH];
+	struct page *pages[GNTDEV_COPY_BATCH];
+	s16 __user *status[GNTDEV_COPY_BATCH];
+	unsigned int nr_ops;
+	unsigned int nr_pages;
+	bool writeable;
+	struct gntdev_copy_batch *next;
+};
+
 static unsigned int limit = 64*1024;
 module_param(limit, uint, 0644);
 MODULE_PARM_DESC(limit,
@@ -584,6 +596,8 @@ static int gntdev_open(struct inode *inode, struct file *flip)
 	INIT_LIST_HEAD(&priv->maps);
 	mutex_init(&priv->lock);
 
+	mutex_init(&priv->batch_lock);
+
 #ifdef CONFIG_XEN_GNTDEV_DMABUF
 	priv->dmabuf_priv = gntdev_dmabuf_init(flip);
 	if (IS_ERR(priv->dmabuf_priv)) {
@@ -608,6 +622,7 @@ static int gntdev_release(struct inode *inode, struct file *flip)
 {
 	struct gntdev_priv *priv = flip->private_data;
 	struct gntdev_grant_map *map;
+	struct gntdev_copy_batch *batch;
 
 	pr_debug("priv %p\n", priv);
 
@@ -620,6 +635,14 @@ static int gntdev_release(struct inode *inode, struct file *flip)
 	}
 	mutex_unlock(&priv->lock);
 
+	mutex_lock(&priv->batch_lock);
+	while (priv->batch) {
+		batch = priv->batch;
+		priv->batch = batch->next;
+		kfree(batch);
+	}
+	mutex_unlock(&priv->batch_lock);
+
 #ifdef CONFIG_XEN_GNTDEV_DMABUF
 	gntdev_dmabuf_fini(priv->dmabuf_priv);
 #endif
@@ -785,17 +808,6 @@ static long gntdev_ioctl_notify(struct gntdev_priv *priv, void __user *u)
 	return rc;
 }
 
-#define GNTDEV_COPY_BATCH 16
-
-struct gntdev_copy_batch {
-	struct gnttab_copy ops[GNTDEV_COPY_BATCH];
-	struct page *pages[GNTDEV_COPY_BATCH];
-	s16 __user *status[GNTDEV_COPY_BATCH];
-	unsigned int nr_ops;
-	unsigned int nr_pages;
-	bool writeable;
-};
-
 static int gntdev_get_page(struct gntdev_copy_batch *batch, void __user *virt,
 				unsigned long *gfn)
 {
@@ -953,36 +965,53 @@ static int gntdev_grant_copy_seg(struct gntdev_copy_batch *batch,
 static long gntdev_ioctl_grant_copy(struct gntdev_priv *priv, void __user *u)
 {
 	struct ioctl_gntdev_grant_copy copy;
-	struct gntdev_copy_batch batch;
+	struct gntdev_copy_batch *batch;
 	unsigned int i;
 	int ret = 0;
 
 	if (copy_from_user(&copy, u, sizeof(copy)))
 		return -EFAULT;
 
-	batch.nr_ops = 0;
-	batch.nr_pages = 0;
+	mutex_lock(&priv->batch_lock);
+	if (!priv->batch) {
+		batch = kmalloc(sizeof(*batch), GFP_KERNEL);
+	} else {
+		batch = priv->batch;
+		priv->batch = batch->next;
+	}
+	mutex_unlock(&priv->batch_lock);
+	if (!batch)
+		return -ENOMEM;
+
+	batch->nr_ops = 0;
+	batch->nr_pages = 0;
 
 	for (i = 0; i < copy.count; i++) {
 		struct gntdev_grant_copy_segment seg;
 
 		if (copy_from_user(&seg, &copy.segments[i], sizeof(seg))) {
 			ret = -EFAULT;
+			gntdev_put_pages(batch);
 			goto out;
 		}
 
-		ret = gntdev_grant_copy_seg(&batch, &seg, &copy.segments[i].status);
-		if (ret < 0)
+		ret = gntdev_grant_copy_seg(batch, &seg, &copy.segments[i].status);
+		if (ret < 0) {
+			gntdev_put_pages(batch);
 			goto out;
+		}
 
 		cond_resched();
 	}
-	if (batch.nr_ops)
-		ret = gntdev_copy(&batch);
-	return ret;
+	if (batch->nr_ops)
+		ret = gntdev_copy(batch);
+
+ out:
+	mutex_lock(&priv->batch_lock);
+	batch->next = priv->batch;
+	priv->batch = batch;
+	mutex_unlock(&priv->batch_lock);
 
-  out:
-	gntdev_put_pages(&batch);
 	return ret;
 }
 
diff --git a/drivers/xen/pci.c b/drivers/xen/pci.c
index 416f231809cb..bfe07adb3e3a 100644
--- a/drivers/xen/pci.c
+++ b/drivers/xen/pci.c
@@ -43,6 +43,18 @@ static int xen_add_device(struct device *dev)
 		pci_mcfg_reserved = true;
 	}
 #endif
+
+	if (pci_domain_nr(pci_dev->bus) >> 16) {
+		/*
+		 * The hypercall interface is limited to 16bit PCI segment
+		 * values, do not attempt to register devices with Xen in
+		 * segments greater or equal than 0x10000.
+		 */
+		dev_info(dev,
+			 "not registering with Xen: invalid PCI segment\n");
+		return 0;
+	}
+
 	if (pci_seg_supported) {
 		DEFINE_RAW_FLEX(struct physdev_pci_device_add, add, optarr, 1);
 
@@ -149,6 +161,16 @@ static int xen_remove_device(struct device *dev)
 	int r;
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 
+	if (pci_domain_nr(pci_dev->bus) >> 16) {
+		/*
+		 * The hypercall interface is limited to 16bit PCI segment
+		 * values.
+		 */
+		dev_info(dev,
+			 "not unregistering with Xen: invalid PCI segment\n");
+		return 0;
+	}
+
 	if (pci_seg_supported) {
 		struct physdev_pci_device device = {
 			.seg = pci_domain_nr(pci_dev->bus),
@@ -182,6 +204,16 @@ int xen_reset_device(const struct pci_dev *dev)
 		.flags = PCI_DEVICE_RESET_FLR,
 	};
 
+	if (pci_domain_nr(dev->bus) >> 16) {
+		/*
+		 * The hypercall interface is limited to 16bit PCI segment
+		 * values.
+		 */
+		dev_info(&dev->dev,
+			 "unable to notify Xen of device reset: invalid PCI segment\n");
+		return 0;
+	}
+
 	return HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_reset, &device);
 }
 EXPORT_SYMBOL_GPL(xen_reset_device);
diff --git a/drivers/xen/pcpu.c b/drivers/xen/pcpu.c
index c63f317e3df3..093ad4a08672 100644
--- a/drivers/xen/pcpu.c
+++ b/drivers/xen/pcpu.c
@@ -105,7 +105,7 @@ static ssize_t online_show(struct device *dev,
 	return sprintf(buf, "%u\n", !!(cpu->flags & XEN_PCPU_FLAGS_ONLINE));
 }
 
-static ssize_t __ref online_store(struct device *dev,
+static ssize_t online_store(struct device *dev,
 				  struct device_attribute *attr,
 				  const char *buf, size_t count)
 {
diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c
index 544d3f9010b9..1db82da56db6 100644
--- a/drivers/xen/platform-pci.c
+++ b/drivers/xen/platform-pci.c
@@ -26,6 +26,8 @@
 
 #define DRV_NAME    "xen-platform-pci"
 
+#define PCI_DEVICE_ID_XEN_PLATFORM_XS61	0x0002
+
 static unsigned long platform_mmio;
 static unsigned long platform_mmio_alloc;
 static unsigned long platform_mmiolen;
@@ -174,6 +176,8 @@ pci_out:
 static const struct pci_device_id platform_pci_tbl[] = {
 	{PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+	{PCI_VENDOR_ID_XEN, PCI_DEVICE_ID_XEN_PLATFORM_XS61,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
 	{0,}
 };
 
diff --git a/drivers/xen/pvcalls-front.c b/drivers/xen/pvcalls-front.c
index b72ee9379d77..4926d4badc57 100644
--- a/drivers/xen/pvcalls-front.c
+++ b/drivers/xen/pvcalls-front.c
@@ -341,6 +341,7 @@ int pvcalls_front_socket(struct socket *sock)
 	pvcalls_exit();
 	return ret;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_socket);
 
 static void free_active_ring(struct sock_mapping *map)
 {
@@ -486,6 +487,7 @@ int pvcalls_front_connect(struct socket *sock, struct sockaddr *addr,
 	pvcalls_exit_sock(sock);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_connect);
 
 static int __write_ring(struct pvcalls_data_intf *intf,
 			struct pvcalls_data *data,
@@ -581,6 +583,7 @@ again:
 	pvcalls_exit_sock(sock);
 	return tot_sent;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_sendmsg);
 
 static int __read_ring(struct pvcalls_data_intf *intf,
 		       struct pvcalls_data *data,
@@ -666,6 +669,7 @@ int pvcalls_front_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
 	pvcalls_exit_sock(sock);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_recvmsg);
 
 int pvcalls_front_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 {
@@ -719,6 +723,7 @@ int pvcalls_front_bind(struct socket *sock, struct sockaddr *addr, int addr_len)
 	pvcalls_exit_sock(sock);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_bind);
 
 int pvcalls_front_listen(struct socket *sock, int backlog)
 {
@@ -768,8 +773,10 @@ int pvcalls_front_listen(struct socket *sock, int backlog)
 	pvcalls_exit_sock(sock);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_listen);
 
-int pvcalls_front_accept(struct socket *sock, struct socket *newsock, int flags)
+int pvcalls_front_accept(struct socket *sock, struct socket *newsock,
+			 struct proto_accept_arg *arg)
 {
 	struct pvcalls_bedata *bedata;
 	struct sock_mapping *map;
@@ -788,7 +795,7 @@ int pvcalls_front_accept(struct socket *sock, struct socket *newsock, int flags)
 		return -EINVAL;
 	}
 
-	nonblock = flags & SOCK_NONBLOCK;
+	nonblock = arg->flags & SOCK_NONBLOCK;
 	/*
 	 * Backend only supports 1 inflight accept request, will return
 	 * errors for the others
@@ -904,6 +911,7 @@ received:
 	pvcalls_exit_sock(sock);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_accept);
 
 static __poll_t pvcalls_front_poll_passive(struct file *file,
 					       struct pvcalls_bedata *bedata,
@@ -1004,6 +1012,7 @@ __poll_t pvcalls_front_poll(struct file *file, struct socket *sock,
 	pvcalls_exit_sock(sock);
 	return ret;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_poll);
 
 int pvcalls_front_release(struct socket *sock)
 {
@@ -1087,6 +1096,7 @@ int pvcalls_front_release(struct socket *sock)
 	pvcalls_exit();
 	return 0;
 }
+EXPORT_SYMBOL_GPL(pvcalls_front_release);
 
 static const struct xenbus_device_id pvcalls_front_ids[] = {
 	{ "pvcalls" },
diff --git a/drivers/xen/pvcalls-front.h b/drivers/xen/pvcalls-front.h
index f694ad77379f..881ef14660bc 100644
--- a/drivers/xen/pvcalls-front.h
+++ b/drivers/xen/pvcalls-front.h
@@ -12,7 +12,7 @@ int pvcalls_front_bind(struct socket *sock,
 int pvcalls_front_listen(struct socket *sock, int backlog);
 int pvcalls_front_accept(struct socket *sock,
 			 struct socket *newsock,
-			 int flags);
+			 struct proto_accept_arg *arg);
 int pvcalls_front_sendmsg(struct socket *sock,
 			  struct msghdr *msg,
 			  size_t len);
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 26c62e0d34e9..da1a7d3d377c 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -113,7 +113,7 @@ static struct io_tlb_pool *xen_swiotlb_find_pool(struct device *dev,
 }
 
 #ifdef CONFIG_X86
-int xen_swiotlb_fixup(void *buf, unsigned long nslabs)
+int __init xen_swiotlb_fixup(void *buf, unsigned long nslabs)
 {
 	int rc;
 	unsigned int order = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT);
@@ -217,6 +217,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
 	 * buffering it.
 	 */
 	if (dma_capable(dev, dev_addr, size, true) &&
+	    !dma_kmalloc_needs_bounce(dev, size, dir) &&
 	    !range_straddles_page_boundary(phys, size) &&
 		!xen_arch_need_swiotlb(dev, phys, dev_addr) &&
 		!is_swiotlb_force_bounce(dev))
@@ -425,4 +426,5 @@ const struct dma_map_ops xen_swiotlb_dma_ops = {
 	.alloc_pages_op = dma_common_alloc_pages,
 	.free_pages = dma_common_free_pages,
 	.max_mapping_size = swiotlb_max_mapping_size,
+	.map_resource = dma_direct_map_resource,
 };
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index b616b7768c3b..5c2f829d5b0b 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -262,26 +262,6 @@ struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 	return found_dev;
 }
 
-struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
-				    struct pci_dev *dev)
-{
-	struct pcistub_device *psdev;
-	struct pci_dev *found_dev = NULL;
-	unsigned long flags;
-
-	spin_lock_irqsave(&pcistub_devices_lock, flags);
-
-	list_for_each_entry(psdev, &pcistub_devices, dev_list) {
-		if (psdev->dev == dev) {
-			found_dev = pcistub_device_get_pci_dev(pdev, psdev);
-			break;
-		}
-	}
-
-	spin_unlock_irqrestore(&pcistub_devices_lock, flags);
-	return found_dev;
-}
-
 /*
  * Called when:
  *  - XenBus state has been reconfigure (pci unplug). See xen_pcibk_remove_device
diff --git a/drivers/xen/xen-pciback/pciback.h b/drivers/xen/xen-pciback/pciback.h
index f9599ed2f2e2..b786c1f74f85 100644
--- a/drivers/xen/xen-pciback/pciback.h
+++ b/drivers/xen/xen-pciback/pciback.h
@@ -67,8 +67,6 @@ extern struct list_head xen_pcibk_quirks;
 struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 					    int domain, int bus,
 					    int slot, int func);
-struct pci_dev *pcistub_get_pci_dev(struct xen_pcibk_device *pdev,
-				    struct pci_dev *dev);
 void pcistub_put_pci_dev(struct pci_dev *dev);
 
 static inline bool xen_pcibk_pv_support(void)
diff --git a/drivers/xen/xenbus/xenbus.h b/drivers/xen/xenbus/xenbus.h
index 13821e7e825e..9ac0427724a3 100644
--- a/drivers/xen/xenbus/xenbus.h
+++ b/drivers/xen/xenbus/xenbus.h
@@ -77,6 +77,7 @@ enum xb_req_state {
 struct xb_req_data {
 	struct list_head list;
 	wait_queue_head_t wq;
+	struct kref kref;
 	struct xsd_sockmsg msg;
 	uint32_t caller_req_id;
 	enum xsd_sockmsg_type type;
@@ -103,6 +104,7 @@ int xb_init_comms(void);
 void xb_deinit_comms(void);
 int xs_watch_msg(struct xs_watch_event *event);
 void xs_request_exit(struct xb_req_data *req);
+void xs_free_req(struct kref *kref);
 
 int xenbus_match(struct device *_dev, const struct device_driver *_drv);
 int xenbus_dev_probe(struct device *_dev);
diff --git a/drivers/xen/xenbus/xenbus_comms.c b/drivers/xen/xenbus/xenbus_comms.c
index e5fda0256feb..82df2da1b880 100644
--- a/drivers/xen/xenbus/xenbus_comms.c
+++ b/drivers/xen/xenbus/xenbus_comms.c
@@ -309,8 +309,8 @@ static int process_msg(void)
 			virt_wmb();
 			req->state = xb_req_state_got_reply;
 			req->cb(req);
-		} else
-			kfree(req);
+		}
+		kref_put(&req->kref, xs_free_req);
 	}
 
 	mutex_unlock(&xs_response_mutex);
@@ -386,14 +386,13 @@ static int process_writes(void)
 	state.req->msg.type = XS_ERROR;
 	state.req->err = err;
 	list_del(&state.req->list);
-	if (state.req->state == xb_req_state_aborted)
-		kfree(state.req);
-	else {
+	if (state.req->state != xb_req_state_aborted) {
 		/* write err, then update state */
 		virt_wmb();
 		state.req->state = xb_req_state_got_reply;
 		wake_up(&state.req->wq);
 	}
+	kref_put(&state.req->kref, xs_free_req);
 
 	mutex_unlock(&xb_write_mutex);
 
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 46f8916597e5..f5c21ba64df5 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -406,7 +406,7 @@ void xenbus_dev_queue_reply(struct xb_req_data *req)
 	mutex_unlock(&u->reply_mutex);
 
 	kfree(req->body);
-	kfree(req);
+	kref_put(&req->kref, xs_free_req);
 
 	kref_put(&u->kref, xenbus_file_free);
 
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 6d32ffb01136..86fe6e779056 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -966,9 +966,15 @@ static int __init xenbus_init(void)
 	if (xen_pv_domain())
 		xen_store_domain_type = XS_PV;
 	if (xen_hvm_domain())
+	{
 		xen_store_domain_type = XS_HVM;
-	if (xen_hvm_domain() && xen_initial_domain())
-		xen_store_domain_type = XS_LOCAL;
+		err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
+		if (err)
+			goto out_error;
+		xen_store_evtchn = (int)v;
+		if (!v && xen_initial_domain())
+			xen_store_domain_type = XS_LOCAL;
+	}
 	if (xen_pv_domain() && !xen_start_info->store_evtchn)
 		xen_store_domain_type = XS_LOCAL;
 	if (xen_pv_domain() && xen_start_info->store_evtchn)
@@ -987,10 +993,6 @@ static int __init xenbus_init(void)
 		xen_store_interface = gfn_to_virt(xen_store_gfn);
 		break;
 	case XS_HVM:
-		err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
-		if (err)
-			goto out_error;
-		xen_store_evtchn = (int)v;
 		err = hvm_get_parameter(HVM_PARAM_STORE_PFN, &v);
 		if (err)
 			goto out_error;
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index fcb335bb7b18..6d1819269cbe 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -513,4 +513,5 @@ static int __init boot_wait_for_devices(void)
 late_initcall(boot_wait_for_devices);
 #endif
 
+MODULE_DESCRIPTION("Xen PV-device frontend support");
 MODULE_LICENSE("GPL");
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index d32c726f7a12..dcf9182c8451 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -112,6 +112,12 @@ static void xs_suspend_exit(void)
 	wake_up_all(&xs_state_enter_wq);
 }
 
+void xs_free_req(struct kref *kref)
+{
+	struct xb_req_data *req = container_of(kref, struct xb_req_data, kref);
+	kfree(req);
+}
+
 static uint32_t xs_request_enter(struct xb_req_data *req)
 {
 	uint32_t rq_id;
@@ -237,6 +243,12 @@ static void xs_send(struct xb_req_data *req, struct xsd_sockmsg *msg)
 	req->caller_req_id = req->msg.req_id;
 	req->msg.req_id = xs_request_enter(req);
 
+	/*
+	 * Take 2nd ref.  One for this thread, and the second for the
+	 * xenbus_thread.
+	 */
+	kref_get(&req->kref);
+
 	mutex_lock(&xb_write_mutex);
 	list_add_tail(&req->list, &xb_write_list);
 	notify = list_is_singular(&xb_write_list);
@@ -261,8 +273,8 @@ static void *xs_wait_for_reply(struct xb_req_data *req, struct xsd_sockmsg *msg)
 	if (req->state == xb_req_state_queued ||
 	    req->state == xb_req_state_wait_reply)
 		req->state = xb_req_state_aborted;
-	else
-		kfree(req);
+
+	kref_put(&req->kref, xs_free_req);
 	mutex_unlock(&xb_write_mutex);
 
 	return ret;
@@ -291,6 +303,7 @@ int xenbus_dev_request_and_reply(struct xsd_sockmsg *msg, void *par)
 	req->cb = xenbus_dev_queue_reply;
 	req->par = par;
 	req->user_req = true;
+	kref_init(&req->kref);
 
 	xs_send(req, msg);
 
@@ -319,6 +332,7 @@ static void *xs_talkv(struct xenbus_transaction t,
 	req->num_vecs = num_vecs;
 	req->cb = xs_wake_up;
 	req->user_req = false;
+	kref_init(&req->kref);
 
 	msg.req_id = 0;
 	msg.tx_id = t.id;
diff --git a/drivers/xen/xenfs/xensyms.c b/drivers/xen/xenfs/xensyms.c
index b799bc759c15..088b7f02c358 100644
--- a/drivers/xen/xenfs/xensyms.c
+++ b/drivers/xen/xenfs/xensyms.c
@@ -48,7 +48,7 @@ static int xensyms_next_sym(struct xensyms *xs)
 			return -ENOMEM;
 
 		set_xen_guest_handle(symdata->name, xs->name);
-		symdata->symnum--; /* Rewind */
+		symdata->symnum = symnum; /* Rewind */
 
 		ret = HYPERVISOR_platform_op(&xs->op);
 		if (ret < 0)
@@ -78,7 +78,7 @@ static void *xensyms_next(struct seq_file *m, void *p, loff_t *pos)
 {
 	struct xensyms *xs = m->private;
 
-	xs->op.u.symdata.symnum = ++(*pos);
+	*pos = xs->op.u.symdata.symnum;
 
 	if (xensyms_next_sym(xs))
 		return NULL;