Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen updates from Konrad Rzeszutek Wilk:
 - Add necessary infrastructure to make balloon driver work under ARM.
 - Add /dev/xen/privcmd interfaces to work with ARM and PVH.
 - Improve Xen PCIBack wild-card parsing.
 - Add Xen ACPI PAD (Processor Aggregator) support - so can offline/
   online sockets depending on the power consumption.
 - PVHVM + kexec = use an E820_RESV region for the shared region so we
   don't overwrite said region during kexec reboot.
 - Cleanups, compile fixes.

Fix up some trivial conflicts due to the balloon driver now working on
ARM, and there were changes next to the previous work-arounds that are
now gone.

* tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/PVonHVM: fix compile warning in init_hvm_pv_info
  xen: arm: implement remap interfaces needed for privcmd mappings.
  xen: correctly use xen_pfn_t in remap_domain_mfn_range.
  xen: arm: enable balloon driver
  xen: balloon: allow PVMMU interfaces to be compiled out
  xen: privcmd: support autotranslated physmap guests.
  xen: add pages parameter to xen_remap_domain_mfn_range
  xen/acpi: Move the xen_running_on_version_or_later function.
  xen/xenbus: Remove duplicate inclusion of asm/xen/hypervisor.h
  xen/acpi: Fix compile error by missing decleration for xen_domain.
  xen/acpi: revert pad config check in xen_check_mwait
  xen/acpi: ACPI PAD driver
  xen-pciback: reject out of range inputs
  xen-pciback: simplify and tighten parsing of device IDs
  xen PVonHVM: use E820_Reserved area for shared_info

7 files changed, 326 insertions, 62 deletions

diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index 126d8ce..cabfa97 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -206,4 +206,7 @@ config XEN_MCE_LOG
 	  Allow kernel fetching MCE error from Xen platform and
 	  converting it into Linux mcelog format for mcelog tools
 
+config XEN_HAVE_PVMMU
+       bool
+
 endmenu
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index 7435470..fb213cf 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -1,9 +1,9 @@
 ifneq ($(CONFIG_ARM),y)
-obj-y	+= manage.o balloon.o
+obj-y	+= manage.o
 obj-$(CONFIG_HOTPLUG_CPU)		+= cpu_hotplug.o
 endif
 obj-$(CONFIG_X86)			+= fallback.o
-obj-y	+= grant-table.o features.o events.o
+obj-y	+= grant-table.o features.o events.o balloon.o
 obj-y	+= xenbus/
 
 nostackp := $(call cc-option, -fno-stack-protector)
@@ -11,7 +11,8 @@ CFLAGS_features.o			:= $(nostackp)
 
 dom0-$(CONFIG_PCI) += pci.o
 dom0-$(CONFIG_USB_SUPPORT) += dbgp.o
-dom0-$(CONFIG_ACPI) += acpi.o
+dom0-$(CONFIG_ACPI) += acpi.o $(xen-pad-y)
+xen-pad-$(CONFIG_X86) += xen-acpi-pad.o
 dom0-$(CONFIG_X86) += pcpu.o
 obj-$(CONFIG_XEN_DOM0)			+= $(dom0-y)
 obj-$(CONFIG_BLOCK)			+= biomerge.o
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index d6886d9..a56776d 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -359,6 +359,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
 
 		set_phys_to_machine(pfn, frame_list[i]);
 
+#ifdef CONFIG_XEN_HAVE_PVMMU
 		/* Link back into the page tables if not highmem. */
 		if (xen_pv_domain() && !PageHighMem(page)) {
 			int ret;
@@ -368,6 +369,7 @@ static enum bp_state increase_reservation(unsigned long nr_pages)
 				0);
 			BUG_ON(ret);
 		}
+#endif
 
 		/* Relinquish the page back to the allocator. */
 		ClearPageReserved(page);
@@ -416,13 +418,14 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 
 		scrub_page(page);
 
+#ifdef CONFIG_XEN_HAVE_PVMMU
 		if (xen_pv_domain() && !PageHighMem(page)) {
 			ret = HYPERVISOR_update_va_mapping(
 				(unsigned long)__va(pfn << PAGE_SHIFT),
 				__pte_ma(0), 0);
 			BUG_ON(ret);
 		}
-
+#endif
 	}
 
 	/* Ensure that ballooned highmem pages don't have kmaps. */
diff --git a/drivers/xen/privcmd.c b/drivers/xen/privcmd.c
index 71f5c45..0bbbccbb 100644
--- a/drivers/xen/privcmd.c
+++ b/drivers/xen/privcmd.c
@@ -33,11 +33,14 @@
 #include <xen/features.h>
 #include <xen/page.h>
 #include <xen/xen-ops.h>
+#include <xen/balloon.h>
 
 #include "privcmd.h"
 
 MODULE_LICENSE("GPL");
 
+#define PRIV_VMA_LOCKED ((void *)1)
+
 #ifndef HAVE_ARCH_PRIVCMD_MMAP
 static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma);
 #endif
@@ -178,7 +181,7 @@ static int mmap_mfn_range(void *data, void *state)
 					msg->va & PAGE_MASK,
 					msg->mfn, msg->npages,
 					vma->vm_page_prot,
-					st->domain);
+					st->domain, NULL);
 	if (rc < 0)
 		return rc;
 
@@ -199,6 +202,10 @@ static long privcmd_ioctl_mmap(void __user *udata)
 	if (!xen_initial_domain())
 		return -EPERM;
 
+	/* We only support privcmd_ioctl_mmap_batch for auto translated. */
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		return -ENOSYS;
+
 	if (copy_from_user(&mmapcmd, udata, sizeof(mmapcmd)))
 		return -EFAULT;
 
@@ -246,6 +253,7 @@ struct mmap_batch_state {
 	domid_t domain;
 	unsigned long va;
 	struct vm_area_struct *vma;
+	int index;
 	/* A tristate:
 	 *      0 for no errors
 	 *      1 if at least one error has happened (and no
@@ -260,14 +268,24 @@ struct mmap_batch_state {
 	xen_pfn_t __user *user_mfn;
 };
 
+/* auto translated dom0 note: if domU being created is PV, then mfn is
+ * mfn(addr on bus). If it's auto xlated, then mfn is pfn (input to HAP).
+ */
 static int mmap_batch_fn(void *data, void *state)
 {
 	xen_pfn_t *mfnp = data;
 	struct mmap_batch_state *st = state;
+	struct vm_area_struct *vma = st->vma;
+	struct page **pages = vma->vm_private_data;
+	struct page *cur_page = NULL;
 	int ret;
 
+	if (xen_feature(XENFEAT_auto_translated_physmap))
+		cur_page = pages[st->index++];
+
 	ret = xen_remap_domain_mfn_range(st->vma, st->va & PAGE_MASK, *mfnp, 1,
-					 st->vma->vm_page_prot, st->domain);
+					 st->vma->vm_page_prot, st->domain,
+					 &cur_page);
 
 	/* Store error code for second pass. */
 	*(st->err++) = ret;
@@ -303,6 +321,32 @@ static int mmap_return_errors_v1(void *data, void *state)
 	return __put_user(*mfnp, st->user_mfn++);
 }
 
+/* Allocate pfns that are then mapped with gmfns from foreign domid. Update
+ * the vma with the page info to use later.
+ * Returns: 0 if success, otherwise -errno
+ */
+static int alloc_empty_pages(struct vm_area_struct *vma, int numpgs)
+{
+	int rc;
+	struct page **pages;
+
+	pages = kcalloc(numpgs, sizeof(pages[0]), GFP_KERNEL);
+	if (pages == NULL)
+		return -ENOMEM;
+
+	rc = alloc_xenballooned_pages(numpgs, pages, 0);
+	if (rc != 0) {
+		pr_warn("%s Could not alloc %d pfns rc:%d\n", __func__,
+			numpgs, rc);
+		kfree(pages);
+		return -ENOMEM;
+	}
+	BUG_ON(vma->vm_private_data != PRIV_VMA_LOCKED);
+	vma->vm_private_data = pages;
+
+	return 0;
+}
+
 static struct vm_operations_struct privcmd_vm_ops;
 
 static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
@@ -370,10 +414,18 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 		ret = -EINVAL;
 		goto out;
 	}
+	if (xen_feature(XENFEAT_auto_translated_physmap)) {
+		ret = alloc_empty_pages(vma, m.num);
+		if (ret < 0) {
+			up_write(&mm->mmap_sem);
+			goto out;
+		}
+	}
 
 	state.domain        = m.dom;
 	state.vma           = vma;
 	state.va            = m.addr;
+	state.index         = 0;
 	state.global_error  = 0;
 	state.err           = err_array;
 
@@ -442,6 +494,19 @@ static long privcmd_ioctl(struct file *file,
 	return ret;
 }
 
+static void privcmd_close(struct vm_area_struct *vma)
+{
+	struct page **pages = vma->vm_private_data;
+	int numpgs = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+
+	if (!xen_feature(XENFEAT_auto_translated_physmap || !numpgs || !pages))
+		return;
+
+	xen_unmap_domain_mfn_range(vma, numpgs, pages);
+	free_xenballooned_pages(numpgs, pages);
+	kfree(pages);
+}
+
 static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 {
 	printk(KERN_DEBUG "privcmd_fault: vma=%p %lx-%lx, pgoff=%lx, uv=%p\n",
@@ -452,6 +517,7 @@ static int privcmd_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 }
 
 static struct vm_operations_struct privcmd_vm_ops = {
+	.close = privcmd_close,
 	.fault = privcmd_fault
 };
 
@@ -469,7 +535,7 @@ static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
 
 static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma)
 {
-	return (xchg(&vma->vm_private_data, (void *)1) == NULL);
+	return !cmpxchg(&vma->vm_private_data, NULL, PRIV_VMA_LOCKED);
 }
 
 const struct file_operations xen_privcmd_fops = {
diff --git a/drivers/xen/xen-acpi-pad.c b/drivers/xen/xen-acpi-pad.c
new file mode 100644
index 0000000..da39191
--- /dev/null
+++ b/drivers/xen/xen-acpi-pad.c
@@ -0,0 +1,182 @@
+/*
+ * xen-acpi-pad.c - Xen pad interface
+ *
+ * Copyright (c) 2012, Intel Corporation.
+ *    Author: Liu, Jinsong <jinsong.liu@intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+#include <asm/xen/hypercall.h>
+#include <xen/interface/version.h>
+#include <xen/xen-ops.h>
+
+#define ACPI_PROCESSOR_AGGREGATOR_CLASS	"acpi_pad"
+#define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator"
+#define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80
+static DEFINE_MUTEX(xen_cpu_lock);
+
+static int xen_acpi_pad_idle_cpus(unsigned int idle_nums)
+{
+	struct xen_platform_op op;
+
+	op.cmd = XENPF_core_parking;
+	op.u.core_parking.type = XEN_CORE_PARKING_SET;
+	op.u.core_parking.idle_nums = idle_nums;
+
+	return HYPERVISOR_dom0_op(&op);
+}
+
+static int xen_acpi_pad_idle_cpus_num(void)
+{
+	struct xen_platform_op op;
+
+	op.cmd = XENPF_core_parking;
+	op.u.core_parking.type = XEN_CORE_PARKING_GET;
+
+	return HYPERVISOR_dom0_op(&op)
+	       ?: op.u.core_parking.idle_nums;
+}
+
+/*
+ * Query firmware how many CPUs should be idle
+ * return -1 on failure
+ */
+static int acpi_pad_pur(acpi_handle handle)
+{
+	struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL};
+	union acpi_object *package;
+	int num = -1;
+
+	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_PUR", NULL, &buffer)))
+		return num;
+
+	if (!buffer.length || !buffer.pointer)
+		return num;
+
+	package = buffer.pointer;
+
+	if (package->type == ACPI_TYPE_PACKAGE &&
+		package->package.count == 2 &&
+		package->package.elements[0].integer.value == 1) /* rev 1 */
+		num = package->package.elements[1].integer.value;
+
+	kfree(buffer.pointer);
+	return num;
+}
+
+/* Notify firmware how many CPUs are idle */
+static void acpi_pad_ost(acpi_handle handle, int stat,
+	uint32_t idle_nums)
+{
+	union acpi_object params[3] = {
+		{.type = ACPI_TYPE_INTEGER,},
+		{.type = ACPI_TYPE_INTEGER,},
+		{.type = ACPI_TYPE_BUFFER,},
+	};
+	struct acpi_object_list arg_list = {3, params};
+
+	params[0].integer.value = ACPI_PROCESSOR_AGGREGATOR_NOTIFY;
+	params[1].integer.value =  stat;
+	params[2].buffer.length = 4;
+	params[2].buffer.pointer = (void *)&idle_nums;
+	acpi_evaluate_object(handle, "_OST", &arg_list, NULL);
+}
+
+static void acpi_pad_handle_notify(acpi_handle handle)
+{
+	int idle_nums;
+
+	mutex_lock(&xen_cpu_lock);
+	idle_nums = acpi_pad_pur(handle);
+	if (idle_nums < 0) {
+		mutex_unlock(&xen_cpu_lock);
+		return;
+	}
+
+	idle_nums = xen_acpi_pad_idle_cpus(idle_nums)
+		    ?: xen_acpi_pad_idle_cpus_num();
+	if (idle_nums >= 0)
+		acpi_pad_ost(handle, 0, idle_nums);
+	mutex_unlock(&xen_cpu_lock);
+}
+
+static void acpi_pad_notify(acpi_handle handle, u32 event,
+	void *data)
+{
+	switch (event) {
+	case ACPI_PROCESSOR_AGGREGATOR_NOTIFY:
+		acpi_pad_handle_notify(handle);
+		break;
+	default:
+		pr_warn("Unsupported event [0x%x]\n", event);
+		break;
+	}
+}
+
+static int acpi_pad_add(struct acpi_device *device)
+{
+	acpi_status status;
+
+	strcpy(acpi_device_name(device), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME);
+	strcpy(acpi_device_class(device), ACPI_PROCESSOR_AGGREGATOR_CLASS);
+
+	status = acpi_install_notify_handler(device->handle,
+		ACPI_DEVICE_NOTIFY, acpi_pad_notify, device);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	return 0;
+}
+
+static int acpi_pad_remove(struct acpi_device *device,
+	int type)
+{
+	mutex_lock(&xen_cpu_lock);
+	xen_acpi_pad_idle_cpus(0);
+	mutex_unlock(&xen_cpu_lock);
+
+	acpi_remove_notify_handler(device->handle,
+		ACPI_DEVICE_NOTIFY, acpi_pad_notify);
+	return 0;
+}
+
+static const struct acpi_device_id pad_device_ids[] = {
+	{"ACPI000C", 0},
+	{"", 0},
+};
+
+static struct acpi_driver acpi_pad_driver = {
+	.name = "processor_aggregator",
+	.class = ACPI_PROCESSOR_AGGREGATOR_CLASS,
+	.ids = pad_device_ids,
+	.ops = {
+		.add = acpi_pad_add,
+		.remove = acpi_pad_remove,
+	},
+};
+
+static int __init xen_acpi_pad_init(void)
+{
+	/* Only DOM0 is responsible for Xen acpi pad */
+	if (!xen_initial_domain())
+		return -ENODEV;
+
+	/* Only Xen4.2 or later support Xen acpi pad */
+	if (!xen_running_on_version_or_later(4, 2))
+		return -ENODEV;
+
+	return acpi_bus_register_driver(&acpi_pad_driver);
+}
+subsys_initcall(xen_acpi_pad_init);
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 68dcc59..cd50d25 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -142,7 +142,8 @@ static struct pcistub_device *pcistub_device_find(int domain, int bus,
 		if (psdev->dev != NULL
 		    && domain == pci_domain_nr(psdev->dev->bus)
 		    && bus == psdev->dev->bus->number
-		    && PCI_DEVFN(slot, func) == psdev->dev->devfn) {
+		    && slot == PCI_SLOT(psdev->dev->devfn)
+		    && func == PCI_FUNC(psdev->dev->devfn)) {
 			pcistub_device_get(psdev);
 			goto out;
 		}
@@ -191,7 +192,8 @@ struct pci_dev *pcistub_get_pci_dev_by_slot(struct xen_pcibk_device *pdev,
 		if (psdev->dev != NULL
 		    && domain == pci_domain_nr(psdev->dev->bus)
 		    && bus == psdev->dev->bus->number
-		    && PCI_DEVFN(slot, func) == psdev->dev->devfn) {
+		    && slot == PCI_SLOT(psdev->dev->devfn)
+		    && func == PCI_FUNC(psdev->dev->devfn)) {
 			found_dev = pcistub_device_get_pci_dev(pdev, psdev);
 			break;
 		}
@@ -897,42 +899,35 @@ static struct pci_driver xen_pcibk_pci_driver = {
 static inline int str_to_slot(const char *buf, int *domain, int *bus,
 			      int *slot, int *func)
 {
-	int err;
-	char wc = '*';
+	int parsed = 0;
 
-	err = sscanf(buf, " %x:%x:%x.%x", domain, bus, slot, func);
-	switch (err) {
+	switch (sscanf(buf, " %x:%x:%x.%x %n", domain, bus, slot, func,
+		       &parsed)) {
 	case 3:
 		*func = -1;
-		err = sscanf(buf, " %x:%x:%x.%c", domain, bus, slot, &wc);
+		sscanf(buf, " %x:%x:%x.* %n", domain, bus, slot, &parsed);
 		break;
 	case 2:
 		*slot = *func = -1;
-		err = sscanf(buf, " %x:%x:*.%c", domain, bus, &wc);
-		if (err >= 2)
-			++err;
+		sscanf(buf, " %x:%x:*.* %n", domain, bus, &parsed);
 		break;
 	}
-	if (err == 4 && wc == '*')
+	if (parsed && !buf[parsed])
 		return 0;
-	else if (err < 0)
-		return -EINVAL;
 
 	/* try again without domain */
 	*domain = 0;
-	wc = '*';
-	err = sscanf(buf, " %x:%x.%x", bus, slot, func);
-	switch (err) {
+	switch (sscanf(buf, " %x:%x.%x %n", bus, slot, func, &parsed)) {
 	case 2:
 		*func = -1;
-		err = sscanf(buf, " %x:%x.%c", bus, slot, &wc);
+		sscanf(buf, " %x:%x.* %n", bus, slot, &parsed);
 		break;
 	case 1:
 		*slot = *func = -1;
-		err = sscanf(buf, " %x:*.%c", bus, &wc) + 1;
+		sscanf(buf, " %x:*.* %n", bus, &parsed);
 		break;
 	}
-	if (err == 3 && wc == '*')
+	if (parsed && !buf[parsed])
 		return 0;
 
 	return -EINVAL;
@@ -941,13 +936,20 @@ static inline int str_to_slot(const char *buf, int *domain, int *bus,
 static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
 			       *slot, int *func, int *reg, int *size, int *mask)
 {
-	int err;
+	int parsed = 0;
 
-	err =
-	    sscanf(buf, " %04x:%02x:%02x.%d-%08x:%1x:%08x", domain, bus, slot,
-		   func, reg, size, mask);
-	if (err == 7)
+	sscanf(buf, " %x:%x:%x.%x-%x:%x:%x %n", domain, bus, slot, func,
+	       reg, size, mask, &parsed);
+	if (parsed && !buf[parsed])
 		return 0;
+
+	/* try again without domain */
+	*domain = 0;
+	sscanf(buf, " %x:%x.%x-%x:%x:%x %n", bus, slot, func, reg, size,
+	       mask, &parsed);
+	if (parsed && !buf[parsed])
+		return 0;
+
 	return -EINVAL;
 }
 
@@ -955,7 +957,7 @@ static int pcistub_device_id_add(int domain, int bus, int slot, int func)
 {
 	struct pcistub_device_id *pci_dev_id;
 	unsigned long flags;
-	int rc = 0;
+	int rc = 0, devfn = PCI_DEVFN(slot, func);
 
 	if (slot < 0) {
 		for (slot = 0; !rc && slot < 32; ++slot)
@@ -969,13 +971,24 @@ static int pcistub_device_id_add(int domain, int bus, int slot, int func)
 		return rc;
 	}
 
+	if ((
+#if !defined(MODULE) /* pci_domains_supported is not being exported */ \
+    || !defined(CONFIG_PCI_DOMAINS)
+	     !pci_domains_supported ? domain :
+#endif
+	     domain < 0 || domain > 0xffff)
+	    || bus < 0 || bus > 0xff
+	    || PCI_SLOT(devfn) != slot
+	    || PCI_FUNC(devfn) != func)
+		return -EINVAL;
+
 	pci_dev_id = kmalloc(sizeof(*pci_dev_id), GFP_KERNEL);
 	if (!pci_dev_id)
 		return -ENOMEM;
 
 	pci_dev_id->domain = domain;
 	pci_dev_id->bus = bus;
-	pci_dev_id->devfn = PCI_DEVFN(slot, func);
+	pci_dev_id->devfn = devfn;
 
 	pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%d\n",
 		 domain, bus, slot, func);
@@ -1016,14 +1029,18 @@ static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
 	return err;
 }
 
-static int pcistub_reg_add(int domain, int bus, int slot, int func, int reg,
-			   int size, int mask)
+static int pcistub_reg_add(int domain, int bus, int slot, int func,
+			   unsigned int reg, unsigned int size,
+			   unsigned int mask)
 {
 	int err = 0;
 	struct pcistub_device *psdev;
 	struct pci_dev *dev;
 	struct config_field *field;
 
+	if (reg > 0xfff || (size < 4 && (mask >> (size * 8))))
+		return -EINVAL;
+
 	psdev = pcistub_device_find(domain, bus, slot, func);
 	if (!psdev) {
 		err = -ENODEV;
@@ -1254,13 +1271,11 @@ static ssize_t permissive_add(struct device_driver *drv, const char *buf,
 	int err;
 	struct pcistub_device *psdev;
 	struct xen_pcibk_dev_data *dev_data;
+
 	err = str_to_slot(buf, &domain, &bus, &slot, &func);
 	if (err)
 		goto out;
-	if (slot < 0 || func < 0) {
-		err = -EINVAL;
-		goto out;
-	}
+
 	psdev = pcistub_device_find(domain, bus, slot, func);
 	if (!psdev) {
 		err = -ENODEV;
@@ -1339,8 +1354,6 @@ static int __init pcistub_init(void)
 
 	if (pci_devs_to_hide && *pci_devs_to_hide) {
 		do {
-			char wc = '*';
-
 			parsed = 0;
 
 			err = sscanf(pci_devs_to_hide + pos,
@@ -1349,51 +1362,48 @@ static int __init pcistub_init(void)
 			switch (err) {
 			case 3:
 				func = -1;
-				err = sscanf(pci_devs_to_hide + pos,
-					     " (%x:%x:%x.%c) %n",
-					     &domain, &bus, &slot, &wc,
-					     &parsed);
+				sscanf(pci_devs_to_hide + pos,
+				       " (%x:%x:%x.*) %n",
+				       &domain, &bus, &slot, &parsed);
 				break;
 			case 2:
 				slot = func = -1;
-				err = sscanf(pci_devs_to_hide + pos,
-					     " (%x:%x:*.%c) %n",
-					     &domain, &bus, &wc, &parsed) + 1;
+				sscanf(pci_devs_to_hide + pos,
+				       " (%x:%x:*.*) %n",
+				       &domain, &bus, &parsed);
 				break;
 			}
 
-			if (err != 4 || wc != '*') {
+			if (!parsed) {
 				domain = 0;
-				wc = '*';
 				err = sscanf(pci_devs_to_hide + pos,
 					     " (%x:%x.%x) %n",
 					     &bus, &slot, &func, &parsed);
 				switch (err) {
 				case 2:
 					func = -1;
-					err = sscanf(pci_devs_to_hide + pos,
-						     " (%x:%x.%c) %n",
-						     &bus, &slot, &wc,
-						     &parsed);
+					sscanf(pci_devs_to_hide + pos,
+					       " (%x:%x.*) %n",
+					       &bus, &slot, &parsed);
 					break;
 				case 1:
 					slot = func = -1;
-					err = sscanf(pci_devs_to_hide + pos,
-						     " (%x:*.%c) %n",
-						     &bus, &wc, &parsed) + 1;
+					sscanf(pci_devs_to_hide + pos,
+					       " (%x:*.*) %n",
+					       &bus, &parsed);
 					break;
 				}
-				if (err != 3 || wc != '*')
-					goto parse_error;
 			}
 
+			if (parsed <= 0)
+				goto parse_error;
+
 			err = pcistub_device_id_add(domain, bus, slot, func);
 			if (err)
 				goto out;
 
-			/* if parsed<=0, we've reached the end of the string */
 			pos += parsed;
-		} while (parsed > 0 && pci_devs_to_hide[pos]);
+		} while (pci_devs_to_hide[pos]);
 	}
 
 	/* If we're the first PCI Device Driver to register, we're the
diff --git a/drivers/xen/xenbus/xenbus_xs.c b/drivers/xen/xenbus/xenbus_xs.c
index acedeab..88e677b 100644
--- a/drivers/xen/xenbus/xenbus_xs.c
+++ b/drivers/xen/xenbus/xenbus_xs.c
@@ -48,7 +48,6 @@
 #include <xen/xenbus.h>
 #include <xen/xen.h>
 #include "xenbus_comms.h"
-#include <asm/xen/hypervisor.h>
 
 struct xs_stored_msg {
 	struct list_head list;