Merge branch 'master' into for-next

Merge with latest Linus' tree, as I have incoming patches
that fix code that is newer than current HEAD of for-next.

Conflicts:
	drivers/net/ethernet/realtek/r8169.c

20 files changed, 690 insertions, 52 deletions

diff --git a/drivers/xen/Kconfig b/drivers/xen/Kconfig
index a1ced521cf74..94243136f6bf 100644
--- a/drivers/xen/Kconfig
+++ b/drivers/xen/Kconfig
@@ -178,4 +178,20 @@ config XEN_PRIVCMD
 	depends on XEN
 	default m
 
+config XEN_ACPI_PROCESSOR
+	tristate "Xen ACPI processor"
+	depends on XEN && X86 && ACPI_PROCESSOR && CPU_FREQ
+	default m
+	help
+          This ACPI processor uploads Power Management information to the Xen hypervisor.
+
+	  To do that the driver parses the Power Management data and uploads said
+	  information to the Xen hypervisor. Then the Xen hypervisor can select the
+          proper Cx and Pxx states. It also registers itslef as the SMM so that
+          other drivers (such as ACPI cpufreq scaling driver) will not load.
+
+          To compile this driver as a module, choose M here: the
+          module will be called xen_acpi_processor  If you do not know what to choose,
+          select M here. If the CPUFREQ drivers are built in, select Y here.
+
 endmenu
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile
index aa31337192cc..9adc5be57b13 100644
--- a/drivers/xen/Makefile
+++ b/drivers/xen/Makefile
@@ -20,7 +20,7 @@ obj-$(CONFIG_SWIOTLB_XEN)		+= swiotlb-xen.o
 obj-$(CONFIG_XEN_DOM0)			+= pci.o
 obj-$(CONFIG_XEN_PCIDEV_BACKEND)	+= xen-pciback/
 obj-$(CONFIG_XEN_PRIVCMD)		+= xen-privcmd.o
-
+obj-$(CONFIG_XEN_ACPI_PROCESSOR)	+= xen-acpi-processor.o
 xen-evtchn-y				:= evtchn.o
 xen-gntdev-y				:= gntdev.o
 xen-gntalloc-y				:= gntalloc.o
diff --git a/drivers/xen/cpu_hotplug.c b/drivers/xen/cpu_hotplug.c
index 14e2d995e958..4dcfced107f5 100644
--- a/drivers/xen/cpu_hotplug.c
+++ b/drivers/xen/cpu_hotplug.c
@@ -30,7 +30,8 @@ static int vcpu_online(unsigned int cpu)
 	sprintf(dir, "cpu/%u", cpu);
 	err = xenbus_scanf(XBT_NIL, dir, "availability", "%s", state);
 	if (err != 1) {
-		printk(KERN_ERR "XENBUS: Unable to read cpu state\n");
+		if (!xen_initial_domain())
+			printk(KERN_ERR "XENBUS: Unable to read cpu state\n");
 		return err;
 	}
 
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index e5e5812a1014..4b33acd8ed4e 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -37,6 +37,7 @@
 #include <asm/idle.h>
 #include <asm/io_apic.h>
 #include <asm/sync_bitops.h>
+#include <asm/xen/page.h>
 #include <asm/xen/pci.h>
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
@@ -109,6 +110,8 @@ struct irq_info {
 #define PIRQ_SHAREABLE	(1 << 1)
 
 static int *evtchn_to_irq;
+static unsigned long *pirq_eoi_map;
+static bool (*pirq_needs_eoi)(unsigned irq);
 
 static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
 		      cpu_evtchn_mask);
@@ -269,10 +272,14 @@ static unsigned int cpu_from_evtchn(unsigned int evtchn)
 	return ret;
 }
 
-static bool pirq_needs_eoi(unsigned irq)
+static bool pirq_check_eoi_map(unsigned irq)
 {
-	struct irq_info *info = info_for_irq(irq);
+	return test_bit(irq, pirq_eoi_map);
+}
 
+static bool pirq_needs_eoi_flag(unsigned irq)
+{
+	struct irq_info *info = info_for_irq(irq);
 	BUG_ON(info->type != IRQT_PIRQ);
 
 	return info->u.pirq.flags & PIRQ_NEEDS_EOI;
@@ -1768,7 +1775,7 @@ void xen_callback_vector(void) {}
 
 void __init xen_init_IRQ(void)
 {
-	int i;
+	int i, rc;
 
 	evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
 				    GFP_KERNEL);
@@ -1782,6 +1789,8 @@ void __init xen_init_IRQ(void)
 	for (i = 0; i < NR_EVENT_CHANNELS; i++)
 		mask_evtchn(i);
 
+	pirq_needs_eoi = pirq_needs_eoi_flag;
+
 	if (xen_hvm_domain()) {
 		xen_callback_vector();
 		native_init_IRQ();
@@ -1789,8 +1798,19 @@ void __init xen_init_IRQ(void)
 		 * __acpi_register_gsi can point at the right function */
 		pci_xen_hvm_init();
 	} else {
+		struct physdev_pirq_eoi_gmfn eoi_gmfn;
+
 		irq_ctx_init(smp_processor_id());
 		if (xen_initial_domain())
 			pci_xen_initial_domain();
+
+		pirq_eoi_map = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
+		eoi_gmfn.gmfn = virt_to_mfn(pirq_eoi_map);
+		rc = HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn_v2, &eoi_gmfn);
+		if (rc != 0) {
+			free_page((unsigned long) pirq_eoi_map);
+			pirq_eoi_map = NULL;
+		} else
+			pirq_needs_eoi = pirq_check_eoi_map;
 	}
 }
diff --git a/drivers/xen/manage.c b/drivers/xen/manage.c
index ce4fa0831860..9e14ae6cd49c 100644
--- a/drivers/xen/manage.c
+++ b/drivers/xen/manage.c
@@ -129,9 +129,9 @@ static void do_suspend(void)
 	printk(KERN_DEBUG "suspending xenstore...\n");
 	xs_suspend();
 
-	err = dpm_suspend_noirq(PMSG_FREEZE);
+	err = dpm_suspend_end(PMSG_FREEZE);
 	if (err) {
-		printk(KERN_ERR "dpm_suspend_noirq failed: %d\n", err);
+		printk(KERN_ERR "dpm_suspend_end failed: %d\n", err);
 		goto out_resume;
 	}
 
@@ -149,7 +149,7 @@ static void do_suspend(void)
 
 	err = stop_machine(xen_suspend, &si, cpumask_of(0));
 
-	dpm_resume_noirq(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
+	dpm_resume_start(si.cancelled ? PMSG_THAW : PMSG_RESTORE);
 
 	if (err) {
 		printk(KERN_ERR "failed to start xen_suspend: %d\n", err);
diff --git a/drivers/xen/platform-pci.c b/drivers/xen/platform-pci.c
index 319dd0a94d51..2389e581e23c 100644
--- a/drivers/xen/platform-pci.c
+++ b/drivers/xen/platform-pci.c
@@ -186,11 +186,6 @@ static struct pci_driver platform_driver = {
 
 static int __init platform_pci_module_init(void)
 {
-	/* no unplug has been done, IGNORE hasn't been specified: just
-	 * return now */
-	if (!xen_platform_pci_unplug)
-		return -ENODEV;
-
 	return pci_register_driver(&platform_driver);
 }
 
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 19e6a2041371..1afb4fba11b4 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -204,7 +204,8 @@ error:
 
 void *
 xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
-			   dma_addr_t *dma_handle, gfp_t flags)
+			   dma_addr_t *dma_handle, gfp_t flags,
+			   struct dma_attrs *attrs)
 {
 	void *ret;
 	int order = get_order(size);
@@ -253,7 +254,7 @@ EXPORT_SYMBOL_GPL(xen_swiotlb_alloc_coherent);
 
 void
 xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
-			  dma_addr_t dev_addr)
+			  dma_addr_t dev_addr, struct dma_attrs *attrs)
 {
 	int order = get_order(size);
 	phys_addr_t phys;
diff --git a/drivers/xen/sys-hypervisor.c b/drivers/xen/sys-hypervisor.c
index 1e0fe01eb670..fdb6d229c9bb 100644
--- a/drivers/xen/sys-hypervisor.c
+++ b/drivers/xen/sys-hypervisor.c
@@ -97,7 +97,7 @@ static struct attribute *version_attrs[] = {
 	NULL
 };
 
-static struct attribute_group version_group = {
+static const struct attribute_group version_group = {
 	.name = "version",
 	.attrs = version_attrs,
 };
@@ -210,7 +210,7 @@ static struct attribute *xen_compile_attrs[] = {
 	NULL
 };
 
-static struct attribute_group xen_compilation_group = {
+static const struct attribute_group xen_compilation_group = {
 	.name = "compilation",
 	.attrs = xen_compile_attrs,
 };
@@ -340,7 +340,7 @@ static struct attribute *xen_properties_attrs[] = {
 	NULL
 };
 
-static struct attribute_group xen_properties_group = {
+static const struct attribute_group xen_properties_group = {
 	.name = "properties",
 	.attrs = xen_properties_attrs,
 };
diff --git a/drivers/xen/tmem.c b/drivers/xen/tmem.c
index d369965e8f8a..dcb79521e6c8 100644
--- a/drivers/xen/tmem.c
+++ b/drivers/xen/tmem.c
@@ -9,7 +9,6 @@
 #include <linux/types.h>
 #include <linux/init.h>
 #include <linux/pagemap.h>
-#include <linux/module.h>
 #include <linux/cleancache.h>
 
 /* temporary ifdef until include/linux/frontswap.h is upstream */
@@ -128,15 +127,13 @@ static int xen_tmem_flush_object(u32 pool_id, struct tmem_oid oid)
 	return xen_tmem_op(TMEM_FLUSH_OBJECT, pool_id, oid, 0, 0, 0, 0, 0);
 }
 
-int tmem_enabled __read_mostly;
-EXPORT_SYMBOL(tmem_enabled);
+bool __read_mostly tmem_enabled = false;
 
 static int __init enable_tmem(char *s)
 {
-	tmem_enabled = 1;
+	tmem_enabled = true;
 	return 1;
 }
-
 __setup("tmem", enable_tmem);
 
 #ifdef CONFIG_CLEANCACHE
@@ -229,22 +226,21 @@ static int tmem_cleancache_init_shared_fs(char *uuid, size_t pagesize)
 	return xen_tmem_new_pool(shared_uuid, TMEM_POOL_SHARED, pagesize);
 }
 
-static int use_cleancache = 1;
+static bool __initdata use_cleancache = true;
 
 static int __init no_cleancache(char *s)
 {
-	use_cleancache = 0;
+	use_cleancache = false;
 	return 1;
 }
-
 __setup("nocleancache", no_cleancache);
 
-static struct cleancache_ops tmem_cleancache_ops = {
+static struct cleancache_ops __initdata tmem_cleancache_ops = {
 	.put_page = tmem_cleancache_put_page,
 	.get_page = tmem_cleancache_get_page,
-	.flush_page = tmem_cleancache_flush_page,
-	.flush_inode = tmem_cleancache_flush_inode,
-	.flush_fs = tmem_cleancache_flush_fs,
+	.invalidate_page = tmem_cleancache_flush_page,
+	.invalidate_inode = tmem_cleancache_flush_inode,
+	.invalidate_fs = tmem_cleancache_flush_fs,
 	.init_shared_fs = tmem_cleancache_init_shared_fs,
 	.init_fs = tmem_cleancache_init_fs
 };
@@ -356,21 +352,20 @@ static void tmem_frontswap_init(unsigned ignored)
 		    xen_tmem_new_pool(private, TMEM_POOL_PERSIST, PAGE_SIZE);
 }
 
-static int __initdata use_frontswap = 1;
+static bool __initdata use_frontswap = true;
 
 static int __init no_frontswap(char *s)
 {
-	use_frontswap = 0;
+	use_frontswap = false;
 	return 1;
 }
-
 __setup("nofrontswap", no_frontswap);
 
-static struct frontswap_ops tmem_frontswap_ops = {
+static struct frontswap_ops __initdata tmem_frontswap_ops = {
 	.put_page = tmem_frontswap_put_page,
 	.get_page = tmem_frontswap_get_page,
-	.flush_page = tmem_frontswap_flush_page,
-	.flush_area = tmem_frontswap_flush_area,
+	.invalidate_page = tmem_frontswap_flush_page,
+	.invalidate_area = tmem_frontswap_flush_area,
 	.init = tmem_frontswap_init
 };
 #endif
diff --git a/drivers/xen/xen-acpi-processor.c b/drivers/xen/xen-acpi-processor.c
new file mode 100644
index 000000000000..174b5653cd8a
--- /dev/null
+++ b/drivers/xen/xen-acpi-processor.c
@@ -0,0 +1,562 @@
+/*
+ * Copyright 2012 by Oracle Inc
+ * Author: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
+ *
+ * This code borrows ideas from https://lkml.org/lkml/2011/11/30/249
+ * so many thanks go to Kevin Tian <kevin.tian@intel.com>
+ * and Yu Ke <ke.yu@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/cpumask.h>
+#include <linux/cpufreq.h>
+#include <linux/freezer.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <acpi/acpi_bus.h>
+#include <acpi/acpi_drivers.h>
+#include <acpi/processor.h>
+
+#include <xen/interface/platform.h>
+#include <asm/xen/hypercall.h>
+
+#define DRV_NAME "xen-acpi-processor: "
+
+static int no_hypercall;
+MODULE_PARM_DESC(off, "Inhibit the hypercall.");
+module_param_named(off, no_hypercall, int, 0400);
+
+/*
+ * Note: Do not convert the acpi_id* below to cpumask_var_t or use cpumask_bit
+ * - as those shrink to nr_cpu_bits (which is dependent on possible_cpu), which
+ * can be less than what we want to put in. Instead use the 'nr_acpi_bits'
+ * which is dynamically computed based on the MADT or x2APIC table.
+ */
+static unsigned int nr_acpi_bits;
+/* Mutex to protect the acpi_ids_done - for CPU hotplug use. */
+static DEFINE_MUTEX(acpi_ids_mutex);
+/* Which ACPI ID we have processed from 'struct acpi_processor'. */
+static unsigned long *acpi_ids_done;
+/* Which ACPI ID exist in the SSDT/DSDT processor definitions. */
+static unsigned long __initdata *acpi_id_present;
+/* And if there is an _CST definition (or a PBLK) for the ACPI IDs */
+static unsigned long __initdata *acpi_id_cst_present;
+
+static int push_cxx_to_hypervisor(struct acpi_processor *_pr)
+{
+	struct xen_platform_op op = {
+		.cmd			= XENPF_set_processor_pminfo,
+		.interface_version	= XENPF_INTERFACE_VERSION,
+		.u.set_pminfo.id	= _pr->acpi_id,
+		.u.set_pminfo.type	= XEN_PM_CX,
+	};
+	struct xen_processor_cx *dst_cx, *dst_cx_states = NULL;
+	struct acpi_processor_cx *cx;
+	unsigned int i, ok;
+	int ret = 0;
+
+	dst_cx_states = kcalloc(_pr->power.count,
+				sizeof(struct xen_processor_cx), GFP_KERNEL);
+	if (!dst_cx_states)
+		return -ENOMEM;
+
+	for (ok = 0, i = 1; i <= _pr->power.count; i++) {
+		cx = &_pr->power.states[i];
+		if (!cx->valid)
+			continue;
+
+		dst_cx = &(dst_cx_states[ok++]);
+
+		dst_cx->reg.space_id = ACPI_ADR_SPACE_SYSTEM_IO;
+		if (cx->entry_method == ACPI_CSTATE_SYSTEMIO) {
+			dst_cx->reg.bit_width = 8;
+			dst_cx->reg.bit_offset = 0;
+			dst_cx->reg.access_size = 1;
+		} else {
+			dst_cx->reg.space_id = ACPI_ADR_SPACE_FIXED_HARDWARE;
+			if (cx->entry_method == ACPI_CSTATE_FFH) {
+				/* NATIVE_CSTATE_BEYOND_HALT */
+				dst_cx->reg.bit_offset = 2;
+				dst_cx->reg.bit_width = 1; /* VENDOR_INTEL */
+			}
+			dst_cx->reg.access_size = 0;
+		}
+		dst_cx->reg.address = cx->address;
+
+		dst_cx->type = cx->type;
+		dst_cx->latency = cx->latency;
+		dst_cx->power = cx->power;
+
+		dst_cx->dpcnt = 0;
+		set_xen_guest_handle(dst_cx->dp, NULL);
+	}
+	if (!ok) {
+		pr_debug(DRV_NAME "No _Cx for ACPI CPU %u\n", _pr->acpi_id);
+		kfree(dst_cx_states);
+		return -EINVAL;
+	}
+	op.u.set_pminfo.power.count = ok;
+	op.u.set_pminfo.power.flags.bm_control = _pr->flags.bm_control;
+	op.u.set_pminfo.power.flags.bm_check = _pr->flags.bm_check;
+	op.u.set_pminfo.power.flags.has_cst = _pr->flags.has_cst;
+	op.u.set_pminfo.power.flags.power_setup_done =
+		_pr->flags.power_setup_done;
+
+	set_xen_guest_handle(op.u.set_pminfo.power.states, dst_cx_states);
+
+	if (!no_hypercall)
+		ret = HYPERVISOR_dom0_op(&op);
+
+	if (!ret) {
+		pr_debug("ACPI CPU%u - C-states uploaded.\n", _pr->acpi_id);
+		for (i = 1; i <= _pr->power.count; i++) {
+			cx = &_pr->power.states[i];
+			if (!cx->valid)
+				continue;
+			pr_debug("     C%d: %s %d uS\n",
+				 cx->type, cx->desc, (u32)cx->latency);
+		}
+	} else
+		pr_err(DRV_NAME "(CX): Hypervisor error (%d) for ACPI CPU%u\n",
+		       ret, _pr->acpi_id);
+
+	kfree(dst_cx_states);
+
+	return ret;
+}
+static struct xen_processor_px *
+xen_copy_pss_data(struct acpi_processor *_pr,
+		  struct xen_processor_performance *dst_perf)
+{
+	struct xen_processor_px *dst_states = NULL;
+	unsigned int i;
+
+	BUILD_BUG_ON(sizeof(struct xen_processor_px) !=
+		     sizeof(struct acpi_processor_px));
+
+	dst_states = kcalloc(_pr->performance->state_count,
+			     sizeof(struct xen_processor_px), GFP_KERNEL);
+	if (!dst_states)
+		return ERR_PTR(-ENOMEM);
+
+	dst_perf->state_count = _pr->performance->state_count;
+	for (i = 0; i < _pr->performance->state_count; i++) {
+		/* Fortunatly for us, they are both the same size */
+		memcpy(&(dst_states[i]), &(_pr->performance->states[i]),
+		       sizeof(struct acpi_processor_px));
+	}
+	return dst_states;
+}
+static int xen_copy_psd_data(struct acpi_processor *_pr,
+			     struct xen_processor_performance *dst)
+{
+	struct acpi_psd_package *pdomain;
+
+	BUILD_BUG_ON(sizeof(struct xen_psd_package) !=
+		     sizeof(struct acpi_psd_package));
+
+	/* This information is enumerated only if acpi_processor_preregister_performance
+	 * has been called.
+	 */
+	dst->shared_type = _pr->performance->shared_type;
+
+	pdomain = &(_pr->performance->domain_info);
+
+	/* 'acpi_processor_preregister_performance' does not parse if the
+	 * num_processors <= 1, but Xen still requires it. Do it manually here.
+	 */
+	if (pdomain->num_processors <= 1) {
+		if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL)
+			dst->shared_type = CPUFREQ_SHARED_TYPE_ALL;
+		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL)
+			dst->shared_type = CPUFREQ_SHARED_TYPE_HW;
+		else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY)
+			dst->shared_type = CPUFREQ_SHARED_TYPE_ANY;
+
+	}
+	memcpy(&(dst->domain_info), pdomain, sizeof(struct acpi_psd_package));
+	return 0;
+}
+static int xen_copy_pct_data(struct acpi_pct_register *pct,
+			     struct xen_pct_register *dst_pct)
+{
+	/* It would be nice if you could just do 'memcpy(pct, dst_pct') but
+	 * sadly the Xen structure did not have the proper padding so the
+	 * descriptor field takes two (dst_pct) bytes instead of one (pct).
+	 */
+	dst_pct->descriptor = pct->descriptor;
+	dst_pct->length = pct->length;
+	dst_pct->space_id = pct->space_id;
+	dst_pct->bit_width = pct->bit_width;
+	dst_pct->bit_offset = pct->bit_offset;
+	dst_pct->reserved = pct->reserved;
+	dst_pct->address = pct->address;
+	return 0;
+}
+static int push_pxx_to_hypervisor(struct acpi_processor *_pr)
+{
+	int ret = 0;
+	struct xen_platform_op op = {
+		.cmd			= XENPF_set_processor_pminfo,
+		.interface_version	= XENPF_INTERFACE_VERSION,
+		.u.set_pminfo.id	= _pr->acpi_id,
+		.u.set_pminfo.type	= XEN_PM_PX,
+	};
+	struct xen_processor_performance *dst_perf;
+	struct xen_processor_px *dst_states = NULL;
+
+	dst_perf = &op.u.set_pminfo.perf;
+
+	dst_perf->platform_limit = _pr->performance_platform_limit;
+	dst_perf->flags |= XEN_PX_PPC;
+	xen_copy_pct_data(&(_pr->performance->control_register),
+			  &dst_perf->control_register);
+	xen_copy_pct_data(&(_pr->performance->status_register),
+			  &dst_perf->status_register);
+	dst_perf->flags |= XEN_PX_PCT;
+	dst_states = xen_copy_pss_data(_pr, dst_perf);
+	if (!IS_ERR_OR_NULL(dst_states)) {
+		set_xen_guest_handle(dst_perf->states, dst_states);
+		dst_perf->flags |= XEN_PX_PSS;
+	}
+	if (!xen_copy_psd_data(_pr, dst_perf))
+		dst_perf->flags |= XEN_PX_PSD;
+
+	if (dst_perf->flags != (XEN_PX_PSD | XEN_PX_PSS | XEN_PX_PCT | XEN_PX_PPC)) {
+		pr_warn(DRV_NAME "ACPI CPU%u missing some P-state data (%x), skipping.\n",
+			_pr->acpi_id, dst_perf->flags);
+		ret = -ENODEV;
+		goto err_free;
+	}
+
+	if (!no_hypercall)
+		ret = HYPERVISOR_dom0_op(&op);
+
+	if (!ret) {
+		struct acpi_processor_performance *perf;
+		unsigned int i;
+
+		perf = _pr->performance;
+		pr_debug("ACPI CPU%u - P-states uploaded.\n", _pr->acpi_id);
+		for (i = 0; i < perf->state_count; i++) {
+			pr_debug("     %cP%d: %d MHz, %d mW, %d uS\n",
+			(i == perf->state ? '*' : ' '), i,
+			(u32) perf->states[i].core_frequency,
+			(u32) perf->states[i].power,
+			(u32) perf->states[i].transition_latency);
+		}
+	} else if (ret != -EINVAL)
+		/* EINVAL means the ACPI ID is incorrect - meaning the ACPI
+		 * table is referencing a non-existing CPU - which can happen
+		 * with broken ACPI tables. */
+		pr_warn(DRV_NAME "(_PXX): Hypervisor error (%d) for ACPI CPU%u\n",
+		       ret, _pr->acpi_id);
+err_free:
+	if (!IS_ERR_OR_NULL(dst_states))
+		kfree(dst_states);
+
+	return ret;
+}
+static int upload_pm_data(struct acpi_processor *_pr)
+{
+	int err = 0;
+
+	mutex_lock(&acpi_ids_mutex);
+	if (__test_and_set_bit(_pr->acpi_id, acpi_ids_done)) {
+		mutex_unlock(&acpi_ids_mutex);
+		return -EBUSY;
+	}
+	if (_pr->flags.power)
+		err = push_cxx_to_hypervisor(_pr);
+
+	if (_pr->performance && _pr->performance->states)
+		err |= push_pxx_to_hypervisor(_pr);
+
+	mutex_unlock(&acpi_ids_mutex);
+	return err;
+}
+static unsigned int __init get_max_acpi_id(void)
+{
+	struct xenpf_pcpuinfo *info;
+	struct xen_platform_op op = {
+		.cmd = XENPF_get_cpuinfo,
+		.interface_version = XENPF_INTERFACE_VERSION,
+	};
+	int ret = 0;
+	unsigned int i, last_cpu, max_acpi_id = 0;
+
+	info = &op.u.pcpu_info;
+	info->xen_cpuid = 0;
+
+	ret = HYPERVISOR_dom0_op(&op);
+	if (ret)
+		return NR_CPUS;
+
+	/* The max_present is the same irregardless of the xen_cpuid */
+	last_cpu = op.u.pcpu_info.max_present;
+	for (i = 0; i <= last_cpu; i++) {
+		info->xen_cpuid = i;
+		ret = HYPERVISOR_dom0_op(&op);
+		if (ret)
+			continue;
+		max_acpi_id = max(info->acpi_id, max_acpi_id);
+	}
+	max_acpi_id *= 2; /* Slack for CPU hotplug support. */
+	pr_debug(DRV_NAME "Max ACPI ID: %u\n", max_acpi_id);
+	return max_acpi_id;
+}
+/*
+ * The read_acpi_id and check_acpi_ids are there to support the Xen
+ * oddity of virtual CPUs != physical CPUs in the initial domain.
+ * The user can supply 'xen_max_vcpus=X' on the Xen hypervisor line
+ * which will band the amount of CPUs the initial domain can see.
+ * In general that is OK, except it plays havoc with any of the
+ * for_each_[present|online]_cpu macros which are banded to the virtual
+ * CPU amount.
+ */
+static acpi_status __init
+read_acpi_id(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+	u32 acpi_id;
+	acpi_status status;
+	acpi_object_type acpi_type;
+	unsigned long long tmp;
+	union acpi_object object = { 0 };
+	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
+	acpi_io_address pblk = 0;
+
+	status = acpi_get_type(handle, &acpi_type);
+	if (ACPI_FAILURE(status))
+		return AE_OK;
+
+	switch (acpi_type) {
+	case ACPI_TYPE_PROCESSOR:
+		status = acpi_evaluate_object(handle, NULL, NULL, &buffer);
+		if (ACPI_FAILURE(status))
+			return AE_OK;
+		acpi_id = object.processor.proc_id;
+		pblk = object.processor.pblk_address;
+		break;
+	case ACPI_TYPE_DEVICE:
+		status = acpi_evaluate_integer(handle, "_UID", NULL, &tmp);
+		if (ACPI_FAILURE(status))
+			return AE_OK;
+		acpi_id = tmp;
+		break;
+	default:
+		return AE_OK;
+	}
+	/* There are more ACPI Processor objects than in x2APIC or MADT.
+	 * This can happen with incorrect ACPI SSDT declerations. */
+	if (acpi_id > nr_acpi_bits) {
+		pr_debug(DRV_NAME "We only have %u, trying to set %u\n",
+			 nr_acpi_bits, acpi_id);
+		return AE_OK;
+	}
+	/* OK, There is a ACPI Processor object */
+	__set_bit(acpi_id, acpi_id_present);
+
+	pr_debug(DRV_NAME "ACPI CPU%u w/ PBLK:0x%lx\n", acpi_id,
+		 (unsigned long)pblk);
+
+	status = acpi_evaluate_object(handle, "_CST", NULL, &buffer);
+	if (ACPI_FAILURE(status)) {
+		if (!pblk)
+			return AE_OK;
+	}
+	/* .. and it has a C-state */
+	__set_bit(acpi_id, acpi_id_cst_present);
+
+	return AE_OK;
+}
+static int __init check_acpi_ids(struct acpi_processor *pr_backup)
+{
+
+	if (!pr_backup)
+		return -ENODEV;
+
+	/* All online CPUs have been processed at this stage. Now verify
+	 * whether in fact "online CPUs" == physical CPUs.
+	 */
+	acpi_id_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
+	if (!acpi_id_present)
+		return -ENOMEM;
+
+	acpi_id_cst_present = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
+	if (!acpi_id_cst_present) {
+		kfree(acpi_id_present);
+		return -ENOMEM;
+	}
+
+	acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
+			    ACPI_UINT32_MAX,
+			    read_acpi_id, NULL, NULL, NULL);
+	acpi_get_devices("ACPI0007", read_acpi_id, NULL, NULL);
+
+	if (!bitmap_equal(acpi_id_present, acpi_ids_done, nr_acpi_bits)) {
+		unsigned int i;
+		for_each_set_bit(i, acpi_id_present, nr_acpi_bits) {
+			pr_backup->acpi_id = i;
+			/* Mask out C-states if there are no _CST or PBLK */
+			pr_backup->flags.power = test_bit(i, acpi_id_cst_present);
+			(void)upload_pm_data(pr_backup);
+		}
+	}
+	kfree(acpi_id_present);
+	acpi_id_present = NULL;
+	kfree(acpi_id_cst_present);
+	acpi_id_cst_present = NULL;
+	return 0;
+}
+static int __init check_prereq(void)
+{
+	struct cpuinfo_x86 *c = &cpu_data(0);
+
+	if (!xen_initial_domain())
+		return -ENODEV;
+
+	if (!acpi_gbl_FADT.smi_command)
+		return -ENODEV;
+
+	if (c->x86_vendor == X86_VENDOR_INTEL) {
+		if (!cpu_has(c, X86_FEATURE_EST))
+			return -ENODEV;
+
+		return 0;
+	}
+	if (c->x86_vendor == X86_VENDOR_AMD) {
+		/* Copied from powernow-k8.h, can't include ../cpufreq/powernow
+		 * as we get compile warnings for the static functions.
+		 */
+#define CPUID_FREQ_VOLT_CAPABILITIES    0x80000007
+#define USE_HW_PSTATE                   0x00000080
+		u32 eax, ebx, ecx, edx;
+		cpuid(CPUID_FREQ_VOLT_CAPABILITIES, &eax, &ebx, &ecx, &edx);
+		if ((edx & USE_HW_PSTATE) != USE_HW_PSTATE)
+			return -ENODEV;
+		return 0;
+	}
+	return -ENODEV;
+}
+/* acpi_perf_data is a pointer to percpu data. */
+static struct acpi_processor_performance __percpu *acpi_perf_data;
+
+static void free_acpi_perf_data(void)
+{
+	unsigned int i;
+
+	/* Freeing a NULL pointer is OK, and alloc_percpu zeroes. */
+	for_each_possible_cpu(i)
+		free_cpumask_var(per_cpu_ptr(acpi_perf_data, i)
+				 ->shared_cpu_map);
+	free_percpu(acpi_perf_data);
+}
+
+static int __init xen_acpi_processor_init(void)
+{
+	struct acpi_processor *pr_backup = NULL;
+	unsigned int i;
+	int rc = check_prereq();
+
+	if (rc)
+		return rc;
+
+	nr_acpi_bits = get_max_acpi_id() + 1;
+	acpi_ids_done = kcalloc(BITS_TO_LONGS(nr_acpi_bits), sizeof(unsigned long), GFP_KERNEL);
+	if (!acpi_ids_done)
+		return -ENOMEM;
+
+	acpi_perf_data = alloc_percpu(struct acpi_processor_performance);
+	if (!acpi_perf_data) {
+		pr_debug(DRV_NAME "Memory allocation error for acpi_perf_data.\n");
+		kfree(acpi_ids_done);
+		return -ENOMEM;
+	}
+	for_each_possible_cpu(i) {
+		if (!zalloc_cpumask_var_node(
+			&per_cpu_ptr(acpi_perf_data, i)->shared_cpu_map,
+			GFP_KERNEL, cpu_to_node(i))) {
+			rc = -ENOMEM;
+			goto err_out;
+		}
+	}
+
+	/* Do initialization in ACPI core. It is OK to fail here. */
+	(void)acpi_processor_preregister_performance(acpi_perf_data);
+
+	for_each_possible_cpu(i) {
+		struct acpi_processor_performance *perf;
+
+		perf = per_cpu_ptr(acpi_perf_data, i);
+		rc = acpi_processor_register_performance(perf, i);
+		if (rc)
+			goto err_out;
+	}
+	rc = acpi_processor_notify_smm(THIS_MODULE);
+	if (rc)
+		goto err_unregister;
+
+	for_each_possible_cpu(i) {
+		struct acpi_processor *_pr;
+		_pr = per_cpu(processors, i /* APIC ID */);
+		if (!_pr)
+			continue;
+
+		if (!pr_backup) {
+			pr_backup = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
+			memcpy(pr_backup, _pr, sizeof(struct acpi_processor));
+		}
+		(void)upload_pm_data(_pr);
+	}
+	rc = check_acpi_ids(pr_backup);
+	if (rc)
+		goto err_unregister;
+
+	kfree(pr_backup);
+
+	return 0;
+err_unregister:
+	for_each_possible_cpu(i) {
+		struct acpi_processor_performance *perf;
+		perf = per_cpu_ptr(acpi_perf_data, i);
+		acpi_processor_unregister_performance(perf, i);
+	}
+err_out:
+	/* Freeing a NULL pointer is OK: alloc_percpu zeroes. */
+	free_acpi_perf_data();
+	kfree(acpi_ids_done);
+	return rc;
+}
+static void __exit xen_acpi_processor_exit(void)
+{
+	int i;
+
+	kfree(acpi_ids_done);
+	for_each_possible_cpu(i) {
+		struct acpi_processor_performance *perf;
+		perf = per_cpu_ptr(acpi_perf_data, i);
+		acpi_processor_unregister_performance(perf, i);
+	}
+	free_acpi_perf_data();
+}
+
+MODULE_AUTHOR("Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>");
+MODULE_DESCRIPTION("Xen ACPI Processor P-states (and Cx) driver which uploads PM data to Xen hypervisor");
+MODULE_LICENSE("GPL");
+
+/* We want to be loaded before the CPU freq scaling drivers are loaded.
+ * They are loaded in late_initcall. */
+device_initcall(xen_acpi_processor_init);
+module_exit(xen_acpi_processor_exit);
diff --git a/drivers/xen/xen-balloon.c b/drivers/xen/xen-balloon.c
index 596e6a7b17d6..8f37e23f6d13 100644
--- a/drivers/xen/xen-balloon.c
+++ b/drivers/xen/xen-balloon.c
@@ -207,7 +207,7 @@ static struct attribute *balloon_info_attrs[] = {
 	NULL
 };
 
-static struct attribute_group balloon_info_group = {
+static const struct attribute_group balloon_info_group = {
 	.name = "info",
 	.attrs = balloon_info_attrs
 };
diff --git a/drivers/xen/xen-pciback/pci_stub.c b/drivers/xen/xen-pciback/pci_stub.c
index 7944a17f5cbf..097e536e8672 100644
--- a/drivers/xen/xen-pciback/pci_stub.c
+++ b/drivers/xen/xen-pciback/pci_stub.c
@@ -85,19 +85,34 @@ static struct pcistub_device *pcistub_device_alloc(struct pci_dev *dev)
 static void pcistub_device_release(struct kref *kref)
 {
 	struct pcistub_device *psdev;
+	struct xen_pcibk_dev_data *dev_data;
 
 	psdev = container_of(kref, struct pcistub_device, kref);
+	dev_data = pci_get_drvdata(psdev->dev);
 
 	dev_dbg(&psdev->dev->dev, "pcistub_device_release\n");
 
 	xen_unregister_device_domain_owner(psdev->dev);
 
-	/* Clean-up the device */
+	/* Call the reset function which does not take lock as this
+	 * is called from "unbind" which takes a device_lock mutex.
+	 */
+	__pci_reset_function_locked(psdev->dev);
+	if (pci_load_and_free_saved_state(psdev->dev,
+					  &dev_data->pci_saved_state)) {
+		dev_dbg(&psdev->dev->dev, "Could not reload PCI state\n");
+	} else
+		pci_restore_state(psdev->dev);
+
+	/* Disable the device */
 	xen_pcibk_reset_device(psdev->dev);
+
+	kfree(dev_data);
+	pci_set_drvdata(psdev->dev, NULL);
+
+	/* Clean-up the device */
 	xen_pcibk_config_free_dyn_fields(psdev->dev);
 	xen_pcibk_config_free_dev(psdev->dev);
-	kfree(pci_get_drvdata(psdev->dev));
-	pci_set_drvdata(psdev->dev, NULL);
 
 	psdev->dev->dev_flags &= ~PCI_DEV_FLAGS_ASSIGNED;
 	pci_dev_put(psdev->dev);
@@ -231,7 +246,17 @@ void pcistub_put_pci_dev(struct pci_dev *dev)
 	/* Cleanup our device
 	 * (so it's ready for the next domain)
 	 */
+
+	/* This is OK - we are running from workqueue context
+	 * and want to inhibit the user from fiddling with 'reset'
+	 */
+	pci_reset_function(dev);
+	pci_restore_state(psdev->dev);
+
+	/* This disables the device. */
 	xen_pcibk_reset_device(found_psdev->dev);
+
+	/* And cleanup up our emulated fields. */
 	xen_pcibk_config_free_dyn_fields(found_psdev->dev);
 	xen_pcibk_config_reset_dev(found_psdev->dev);
 
@@ -328,6 +353,16 @@ static int __devinit pcistub_init_device(struct pci_dev *dev)
 	if (err)
 		goto config_release;
 
+	dev_dbg(&dev->dev, "reseting (FLR, D3, etc) the device\n");
+	__pci_reset_function_locked(dev);
+
+	/* We need the device active to save the state. */
+	dev_dbg(&dev->dev, "save state of device\n");
+	pci_save_state(dev);
+	dev_data->pci_saved_state = pci_store_saved_state(dev);
+	if (!dev_data->pci_saved_state)
+		dev_err(&dev->dev, "Could not store PCI conf saved state!\n");
+
 	/* Now disable the device (this also ensures some private device
 	 * data is setup before we export)
 	 */
@@ -884,7 +919,7 @@ static inline int str_to_quirk(const char *buf, int *domain, int *bus, int
 	int err;
 
 	err =
-	    sscanf(buf, " %04x:%02x:%02x.%1x-%08x:%1x:%08x", domain, bus, slot,
+	    sscanf(buf, " %04x:%02x:%02x.%d-%08x:%1x:%08x", domain, bus, slot,
 		   func, reg, size, mask);
 	if (err == 7)
 		return 0;
@@ -904,7 +939,7 @@ static int pcistub_device_id_add(int domain, int bus, int slot, int func)
 	pci_dev_id->bus = bus;
 	pci_dev_id->devfn = PCI_DEVFN(slot, func);
 
-	pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%01x\n",
+	pr_debug(DRV_NAME ": wants to seize %04x:%02x:%02x.%d\n",
 		 domain, bus, slot, func);
 
 	spin_lock_irqsave(&device_ids_lock, flags);
@@ -934,7 +969,7 @@ static int pcistub_device_id_remove(int domain, int bus, int slot, int func)
 
 			err = 0;
 
-			pr_debug(DRV_NAME ": removed %04x:%02x:%02x.%01x from "
+			pr_debug(DRV_NAME ": removed %04x:%02x:%02x.%d from "
 				 "seize list\n", domain, bus, slot, func);
 		}
 	}
@@ -1029,7 +1064,7 @@ static ssize_t pcistub_slot_show(struct device_driver *drv, char *buf)
 			break;
 
 		count += scnprintf(buf + count, PAGE_SIZE - count,
-				   "%04x:%02x:%02x.%01x\n",
+				   "%04x:%02x:%02x.%d\n",
 				   pci_dev_id->domain, pci_dev_id->bus,
 				   PCI_SLOT(pci_dev_id->devfn),
 				   PCI_FUNC(pci_dev_id->devfn));
diff --git a/drivers/xen/xen-pciback/pciback.h b/drivers/xen/xen-pciback/pciback.h
index e9b4011c5f9a..a7def010eba3 100644
--- a/drivers/xen/xen-pciback/pciback.h
+++ b/drivers/xen/xen-pciback/pciback.h
@@ -41,6 +41,7 @@ struct xen_pcibk_device {
 
 struct xen_pcibk_dev_data {
 	struct list_head config_fields;
+	struct pci_saved_state *pci_saved_state;
 	unsigned int permissive:1;
 	unsigned int warned_on_write:1;
 	unsigned int enable_intx:1;
diff --git a/drivers/xen/xen-pciback/pciback_ops.c b/drivers/xen/xen-pciback/pciback_ops.c
index 63616d7453e6..97f5d264c31e 100644
--- a/drivers/xen/xen-pciback/pciback_ops.c
+++ b/drivers/xen/xen-pciback/pciback_ops.c
@@ -234,7 +234,7 @@ int xen_pcibk_enable_msix(struct xen_pcibk_device *pdev,
 	if (dev_data)
 		dev_data->ack_intr = 0;
 
-	return result;
+	return result > 0 ? 0 : result;
 }
 
 static
diff --git a/drivers/xen/xen-pciback/xenbus.c b/drivers/xen/xen-pciback/xenbus.c
index d5dcf8d5d3d9..64b11f99eacc 100644
--- a/drivers/xen/xen-pciback/xenbus.c
+++ b/drivers/xen/xen-pciback/xenbus.c
@@ -206,6 +206,7 @@ static int xen_pcibk_publish_pci_dev(struct xen_pcibk_device *pdev,
 		goto out;
 	}
 
+	/* Note: The PV protocol uses %02x, don't change it */
 	err = xenbus_printf(XBT_NIL, pdev->xdev->nodename, str,
 			    "%04x:%02x:%02x.%02x", domain, bus,
 			    PCI_SLOT(devfn), PCI_FUNC(devfn));
@@ -229,7 +230,7 @@ static int xen_pcibk_export_device(struct xen_pcibk_device *pdev,
 		err = -EINVAL;
 		xenbus_dev_fatal(pdev->xdev, err,
 				 "Couldn't locate PCI device "
-				 "(%04x:%02x:%02x.%01x)! "
+				 "(%04x:%02x:%02x.%d)! "
 				 "perhaps already in-use?",
 				 domain, bus, slot, func);
 		goto out;
@@ -274,7 +275,7 @@ static int xen_pcibk_remove_device(struct xen_pcibk_device *pdev,
 	if (!dev) {
 		err = -EINVAL;
 		dev_dbg(&pdev->xdev->dev, "Couldn't locate PCI device "
-			"(%04x:%02x:%02x.%01x)! not owned by this domain\n",
+			"(%04x:%02x:%02x.%d)! not owned by this domain\n",
 			domain, bus, slot, func);
 		goto out;
 	}
diff --git a/drivers/xen/xen-selfballoon.c b/drivers/xen/xen-selfballoon.c
index 767ff656d5a7..146c94897016 100644
--- a/drivers/xen/xen-selfballoon.c
+++ b/drivers/xen/xen-selfballoon.c
@@ -488,7 +488,7 @@ static struct attribute *selfballoon_attrs[] = {
 	NULL
 };
 
-static struct attribute_group selfballoon_group = {
+static const struct attribute_group selfballoon_group = {
 	.name = "selfballoon",
 	.attrs = selfballoon_attrs
 };
diff --git a/drivers/xen/xenbus/xenbus_client.c b/drivers/xen/xenbus/xenbus_client.c
index 566d2adbd6ea..b3e146edb51d 100644
--- a/drivers/xen/xenbus/xenbus_client.c
+++ b/drivers/xen/xenbus/xenbus_client.c
@@ -569,7 +569,7 @@ int xenbus_map_ring(struct xenbus_device *dev, int gnt_ref,
 {
 	struct gnttab_map_grant_ref op;
 
-	gnttab_set_map_op(&op, (phys_addr_t)vaddr, GNTMAP_host_map, gnt_ref,
+	gnttab_set_map_op(&op, (unsigned long)vaddr, GNTMAP_host_map, gnt_ref,
 			  dev->otherend_id);
 
 	if (HYPERVISOR_grant_table_op(GNTTABOP_map_grant_ref, &op, 1))
@@ -662,7 +662,7 @@ static int xenbus_unmap_ring_vfree_hvm(struct xenbus_device *dev, void *vaddr)
 			goto found;
 		}
 	}
-	node = NULL;
+	node = addr = NULL;
  found:
 	spin_unlock(&xenbus_valloc_lock);
 
@@ -698,7 +698,7 @@ int xenbus_unmap_ring(struct xenbus_device *dev,
 {
 	struct gnttab_unmap_grant_ref op;
 
-	gnttab_set_unmap_op(&op, (phys_addr_t)vaddr, GNTMAP_host_map, handle);
+	gnttab_set_unmap_op(&op, (unsigned long)vaddr, GNTMAP_host_map, handle);
 
 	if (HYPERVISOR_grant_table_op(GNTTABOP_unmap_grant_ref, &op, 1))
 		BUG();
diff --git a/drivers/xen/xenbus/xenbus_dev_frontend.c b/drivers/xen/xenbus/xenbus_dev_frontend.c
index 527dc2a3b89f..89f76252a16f 100644
--- a/drivers/xen/xenbus/xenbus_dev_frontend.c
+++ b/drivers/xen/xenbus/xenbus_dev_frontend.c
@@ -369,6 +369,10 @@ static int xenbus_write_watch(unsigned msg_type, struct xenbus_file_priv *u)
 		goto out;
 	}
 	token++;
+	if (memchr(token, 0, u->u.msg.len - (token - path)) == NULL) {
+		rc = -EILSEQ;
+		goto out;
+	}
 
 	if (msg_type == XS_WATCH) {
 		watch = alloc_watch_adapter(path, token);
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 3864967202b5..b793723e724d 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -257,11 +257,12 @@ int xenbus_dev_remove(struct device *_dev)
 	DPRINTK("%s", dev->nodename);
 
 	free_otherend_watch(dev);
-	free_otherend_details(dev);
 
 	if (drv->remove)
 		drv->remove(dev);
 
+	free_otherend_details(dev);
+
 	xenbus_switch_state(dev, XenbusStateClosed);
 	return 0;
 }
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c
index 9c57819df51a..f20c5f178b40 100644
--- a/drivers/xen/xenbus/xenbus_probe_frontend.c
+++ b/drivers/xen/xenbus/xenbus_probe_frontend.c
@@ -53,6 +53,12 @@ static int xenbus_probe_frontend(struct xen_bus_type *bus, const char *type,
 	char *nodename;
 	int err;
 
+	/* ignore console/0 */
+	if (!strncmp(type, "console", 7) && !strncmp(name, "0", 1)) {
+		DPRINTK("Ignoring buggy device entry console/0");
+		return 0;
+	}
+
 	nodename = kasprintf(GFP_KERNEL, "%s/%s/%s", bus->root, type, name);
 	if (!nodename)
 		return -ENOMEM;