Drivers: hv: Miscellaneous fixes.

index db4b887..bbdec50 100644
@@ -275,7 +275,8 @@ void hv_fcopy_onchannelcallback(void *context)
 		 * Send the information to the user-level daemon.
 		 */
 		schedule_work(&fcopy_send_work);
-		schedule_delayed_work(&fcopy_timeout_work, 5*HZ);
+		schedule_delayed_work(&fcopy_timeout_work,
+				      HV_UTIL_TIMEOUT * HZ);
 		return;
 	}
 	icmsghdr->icflags = ICMSGHDRFLAG_TRANSACTION | ICMSGHDRFLAG_RESPONSE;

index 74c38a9..e6aa33a 100644
@@ -668,7 +668,8 @@ void hv_kvp_onchannelcallback(void *context)
 			 * user-mode not responding.
 			 */
 			schedule_work(&kvp_sendkey_work);
-			schedule_delayed_work(&kvp_timeout_work, 5*HZ);
+			schedule_delayed_work(&kvp_timeout_work,
+					      HV_UTIL_TIMEOUT * HZ);
 
 			return;
 

index 3782636..225b96b 100644
@@ -31,6 +31,11 @@
 #include <linux/hyperv.h>
 
 /*
+ * Timeout for services such as KVP and fcopy.
+ */
+#define HV_UTIL_TIMEOUT 30
+
+/*
  * The below CPUID leaves are present if VersionAndFeatures.HypervisorPresent
  * is set by CPUID(HVCPUID_VERSION_FEATURES).
  */

index bbdec50..c37a71e 100644
@@ -51,7 +51,6 @@ static struct {
 	struct hv_fcopy_hdr  *fcopy_msg; /* current message */
 	struct vmbus_channel *recv_channel; /* chn we got the request */
 	u64 recv_req_id; /* request ID. */
-	void *fcopy_context; /* for the channel callback */
 } fcopy_transaction;
 
 static void fcopy_respond_to_host(int error);

@@ -67,6 +66,13 @@ static struct hvutil_transport *hvt;
  */
 static int dm_reg_value;
 
+static void fcopy_poll_wrapper(void *channel)
+{
+	/* Transaction is finished, reset the state here to avoid races. */
+	fcopy_transaction.state = HVUTIL_READY;
+	hv_fcopy_onchannelcallback(channel);
+}
+
 static void fcopy_timeout_func(struct work_struct *dummy)
 {
 	/*

@@ -74,13 +80,7 @@ static void fcopy_timeout_func(struct work_struct *dummy)
 	 * process the pending transaction.
 	 */
 	fcopy_respond_to_host(HV_E_FAIL);
-
-	/* Transaction is finished, reset the state. */
-	if (fcopy_transaction.state > HVUTIL_READY)
-		fcopy_transaction.state = HVUTIL_READY;
-
-	hv_poll_channel(fcopy_transaction.fcopy_context,
-			hv_fcopy_onchannelcallback);
+	hv_poll_channel(fcopy_transaction.recv_channel, fcopy_poll_wrapper);
 }
 
 static int fcopy_handle_handshake(u32 version)

@@ -108,9 +108,7 @@ static int fcopy_handle_handshake(u32 version)
 		return -EINVAL;
 	}
 	pr_debug("FCP: userspace daemon ver. %d registered\n", version);
-	fcopy_transaction.state = HVUTIL_READY;
-	hv_poll_channel(fcopy_transaction.fcopy_context,
-			hv_fcopy_onchannelcallback);
+	hv_poll_channel(fcopy_transaction.recv_channel, fcopy_poll_wrapper);
 	return 0;
 }
 

@@ -227,15 +225,8 @@ void hv_fcopy_onchannelcallback(void *context)
 	int util_fw_version;
 	int fcopy_srv_version;
 
-	if (fcopy_transaction.state > HVUTIL_READY) {
-		/*
-		 * We will defer processing this callback once
-		 * the current transaction is complete.
-		 */
-		fcopy_transaction.fcopy_context = context;
+	if (fcopy_transaction.state > HVUTIL_READY)
 		return;
-	}
-	fcopy_transaction.fcopy_context = NULL;
 
 	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
 			 &requestid);

@@ -305,9 +296,8 @@ static int fcopy_on_msg(void *msg, int len)
 	if (cancel_delayed_work_sync(&fcopy_timeout_work)) {
 		fcopy_transaction.state = HVUTIL_USERSPACE_RECV;
 		fcopy_respond_to_host(*val);
-		fcopy_transaction.state = HVUTIL_READY;
-		hv_poll_channel(fcopy_transaction.fcopy_context,
-				hv_fcopy_onchannelcallback);
+		hv_poll_channel(fcopy_transaction.recv_channel,
+				fcopy_poll_wrapper);
 	}
 
 	return 0;

index e6aa33a..2a3420c 100644
@@ -66,7 +66,6 @@ static struct {
 	struct hv_kvp_msg  *kvp_msg; /* current message */
 	struct vmbus_channel *recv_channel; /* chn we got the request */
 	u64 recv_req_id; /* request ID. */
-	void *kvp_context; /* for the channel callback */
 } kvp_transaction;
 
 /*

@@ -94,6 +93,13 @@ static struct hvutil_transport *hvt;
  */
 #define HV_DRV_VERSION           "3.1"
 
+static void kvp_poll_wrapper(void *channel)
+{
+	/* Transaction is finished, reset the state here to avoid races. */
+	kvp_transaction.state = HVUTIL_READY;
+	hv_kvp_onchannelcallback(channel);
+}
+
 static void
 kvp_register(int reg_value)
 {

@@ -121,12 +127,7 @@ static void kvp_timeout_func(struct work_struct *dummy)
 	 */
 	kvp_respond_to_host(NULL, HV_E_FAIL);
 
-	/* Transaction is finished, reset the state. */
-	if (kvp_transaction.state > HVUTIL_READY)
-		kvp_transaction.state = HVUTIL_READY;
-
-	hv_poll_channel(kvp_transaction.kvp_context,
-			hv_kvp_onchannelcallback);
+	hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
 }
 
 static int kvp_handle_handshake(struct hv_kvp_msg *msg)

@@ -218,9 +219,7 @@ static int kvp_on_msg(void *msg, int len)
 	 */
 	if (cancel_delayed_work_sync(&kvp_timeout_work)) {
 		kvp_respond_to_host(message, error);
-		kvp_transaction.state = HVUTIL_READY;
-		hv_poll_channel(kvp_transaction.kvp_context,
-				hv_kvp_onchannelcallback);
+		hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
 	}
 
 	return 0;

@@ -596,15 +595,8 @@ void hv_kvp_onchannelcallback(void *context)
 	int util_fw_version;
 	int kvp_srv_version;
 
-	if (kvp_transaction.state > HVUTIL_READY) {
-		/*
-		 * We will defer processing this callback once
-		 * the current transaction is complete.
-		 */
-		kvp_transaction.kvp_context = context;
+	if (kvp_transaction.state > HVUTIL_READY)
 		return;
-	}
-	kvp_transaction.kvp_context = NULL;
 
 	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 4, &recvlen,
 			 &requestid);

index 815405f..a548ae4 100644
@@ -53,7 +53,6 @@ static struct {
 	struct vmbus_channel *recv_channel; /* chn we got the request */
 	u64 recv_req_id; /* request ID. */
 	struct hv_vss_msg  *msg; /* current message */
-	void *vss_context; /* for the channel callback */
 } vss_transaction;
 
 

@@ -74,6 +73,13 @@ static void vss_timeout_func(struct work_struct *dummy);
 static DECLARE_DELAYED_WORK(vss_timeout_work, vss_timeout_func);
 static DECLARE_WORK(vss_send_op_work, vss_send_op);
 
+static void vss_poll_wrapper(void *channel)
+{
+	/* Transaction is finished, reset the state here to avoid races. */
+	vss_transaction.state = HVUTIL_READY;
+	hv_vss_onchannelcallback(channel);
+}
+
 /*
  * Callback when data is received from user mode.
  */

@@ -86,12 +92,7 @@ static void vss_timeout_func(struct work_struct *dummy)
 	pr_warn("VSS: timeout waiting for daemon to reply\n");
 	vss_respond_to_host(HV_E_FAIL);
 
-	/* Transaction is finished, reset the state. */
-	if (vss_transaction.state > HVUTIL_READY)
-		vss_transaction.state = HVUTIL_READY;
-
-	hv_poll_channel(vss_transaction.vss_context,
-			hv_vss_onchannelcallback);
+	hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper);
 }
 
 static int vss_handle_handshake(struct hv_vss_msg *vss_msg)

@@ -138,9 +139,8 @@ static int vss_on_msg(void *msg, int len)
 		if (cancel_delayed_work_sync(&vss_timeout_work)) {
 			vss_respond_to_host(vss_msg->error);
 			/* Transaction is finished, reset the state. */
-			vss_transaction.state = HVUTIL_READY;
-			hv_poll_channel(vss_transaction.vss_context,
-					hv_vss_onchannelcallback);
+			hv_poll_channel(vss_transaction.recv_channel,
+					vss_poll_wrapper);
 		}
 	} else {
 		/* This is a spurious call! */

@@ -238,15 +238,8 @@ void hv_vss_onchannelcallback(void *context)
 	struct icmsg_hdr *icmsghdrp;
 	struct icmsg_negotiate *negop = NULL;
 
-	if (vss_transaction.state > HVUTIL_READY) {
-		/*
-		 * We will defer processing this callback once
-		 * the current transaction is complete.
-		 */
-		vss_transaction.vss_context = context;
+	if (vss_transaction.state > HVUTIL_READY)
 		return;
-	}
-	vss_transaction.vss_context = NULL;
 
 	vmbus_recvpacket(channel, recv_buffer, PAGE_SIZE * 2, &recvlen,
 			 &requestid);

index 225b96b..12156db 100644
@@ -764,11 +764,7 @@ static inline void hv_poll_channel(struct vmbus_channel *channel,
 	if (!channel)
 		return;
 
-	if (channel->target_cpu != smp_processor_id())
-		smp_call_function_single(channel->target_cpu,
-					 cb, channel, true);
-	else
-		cb(channel);
+	smp_call_function_single(channel->target_cpu, cb, channel, true);
 }
 
 enum hvutil_device_state {

index e4c0a35..e347b24 100644
@@ -313,6 +313,7 @@ enum hv_kvp_exchg_pool {
 #define HV_INVALIDARG			0x80070057
 #define HV_GUID_NOTFOUND		0x80041002
 #define HV_ERROR_ALREADY_EXISTS		0x80070050
+#define HV_ERROR_DISK_FULL		0x80070070
 
 #define ADDR_FAMILY_NONE	0x00
 #define ADDR_FAMILY_IPV4	0x01

index 5480e4e..f1d7426 100644
@@ -37,12 +37,14 @@
 
 static int target_fd;
 static char target_fname[W_MAX_PATH];
+static unsigned long long filesize;
 
 static int hv_start_fcopy(struct hv_start_fcopy *smsg)
 {
 	int error = HV_E_FAIL;
 	char *q, *p;
 
+	filesize = 0;
 	p = (char *)smsg->path_name;
 	snprintf(target_fname, sizeof(target_fname), "%s/%s",
 		 (char *)smsg->path_name, (char *)smsg->file_name);

@@ -98,14 +100,26 @@ done:
 static int hv_copy_data(struct hv_do_fcopy *cpmsg)
 {
 	ssize_t bytes_written;
+	int ret = 0;
 
 	bytes_written = pwrite(target_fd, cpmsg->data, cpmsg->size,
 				cpmsg->offset);
 
-	if (bytes_written != cpmsg->size)
-		return HV_E_FAIL;
+	filesize += cpmsg->size;
+	if (bytes_written != cpmsg->size) {
+		switch (errno) {
+		case ENOSPC:
+			ret = HV_ERROR_DISK_FULL;
+			break;
+		default:
+			ret = HV_E_FAIL;
+			break;
+		}
+		syslog(LOG_ERR, "pwrite failed to write %llu bytes: %ld (%s)",
+		       filesize, (long)bytes_written, strerror(errno));
+	}
 
-	return 0;
+	return ret;
 }
 
 static int hv_copy_finished(void)

index f1d7426..fdc9ca4 100644
@@ -179,7 +179,7 @@ int main(int argc, char *argv[])
 	}
 
 	openlog("HV_FCOPY", 0, LOG_USER);
-	syslog(LOG_INFO, "HV_FCOPY starting; pid is:%d", getpid());
+	syslog(LOG_INFO, "starting; pid is:%d", getpid());
 
 	fcopy_fd = open("/dev/vmbus/hv_fcopy", O_RDWR);
 

@@ -215,7 +215,7 @@ int main(int argc, char *argv[])
 			}
 			kernel_modver = *(__u32 *)buffer;
 			in_handshake = 0;
-			syslog(LOG_INFO, "HV_FCOPY: kernel module version: %d",
+			syslog(LOG_INFO, "kernel module version: %d",
 			       kernel_modver);
 			continue;
 		}

index 6a9d80a..1505ee6 100644
@@ -204,9 +204,12 @@ int hvutil_transport_send(struct hvutil_transport *hvt, void *msg, int len)
 		goto out_unlock;
 	}
 	hvt->outmsg = kzalloc(len, GFP_KERNEL);
-	memcpy(hvt->outmsg, msg, len);
-	hvt->outmsg_len = len;
-	wake_up_interruptible(&hvt->outmsg_q);
+	if (hvt->outmsg) {
+		memcpy(hvt->outmsg, msg, len);
+		hvt->outmsg_len = len;
+		wake_up_interruptible(&hvt->outmsg_q);
+	} else
+		ret = -ENOMEM;
 out_unlock:
 	mutex_unlock(&hvt->outmsg_lock);
 	return ret;

index 1505ee6..24b2766 100644
@@ -80,11 +80,10 @@ static ssize_t hvt_op_write(struct file *file, const char __user *buf,
 
 	hvt = container_of(file->f_op, struct hvutil_transport, fops);
 
-	inmsg = kzalloc(count, GFP_KERNEL);
-	if (copy_from_user(inmsg, buf, count)) {
-		kfree(inmsg);
-		return -EFAULT;
-	}
+	inmsg = memdup_user(buf, count);
+	if (IS_ERR(inmsg))
+		return PTR_ERR(inmsg);
+
 	if (hvt->on_msg(inmsg, count))
 		return -EFAULT;
 	kfree(inmsg);

index f19b6f7..3297731 100644
@@ -867,7 +867,7 @@ static int vmbus_bus_init(int irq)
 	on_each_cpu(hv_synic_init, NULL, 1);
 	ret = vmbus_connect();
 	if (ret)
-		goto err_alloc;
+		goto err_connect;
 
 	if (vmbus_proto_version > VERSION_WIN7)
 		cpu_hotplug_disable();

@@ -885,6 +885,8 @@ static int vmbus_bus_init(int irq)
 
 	return 0;
 
+err_connect:
+	on_each_cpu(hv_synic_cleanup, NULL, 1);
 err_alloc:
 	hv_synic_free();
 	hv_remove_vmbus_irq();

index 3297731..c01b689 100644
@@ -1193,6 +1193,23 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
 }
 EXPORT_SYMBOL_GPL(vmbus_allocate_mmio);
 
+/**
+ * vmbus_cpu_number_to_vp_number() - Map CPU to VP.
+ * @cpu_number: CPU number in Linux terms
+ *
+ * This function returns the mapping between the Linux processor
+ * number and the hypervisor's virtual processor number, useful
+ * in making hypercalls and such that talk about specific
+ * processors.
+ *
+ * Return: Virtual processor number in Hyper-V terms
+ */
+int vmbus_cpu_number_to_vp_number(int cpu_number)
+{
+	return hv_context.vp_index[cpu_number];
+}
+EXPORT_SYMBOL_GPL(vmbus_cpu_number_to_vp_number);
+
 static int vmbus_acpi_add(struct acpi_device *device)
 {
 	acpi_status result;

index 8fdc17b..fddb3e0 100644
@@ -983,6 +983,8 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
 			resource_size_t size, resource_size_t align,
 			bool fb_overlap_ok);
 
+int vmbus_cpu_number_to_vp_number(int cpu_number);
+
 /**
  * VMBUS_DEVICE - macro used to describe a specific hyperv vmbus device
  *

index 6341be8..7a06933 100644
@@ -89,9 +89,9 @@ static int query_hypervisor_info(void)
 }
 
 /*
- * do_hypercall- Invoke the specified hypercall
+ * hv_do_hypercall- Invoke the specified hypercall
  */
-static u64 do_hypercall(u64 control, void *input, void *output)
+u64 hv_do_hypercall(u64 control, void *input, void *output)
 {
 	u64 input_address = (input) ? virt_to_phys(input) : 0;
 	u64 output_address = (output) ? virt_to_phys(output) : 0;

@@ -132,6 +132,7 @@ static u64 do_hypercall(u64 control, void *input, void *output)
 	return hv_status_lo | ((u64)hv_status_hi << 32);
 #endif /* !x86_64 */
 }
+EXPORT_SYMBOL_GPL(hv_do_hypercall);
 
 #ifdef CONFIG_X86_64
 static cycle_t read_hv_clock_tsc(struct clocksource *arg)

@@ -315,7 +316,7 @@ int hv_post_message(union hv_connection_id connection_id,
 {
 
 	struct hv_input_post_message *aligned_msg;
-	u16 status;
+	u64 status;
 
 	if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
 		return -EMSGSIZE;

@@ -329,11 +330,10 @@ int hv_post_message(union hv_connection_id connection_id,
 	aligned_msg->payload_size = payload_size;
 	memcpy((void *)aligned_msg->payload, payload, payload_size);
 
-	status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
-		& 0xFFFF;
+	status = hv_do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL);
 
 	put_cpu();
-	return status;
+	return status & 0xFFFF;
 }
 
 

@@ -343,13 +343,13 @@ int hv_post_message(union hv_connection_id connection_id,
  *
  * This involves a hypercall.
  */
-u16 hv_signal_event(void *con_id)
+int hv_signal_event(void *con_id)
 {
-	u16 status;
+	u64 status;
 
-	status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF);
+	status = hv_do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL);
 
-	return status;
+	return status & 0xFFFF;
 }
 
 static int hv_ce_set_next_event(unsigned long delta,

index 12156db..9beeb14 100644
@@ -587,7 +587,7 @@ extern int hv_post_message(union hv_connection_id connection_id,
 			 enum hv_message_type message_type,
 			 void *payload, size_t payload_size);
 
-extern u16 hv_signal_event(void *con_id);
+extern int hv_signal_event(void *con_id);
 
 extern int hv_synic_alloc(void);
 

index fddb3e0..24d0b65 100644
@@ -984,6 +984,7 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
 			bool fb_overlap_ok);
 
 int vmbus_cpu_number_to_vp_number(int cpu_number);
+u64 hv_do_hypercall(u64 control, void *input, void *output);
 
 /**
  * VMBUS_DEVICE - macro used to describe a specific hyperv vmbus device

index 652afd1..a77646b 100644
@@ -358,6 +358,7 @@ enum {
 	SCSI,
 	NIC,
 	ND_NIC,
+	PCIE,
 	MAX_PERF_CHN,
 };
 

@@ -375,6 +376,8 @@ static const struct hv_vmbus_device_id hp_devs[] = {
 	{ HV_NIC_GUID, },
 	/* NetworkDirect Guest RDMA */
 	{ HV_ND_GUID, },
+	/* PCI Express Pass Through */
+	{ HV_PCIE_GUID, },
 };
 
 

index 24d0b65..c9a9eed 100644
@@ -1141,6 +1141,17 @@ u64 hv_do_hypercall(u64 control, void *input, void *output);
 		}
 
 /*
+ * PCI Express Pass Through
+ * {44C4F61D-4444-4400-9D52-802E27EDE19F}
+ */
+
+#define HV_PCIE_GUID \
+	.guid = { \
+			0x1D, 0xF6, 0xC4, 0x44, 0x44, 0x44, 0x00, 0x44, \
+			0x9D, 0x52, 0x80, 0x2E, 0x27, 0xED, 0xE1, 0x9F \
+		}
+
+/*
  * Common header for Hyper-V ICs
  */
 

index a548ae4..81882d4 100644
@@ -331,6 +331,11 @@ static void vss_on_reset(void)
 int
 hv_vss_init(struct hv_util_service *srv)
 {
+	if (vmbus_proto_version < VERSION_WIN8_1) {
+		pr_warn("Integration service 'Backup (volume snapshot)'"
+			" not supported on this host version.\n");
+		return -ENOTSUPP;
+	}
 	recv_buffer = srv->recv_buffer;
 
 	/*

index a77646b..38470aa 100644
@@ -408,7 +408,7 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui
 	struct cpumask *alloced_mask;
 
 	for (i = IDE; i < MAX_PERF_CHN; i++) {
-		if (!memcmp(type_guid->b, hp_devs[i].guid,
+		if (!memcmp(type_guid->b, &hp_devs[i].guid,
 				 sizeof(uuid_le))) {
 			perf_chn = true;
 			break;

index c01b689..7078b5f 100644
@@ -531,7 +531,7 @@ static int vmbus_uevent(struct device *device, struct kobj_uevent_env *env)
 
 static const uuid_le null_guid;
 
-static inline bool is_null_guid(const __u8 *guid)
+static inline bool is_null_guid(const uuid_le *guid)
 {
 	if (memcmp(guid, &null_guid, sizeof(uuid_le)))
 		return false;

@@ -544,9 +544,9 @@ static inline bool is_null_guid(const __u8 *guid)
  */
 static const struct hv_vmbus_device_id *hv_vmbus_get_id(
 					const struct hv_vmbus_device_id *id,
-					const __u8 *guid)
+					const uuid_le *guid)
 {
-	for (; !is_null_guid(id->guid); id++)
+	for (; !is_null_guid(&id->guid); id++)
 		if (!memcmp(&id->guid, guid, sizeof(uuid_le)))
 			return id;
 

@@ -563,7 +563,7 @@ static int vmbus_match(struct device *device, struct device_driver *driver)
 	struct hv_driver *drv = drv_to_hv_drv(driver);
 	struct hv_device *hv_dev = device_to_hv_device(device);
 
-	if (hv_vmbus_get_id(drv->id_table, hv_dev->dev_type.b))
+	if (hv_vmbus_get_id(drv->id_table, &hv_dev->dev_type))
 		return 1;
 
 	return 0;

@@ -580,7 +580,7 @@ static int vmbus_probe(struct device *child_device)
 	struct hv_device *dev = device_to_hv_device(child_device);
 	const struct hv_vmbus_device_id *dev_id;
 
-	dev_id = hv_vmbus_get_id(drv->id_table, dev->dev_type.b);
+	dev_id = hv_vmbus_get_id(drv->id_table, &dev->dev_type);
 	if (drv->probe) {
 		ret = drv->probe(dev, dev_id);
 		if (ret != 0)

186 lines not on this page · raw message

index 64f36e0..6e4c645 100644
@@ -404,7 +404,7 @@ struct virtio_device_id {
  * For Hyper-V devices we use the device guid as the id.
  */
 struct hv_vmbus_device_id {
-	__u8 guid[16];
+	uuid_le guid;
 	kernel_ulong_t driver_data;	/* Data private to the driver */
 };
 

index 5b96206..8adca44 100644
@@ -917,7 +917,7 @@ static int do_vmbus_entry(const char *filename, void *symval,
 	char guid_name[(sizeof(*guid) + 1) * 2];
 
 	for (i = 0; i < (sizeof(*guid) * 2); i += 2)
-		sprintf(&guid_name[i], "%02x", TO_NATIVE((*guid)[i/2]));
+		sprintf(&guid_name[i], "%02x", TO_NATIVE((guid->b)[i/2]));
 
 	strcpy(alias, "vmbus:");
 	strcat(alias, guid_name);

index 38470aa..dc4fb0b 100644
@@ -408,8 +408,7 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui
 	struct cpumask *alloced_mask;
 
 	for (i = IDE; i < MAX_PERF_CHN; i++) {
-		if (!memcmp(type_guid->b, &hp_devs[i].guid,
-				 sizeof(uuid_le))) {
+		if (!uuid_le_cmp(*type_guid, hp_devs[i].guid)) {
 			perf_chn = true;
 			break;
 		}

index 7078b5f..9e0e25c 100644
@@ -533,7 +533,7 @@ static const uuid_le null_guid;
 
 static inline bool is_null_guid(const uuid_le *guid)
 {
-	if (memcmp(guid, &null_guid, sizeof(uuid_le)))
+	if (uuid_le_cmp(*guid, null_guid))
 		return false;
 	return true;
 }

@@ -547,7 +547,7 @@ static const struct hv_vmbus_device_id *hv_vmbus_get_id(
 					const uuid_le *guid)
 {
 	for (; !is_null_guid(&id->guid); id++)
-		if (!memcmp(&id->guid, guid, sizeof(uuid_le)))
+		if (!uuid_le_cmp(id->guid, *guid))
 			return id;
 
 	return NULL;

index b9f3bb2..f773a68 100644
@@ -986,19 +986,6 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
 int vmbus_cpu_number_to_vp_number(int cpu_number);
 u64 hv_do_hypercall(u64 control, void *input, void *output);
 
-/**
- * VMBUS_DEVICE - macro used to describe a specific hyperv vmbus device
- *
- * This macro is used to create a struct hv_vmbus_device_id that matches a
- * specific device.
- */
-#define VMBUS_DEVICE(g0, g1, g2, g3, g4, g5, g6, g7,	\
-		     g8, g9, ga, gb, gc, gd, ge, gf)	\
-	.guid = { g0, g1, g2, g3, g4, g5, g6, g7,	\
-		  g8, g9, ga, gb, gc, gd, ge, gf },
-
-
-
 /*
  * GUID definitions of various offer types - services offered to the guest.
  */

index 9e0e25c..ab888a1 100644
@@ -47,7 +47,6 @@ static struct acpi_device  *hv_acpi_dev;
 
 static struct tasklet_struct msg_dpc;
 static struct completion probe_event;
-static int irq;
 
 
 static void hyperv_report_panic(struct pt_regs *regs)

@@ -835,10 +834,9 @@ static void vmbus_isr(void)
  * Here, we
  *	- initialize the vmbus driver context
  *	- invoke the vmbus hv main init routine
- *	- get the irq resource
  *	- retrieve the channel offers
  */
-static int vmbus_bus_init(int irq)
+static int vmbus_bus_init(void)
 {
 	int ret;
 

@@ -1033,9 +1031,6 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
 	struct resource **prev_res = NULL;
 
 	switch (res->type) {
-	case ACPI_RESOURCE_TYPE_IRQ:
-		irq = res->data.irq.interrupts[0];
-		return AE_OK;
 
 	/*
 	 * "Address" descriptors are for bus windows. Ignore

@@ -1294,7 +1289,7 @@ static int __init hv_acpi_init(void)
 	init_completion(&probe_event);
 
 	/*
-	 * Get irq resources first.
+	 * Get ACPI resources first.
 	 */
 	ret = acpi_bus_register_driver(&vmbus_acpi_driver);
 

@@ -1307,12 +1302,7 @@ static int __init hv_acpi_init(void)
 		goto cleanup;
 	}
 
-	if (irq <= 0) {
-		ret = -ENODEV;
-		goto cleanup;
-	}
-
-	ret = vmbus_bus_init(irq);
+	ret = vmbus_bus_init();
 	if (ret)
 		goto cleanup;
 

index c4dcab0..f7f3d5c 100644
@@ -28,6 +28,7 @@
 #include <linux/module.h>
 #include <linux/hyperv.h>
 #include <linux/uio.h>
+#include <linux/interrupt.h>
 
 #include "hyperv_vmbus.h"
 

@@ -496,8 +497,21 @@ static void reset_channel_cb(void *arg)
 static int vmbus_close_internal(struct vmbus_channel *channel)
 {
 	struct vmbus_channel_close_channel *msg;
+	struct tasklet_struct *tasklet;
 	int ret;
 
+	/*
+	 * process_chn_event(), running in the tasklet, can race
+	 * with vmbus_close_internal() in the case of SMP guest, e.g., when
+	 * the former is accessing channel->inbound.ring_buffer, the latter
+	 * could be freeing the ring_buffer pages.
+	 *
+	 * To resolve the race, we can serialize them by disabling the
+	 * tasklet when the latter is running here.
+	 */
+	tasklet = hv_context.event_dpc[channel->target_cpu];
+	tasklet_disable(tasklet);
+
 	channel->state = CHANNEL_OPEN_STATE;
 	channel->sc_creation_callback = NULL;
 	/* Stop callback and cancel the timer asap */

@@ -525,7 +539,7 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 		 * If we failed to post the close msg,
 		 * it is perhaps better to leak memory.
 		 */
-		return ret;
+		goto out;
 	}
 
 	/* Tear down the gpadl for the channel's ring buffer */

@@ -538,7 +552,7 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 			 * If we failed to teardown gpadl,
 			 * it is perhaps better to leak memory.
 			 */
-			return ret;
+			goto out;
 		}
 	}
 

@@ -555,6 +569,9 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 	if (channel->rescind)
 		hv_process_channel_removal(channel,
 					   channel->offermsg.child_relid);
+out:
+	tasklet_enable(tasklet);
+
 	return ret;
 }
 

index f7f3d5c..00e1be7 100644
@@ -512,6 +512,18 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 	tasklet = hv_context.event_dpc[channel->target_cpu];
 	tasklet_disable(tasklet);
 
+	/*
+	 * In case a device driver's probe() fails (e.g.,
+	 * util_probe() -> vmbus_open() returns -ENOMEM) and the device is
+	 * rescinded later (e.g., we dynamically disble an Integrated Service
+	 * in Hyper-V Manager), the driver's remove() invokes vmbus_close():
+	 * here we should skip most of the below cleanup work.
+	 */
+	if (channel->state != CHANNEL_OPENED_STATE) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	channel->state = CHANNEL_OPEN_STATE;
 	channel->sc_creation_callback = NULL;
 	/* Stop callback and cancel the timer asap */

index 00e1be7..77d2579 100644
@@ -575,12 +575,6 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 	free_pages((unsigned long)channel->ringbuffer_pages,
 		get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
 
-	/*
-	 * If the channel has been rescinded; process device removal.
-	 */
-	if (channel->rescind)
-		hv_process_channel_removal(channel,
-					   channel->offermsg.child_relid);
 out:
 	tasklet_enable(tasklet);
 

index dc4fb0b..7903acc 100644
@@ -191,6 +191,8 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
 	if (channel == NULL)
 		return;
 
+	BUG_ON(!channel->rescind);
+
 	if (channel->target_cpu != get_cpu()) {
 		put_cpu();
 		smp_call_function_single(channel->target_cpu,

@@ -230,9 +232,7 @@ void vmbus_free_channels(void)
 
 	list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list,
 		listentry) {
-		/* if we don't set rescind to true, vmbus_close_internal()
-		 * won't invoke hv_process_channel_removal().
-		 */
+		/* hv_process_channel_removal() needs this */
 		channel->rescind = true;
 
 		vmbus_device_unregister(channel->device_obj);

index ab888a1..f123bca 100644
@@ -601,23 +601,11 @@ static int vmbus_remove(struct device *child_device)
 {
 	struct hv_driver *drv;
 	struct hv_device *dev = device_to_hv_device(child_device);
-	u32 relid = dev->channel->offermsg.child_relid;
 
 	if (child_device->driver) {
 		drv = drv_to_hv_drv(child_device->driver);
 		if (drv->remove)
 			drv->remove(dev);
-		else {
-			hv_process_channel_removal(dev->channel, relid);
-			pr_err("remove not set for driver %s\n",
-				dev_name(child_device));
-		}
-	} else {
-		/*
-		 * We don't have a driver for this device; deal with the
-		 * rescind message by removing the channel.
-		 */
-		hv_process_channel_removal(dev->channel, relid);
 	}
 
 	return 0;

@@ -652,7 +640,10 @@ static void vmbus_shutdown(struct device *child_device)
 static void vmbus_device_release(struct device *device)
 {
 	struct hv_device *hv_dev = device_to_hv_device(device);
+	struct vmbus_channel *channel = hv_dev->channel;
 
+	hv_process_channel_removal(channel,
+				   channel->offermsg.child_relid);
 	kfree(hv_dev);
 
 }

index 7903acc..9c9da3a 100644
@@ -177,19 +177,22 @@ static void percpu_channel_deq(void *arg)
 }
 
 
-void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+static void vmbus_release_relid(u32 relid)
 {
 	struct vmbus_channel_relid_released msg;
-	unsigned long flags;
-	struct vmbus_channel *primary_channel;
 
 	memset(&msg, 0, sizeof(struct vmbus_channel_relid_released));
 	msg.child_relid = relid;
 	msg.header.msgtype = CHANNELMSG_RELID_RELEASED;
 	vmbus_post_msg(&msg, sizeof(struct vmbus_channel_relid_released));
+}
 
-	if (channel == NULL)
-		return;
+void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+{
+	unsigned long flags;
+	struct vmbus_channel *primary_channel;
+
+	vmbus_release_relid(relid);
 
 	BUG_ON(!channel->rescind);
 

@@ -336,6 +339,8 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 	return;
 
 err_deq_chan:
+	vmbus_release_relid(newchannel->offermsg.child_relid);
+
 	spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
 	list_del(&newchannel->listentry);
 	spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);

@@ -587,7 +592,11 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
 	channel = relid2channel(rescind->child_relid);
 
 	if (channel == NULL) {
-		hv_process_channel_removal(NULL, rescind->child_relid);
+		/*
+		 * This is very impossible, because in
+		 * vmbus_process_offer(), we have already invoked
+		 * vmbus_release_relid() on error.
+		 */
 		return;
 	}
 

index 9c9da3a..d013171 100644
@@ -206,9 +206,9 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
 	}
 
 	if (channel->primary_channel == NULL) {
-		spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+		mutex_lock(&vmbus_connection.channel_mutex);
 		list_del(&channel->listentry);
-		spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+		mutex_unlock(&vmbus_connection.channel_mutex);
 
 		primary_channel = channel;
 	} else {

@@ -253,7 +253,7 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 	unsigned long flags;
 
 	/* Make sure this is a new offer */
-	spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+	mutex_lock(&vmbus_connection.channel_mutex);
 
 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 		if (!uuid_le_cmp(channel->offermsg.offer.if_type,

@@ -269,7 +269,7 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 		list_add_tail(&newchannel->listentry,
 			      &vmbus_connection.chn_list);
 
-	spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+	mutex_unlock(&vmbus_connection.channel_mutex);
 
 	if (!fnew) {
 		/*

@@ -341,9 +341,9 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
 err_deq_chan:
 	vmbus_release_relid(newchannel->offermsg.child_relid);
 
-	spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+	mutex_lock(&vmbus_connection.channel_mutex);
 	list_del(&newchannel->listentry);
-	spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+	mutex_unlock(&vmbus_connection.channel_mutex);
 
 	if (newchannel->target_cpu != get_cpu()) {
 		put_cpu();

index 4fc2e88..521f48e 100644
@@ -146,7 +146,7 @@ int vmbus_connect(void)
 	spin_lock_init(&vmbus_connection.channelmsg_lock);
 
 	INIT_LIST_HEAD(&vmbus_connection.chn_list);
-	spin_lock_init(&vmbus_connection.channel_lock);
+	mutex_init(&vmbus_connection.channel_mutex);
 
 	/*
 	 * Setup the vmbus event connection for channel interrupt

@@ -282,11 +282,10 @@ struct vmbus_channel *relid2channel(u32 relid)
 {
 	struct vmbus_channel *channel;
 	struct vmbus_channel *found_channel  = NULL;
-	unsigned long flags;
 	struct list_head *cur, *tmp;
 	struct vmbus_channel *cur_sc;
 
-	spin_lock_irqsave(&vmbus_connection.channel_lock, flags);
+	mutex_lock(&vmbus_connection.channel_mutex);
 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
 		if (channel->offermsg.child_relid == relid) {
 			found_channel = channel;

@@ -305,7 +304,7 @@ struct vmbus_channel *relid2channel(u32 relid)
 			}
 		}
 	}
-	spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags);
+	mutex_unlock(&vmbus_connection.channel_mutex);
 
 	return found_channel;
 }

index 9beeb14..4d67e98 100644
@@ -683,7 +683,7 @@ struct vmbus_connection {
 
 	/* List of channels */
 	struct list_head chn_list;
-	spinlock_t channel_lock;
+	struct mutex channel_mutex;
 
 	struct workqueue_struct *work_queue;
 };

index f123bca..328e4c3 100644
@@ -1063,12 +1063,28 @@ static acpi_status vmbus_walk_resources(struct acpi_resource *res, void *ctx)
 	new_res->start = start;
 	new_res->end = end;
 
+	/*
+	 * Stick ranges from higher in address space at the front of the list.
+	 * If two ranges are adjacent, merge them.
+	 */
 	do {
 		if (!*old_res) {
 			*old_res = new_res;
 			break;
 		}
 
+		if (((*old_res)->end + 1) == new_res->start) {
+			(*old_res)->end = new_res->end;
+			kfree(new_res);
+			break;
+		}
+
+		if ((*old_res)->start == new_res->end + 1) {
+			(*old_res)->start = new_res->start;
+			kfree(new_res);
+			break;
+		}
+
 		if ((*old_res)->end < new_res->start) {
 			new_res->sibling = *old_res;
 			if (prev_res)

index 77d2579..2889d97 100644
@@ -653,10 +653,19 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
 	 *    on the ring. We will not signal if more data is
 	 *    to be placed.
 	 *
+	 * Based on the channel signal state, we will decide
+	 * which signaling policy will be applied.
+	 *
 	 * If we cannot write to the ring-buffer; signal the host
 	 * even if we may not have written anything. This is a rare
 	 * enough condition that it should not matter.
 	 */
+
+	if (channel->signal_policy)
+		signal = true;
+	else
+		kick_q = true;
+
 	if (((ret == 0) && kick_q && signal) || (ret))
 		vmbus_setevent(channel);
 

@@ -756,10 +765,19 @@ int vmbus_sendpacket_pagebuffer_ctl(struct vmbus_channel *channel,
 	 *    on the ring. We will not signal if more data is
 	 *    to be placed.
 	 *
+	 * Based on the channel signal state, we will decide
+	 * which signaling policy will be applied.
+	 *
 	 * If we cannot write to the ring-buffer; signal the host
 	 * even if we may not have written anything. This is a rare
 	 * enough condition that it should not matter.
 	 */
+
+	if (channel->signal_policy)
+		signal = true;
+	else
+		kick_q = true;
+
 	if (((ret == 0) && kick_q && signal) || (ret))
 		vmbus_setevent(channel);
 

index f773a68..acd995b 100644
@@ -630,6 +630,11 @@ struct hv_input_signal_event_buffer {
 	struct hv_input_signal_event event;
 };
 
+enum hv_signal_policy {
+	HV_SIGNAL_POLICY_DEFAULT = 0,
+	HV_SIGNAL_POLICY_EXPLICIT,
+};
+
 struct vmbus_channel {
 	/* Unique channel id */
 	int id;

@@ -757,8 +762,21 @@ struct vmbus_channel {
 	 * link up channels based on their CPU affinity.
 	 */
 	struct list_head percpu_list;
+	/*
+	 * Host signaling policy: The default policy will be
+	 * based on the ring buffer state. We will also support
+	 * a policy where the client driver can have explicit
+	 * signaling control.
+	 */
+	enum hv_signal_policy  signal_policy;
 };
 
+static inline void set_channel_signal_state(struct vmbus_channel *c,
+					    enum hv_signal_policy policy)
+{
+	c->signal_policy = policy;
+}
+
 static inline void set_channel_read_state(struct vmbus_channel *c, bool state)
 {
 	c->batched_reading = state;

index 7a06933..1db9556 100644
@@ -140,7 +140,7 @@ static cycle_t read_hv_clock_tsc(struct clocksource *arg)
 	cycle_t current_tick;
 	struct ms_hyperv_tsc_page *tsc_pg = hv_context.tsc_page;
 
-	if (tsc_pg->tsc_sequence != -1) {
+	if (tsc_pg->tsc_sequence != 0) {
 		/*
 		 * Use the tsc page to compute the value.
 		 */

@@ -162,7 +162,7 @@ static cycle_t read_hv_clock_tsc(struct clocksource *arg)
 			if (tsc_pg->tsc_sequence == sequence)
 				return current_tick;
 
-			if (tsc_pg->tsc_sequence != -1)
+			if (tsc_pg->tsc_sequence != 0)
 				continue;
 			/*
 			 * Fallback using MSR method.

index 521f48e..3dc5a9c 100644
@@ -83,10 +83,13 @@ static int vmbus_negotiate_version(struct vmbus_channel_msginfo *msginfo,
 	msg->interrupt_page = virt_to_phys(vmbus_connection.int_page);
 	msg->monitor_page1 = virt_to_phys(vmbus_connection.monitor_pages[0]);
 	msg->monitor_page2 = virt_to_phys(vmbus_connection.monitor_pages[1]);
-	if (version >= VERSION_WIN8_1) {
-		msg->target_vcpu = hv_context.vp_index[get_cpu()];
-		put_cpu();
-	}
+	/*
+	 * We want all channel messages to be delivered on CPU 0.
+	 * This has been the behavior pre-win8. This is not
+	 * perf issue and having all channel messages delivered on CPU 0
+	 * would be ok.
+	 */
+	msg->target_vcpu = 0;
 
 	/*
 	 * Add to list before we send the request since we may

index 2a3420c..d4ab81b 100644
@@ -154,7 +154,7 @@ static int kvp_handle_handshake(struct hv_kvp_msg *msg)
 	pr_debug("KVP: userspace daemon ver. %d registered\n",
 		 KVP_OP_REGISTER);
 	kvp_register(dm_reg_value);
-	kvp_transaction.state = HVUTIL_READY;
+	hv_poll_channel(kvp_transaction.recv_channel, kvp_poll_wrapper);
 
 	return 0;
 }

index 81882d4..67def4a 100644
@@ -113,7 +113,7 @@ static int vss_handle_handshake(struct hv_vss_msg *vss_msg)
 	default:
 		return -EINVAL;
 	}
-	vss_transaction.state = HVUTIL_READY;
+	hv_poll_channel(vss_transaction.recv_channel, vss_poll_wrapper);
 	pr_debug("VSS: userspace daemon ver. %d registered\n", dm_reg_value);
 	return 0;
 }

index 96234b6..5d51d6f 100644
@@ -254,7 +254,7 @@ int main(int argc, char *argv[])
 			syslog(LOG_ERR, "Illegal op:%d\n", op);
 		}
 		vss_msg->error = error;
-		len = write(vss_fd, &error, sizeof(struct hv_vss_msg));
+		len = write(vss_fd, vss_msg, sizeof(struct hv_vss_msg));
 		if (len != sizeof(struct hv_vss_msg)) {
 			syslog(LOG_ERR, "write failed; error: %d %s", errno,
 			       strerror(errno));