Merge pull request #83 from ijc25/hyperv-sockets

hyperv-socks: Backport patches.

alpine/kernel/kernel_config

@@ -1197,6 +1197,7 @@ CONFIG_OPENVSWITCH_VXLAN=y
 CONFIG_VSOCKETS=y
 CONFIG_VIRTIO_VSOCKETS=y
 CONFIG_VIRTIO_VSOCKETS_COMMON=y
+CONFIG_HYPERV_SOCK=y
 CONFIG_NETLINK_MMAP=y
 CONFIG_NETLINK_DIAG=y
 CONFIG_MPLS=y
@@ -1225,6 +1226,7 @@ CONFIG_NET_FLOW_LIMIT=y
 # CONFIG_IRDA is not set
 # CONFIG_BT is not set
 # CONFIG_AF_RXRPC is not set
+# CONFIG_AF_KCM is not set
 CONFIG_FIB_RULES=y
 # CONFIG_WIRELESS is not set
 # CONFIG_WIMAX is not set

alpine/kernel/patches/0001-virtio-make-find_vqs-checkpatch.pl-friendly.patch

@@ -1,7 +1,7 @@
 From d8f7730e3211cdb16cd9d26143121aeb05f22509 Mon Sep 17 00:00:00 2001
 From: Stefan Hajnoczi <stefanha@redhat.com>
 Date: Thu, 17 Dec 2015 16:53:43 +0800
-Subject: [PATCH 1/9] virtio: make find_vqs() checkpatch.pl-friendly
+Subject: [PATCH 01/25] virtio: make find_vqs() checkpatch.pl-friendly
 
 checkpatch.pl wants arrays of strings declared as follows:
 

alpine/kernel/patches/0002-VSOCK-constify-vmci_transport_notify_ops-structures.patch

@@ -1,7 +1,7 @@
 From 0260029492a1503e871236767ed86e2fc3862cc2 Mon Sep 17 00:00:00 2001
 From: Julia Lawall <julia.lawall@lip6.fr>
 Date: Sat, 21 Nov 2015 18:39:17 +0100
-Subject: [PATCH 2/9] VSOCK: constify vmci_transport_notify_ops structures
+Subject: [PATCH 02/25] VSOCK: constify vmci_transport_notify_ops structures
 
 The vmci_transport_notify_ops structures are never modified, so declare
 them as const.

alpine/kernel/patches/0003-AF_VSOCK-Shrink-the-area-influenced-by-prepare_to_wa.patch

@@ -1,7 +1,7 @@
 From 6a585c01a353551a69af45bf31606f13115480d1 Mon Sep 17 00:00:00 2001
 From: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
 Date: Tue, 22 Mar 2016 17:05:52 +0100
-Subject: [PATCH 3/9] AF_VSOCK: Shrink the area influenced by prepare_to_wait
+Subject: [PATCH 03/25] AF_VSOCK: Shrink the area influenced by prepare_to_wait
 
 When a thread is prepared for waiting by calling prepare_to_wait, sleeping
 is not allowed until either the wait has taken place or finish_wait has

alpine/kernel/patches/0004-VSOCK-transport-specific-vsock_transport-functions.patch

@@ -1,7 +1,7 @@
 From a3f136168f164f66de1de277a08b76f54b289d5a Mon Sep 17 00:00:00 2001
 From: Stefan Hajnoczi <stefanha@redhat.com>
 Date: Thu, 17 Dec 2015 11:10:21 +0800
-Subject: [PATCH 4/9] VSOCK: transport-specific vsock_transport functions
+Subject: [PATCH 04/25] VSOCK: transport-specific vsock_transport functions
 
 struct vsock_transport contains function pointers called by AF_VSOCK
 core code.  The transport may want its own transport-specific function

alpine/kernel/patches/0005-VSOCK-Introduce-virtio_vsock_common.ko.patch

@@ -1,7 +1,7 @@
 From 4018aa8a812fd6f1a64e3d227550bf5752127314 Mon Sep 17 00:00:00 2001
 From: Asias He <asias@redhat.com>
 Date: Thu, 13 Jun 2013 18:27:00 +0800
-Subject: [PATCH 5/9] VSOCK: Introduce virtio_vsock_common.ko
+Subject: [PATCH 05/25] VSOCK: Introduce virtio_vsock_common.ko
 
 This module contains the common code and header files for the following
 virtio_transporto and vhost_vsock kernel modules.

alpine/kernel/patches/0006-VSOCK-Introduce-virtio_transport.ko.patch

@@ -1,7 +1,7 @@
 From ccaac837ceb4a9582bb57f71e0cac791f7336b19 Mon Sep 17 00:00:00 2001
 From: Asias He <asias@redhat.com>
 Date: Thu, 13 Jun 2013 18:28:48 +0800
-Subject: [PATCH 6/9] VSOCK: Introduce virtio_transport.ko
+Subject: [PATCH 06/25] VSOCK: Introduce virtio_transport.ko
 
 VM sockets virtio transport implementation.  This driver runs in the
 guest.

alpine/kernel/patches/0007-VSOCK-Introduce-vhost_vsock.ko.patch

@@ -1,7 +1,7 @@
 From f52efbc874c742a671939ea6408c59545025007d Mon Sep 17 00:00:00 2001
 From: Asias He <asias@redhat.com>
 Date: Thu, 13 Jun 2013 18:29:21 +0800
-Subject: [PATCH 7/9] VSOCK: Introduce vhost_vsock.ko
+Subject: [PATCH 07/25] VSOCK: Introduce vhost_vsock.ko
 
 VM sockets vhost transport implementation.  This driver runs on the
 host.

alpine/kernel/patches/0008-VSOCK-Add-Makefile-and-Kconfig.patch

@@ -1,7 +1,7 @@
 From e8c8f5299fd202db5d56a10f1dc0a4e464e9a211 Mon Sep 17 00:00:00 2001
 From: Asias He <asias@redhat.com>
 Date: Thu, 13 Jun 2013 18:30:19 +0800
-Subject: [PATCH 8/9] VSOCK: Add Makefile and Kconfig
+Subject: [PATCH 08/25] VSOCK: Add Makefile and Kconfig
 
 Enable virtio-vsock and vhost-vsock.
 

alpine/kernel/patches/0009-VSOCK-Only-allow-host-network-namespace-to-use-AF_VS.patch

@@ -1,7 +1,8 @@
 From 550ec4c8f90f2bf99c1bcb13b2f8476780f42418 Mon Sep 17 00:00:00 2001
 From: Ian Campbell <ian.campbell@docker.com>
 Date: Mon, 4 Apr 2016 14:50:10 +0100
-Subject: [PATCH 9/9] VSOCK: Only allow host network namespace to use AF_VSOCK.
+Subject: [PATCH 09/25] VSOCK: Only allow host network namespace to use
+ AF_VSOCK.
 
 The VSOCK addressing schema does not really lend itself to simply creating an
 alternative end point address within a namespace.

alpine/kernel/patches/0010-Drivers-hv-vmbus-serialize-process_chn_event-and-vmb.patch

@@ -0,0 +1,87 @@
+From 1f7906c43fe139e15c19f35a4493a7ca61a6463f Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 14 Dec 2015 16:01:47 -0800
+Subject: [PATCH 10/25] Drivers: hv: vmbus: serialize process_chn_event() and
+ vmbus_close_internal()
+
+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.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 63d55b2aeb5e4faa170316fee73c3c47ea9268c7)
+---
+ drivers/hv/channel.c | 21 +++++++++++++++++++--
+ 1 file changed, 19 insertions(+), 2 deletions(-)
+
+diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
+index 9098f13..6a90c69 100644
+--- a/drivers/hv/channel.c
++++ b/drivers/hv/channel.c
+@@ -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;
+ }
+ 
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0011-Drivers-hv-vmbus-do-sanity-check-of-channel-state-in.patch

@@ -0,0 +1,42 @@
+From 00375a20748490730b2f004bfe44e83abecec5f1 Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 14 Dec 2015 16:01:48 -0800
+Subject: [PATCH 11/25] Drivers: hv: vmbus: do sanity check of channel state in
+ vmbus_close_internal()
+
+This fixes an incorrect assumption of channel state in the function.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 64b7faf903dae2df94d89edf2c688b16751800e4)
+---
+ drivers/hv/channel.c | 12 ++++++++++++
+ 1 file changed, 12 insertions(+)
+
+diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
+index 6a90c69..b3c14ca 100644
+--- a/drivers/hv/channel.c
++++ b/drivers/hv/channel.c
+@@ -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 */
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0012-Drivers-hv-vmbus-fix-rescind-offer-handling-for-devi.patch

@@ -0,0 +1,122 @@
+From 53cd041cabf572ec98d5b911abfff1a3baf1ccaa Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 14 Dec 2015 16:01:49 -0800
+Subject: [PATCH 12/25] Drivers: hv: vmbus: fix rescind-offer handling for
+ device without a driver
+
+In the path vmbus_onoffer_rescind() -> vmbus_device_unregister()  ->
+device_unregister() -> ... -> __device_release_driver(), we can see for a
+device without a driver loaded: dev->driver is NULL, so
+dev->bus->remove(dev), namely vmbus_remove(), isn't invoked.
+
+As a result, vmbus_remove() -> hv_process_channel_removal() isn't invoked
+and some cleanups(like sending a CHANNELMSG_RELID_RELEASED message to the
+host) aren't done.
+
+We can demo the issue this way:
+1. rmmod hv_utils;
+2. disable the Heartbeat Integration Service in Hyper-V Manager and lsvmbus
+shows the device disappears.
+3. re-enable the Heartbeat in Hyper-V Manager and modprobe hv_utils, but
+lsvmbus shows the device can't appear again.
+This is because, the host thinks the VM hasn't released the relid, so can't
+re-offer the device to the VM.
+
+We can fix the issue by moving hv_process_channel_removal()
+from vmbus_close_internal() to vmbus_device_release(), since the latter is
+always invoked on device_unregister(), whether or not the dev has a driver
+loaded.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 34c6801e3310ad286c7bb42bc88d42926b8f99bf)
+---
+ drivers/hv/channel.c      |  6 ------
+ drivers/hv/channel_mgmt.c |  6 +++---
+ drivers/hv/vmbus_drv.c    | 15 +++------------
+ 3 files changed, 6 insertions(+), 21 deletions(-)
+
+diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
+index b3c14ca..2889d97 100644
+--- a/drivers/hv/channel.c
++++ b/drivers/hv/channel.c
+@@ -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);
+ 
+diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
+index 652afd1..bd2e9f6 100644
+--- a/drivers/hv/channel_mgmt.c
++++ b/drivers/hv/channel_mgmt.c
+@@ -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);
+diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
+index f19b6f7..7e46a48 100644
+--- a/drivers/hv/vmbus_drv.c
++++ b/drivers/hv/vmbus_drv.c
+@@ -602,23 +602,11 @@ 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;
+@@ -653,7 +641,10 @@ 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);
+ 
+ }
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0013-Drivers-hv-vmbus-release-relid-on-error-in-vmbus_pro.patch

@@ -0,0 +1,74 @@
+From 613d19efd48c06602018c0e7c6b4bf8d191105cd Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 14 Dec 2015 16:01:50 -0800
+Subject: [PATCH 13/25] Drivers: hv: vmbus: release relid on error in
+ vmbus_process_offer()
+
+We want to simplify vmbus_onoffer_rescind() by not invoking
+hv_process_channel_removal(NULL, ...).
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit f52078cf5711ce47c113a58702b35c8ff5f212f5)
+---
+ drivers/hv/channel_mgmt.c | 21 +++++++++++++++------
+ 1 file changed, 15 insertions(+), 6 deletions(-)
+
+diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
+index bd2e9f6..df76a71 100644
+--- a/drivers/hv/channel_mgmt.c
++++ b/drivers/hv/channel_mgmt.c
+@@ -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);
+@@ -585,7 +590,11 @@ 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;
+ 	}
+ 
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0014-Drivers-hv-vmbus-channge-vmbus_connection.channel_lo.patch

@@ -0,0 +1,116 @@
+From b9a136e91171bea99a140195ccb4bbea2a65551d Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 14 Dec 2015 16:01:51 -0800
+Subject: [PATCH 14/25] Drivers: hv: vmbus: channge
+ vmbus_connection.channel_lock to mutex
+
+spinlock is unnecessary here.
+mutex is enough.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit d6f591e339d23f434efda11917da511870891472)
+---
+ drivers/hv/channel_mgmt.c | 12 ++++++------
+ drivers/hv/connection.c   |  7 +++----
+ drivers/hv/hyperv_vmbus.h |  2 +-
+ 3 files changed, 10 insertions(+), 11 deletions(-)
+
+diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
+index df76a71..bd4f084 100644
+--- a/drivers/hv/channel_mgmt.c
++++ b/drivers/hv/channel_mgmt.c
+@@ -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();
+diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
+index 4fc2e88..521f48e 100644
+--- a/drivers/hv/connection.c
++++ b/drivers/hv/connection.c
+@@ -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;
+ }
+diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
+index 3782636..d9937be 100644
+--- a/drivers/hv/hyperv_vmbus.h
++++ b/drivers/hv/hyperv_vmbus.h
+@@ -678,7 +678,7 @@ struct vmbus_connection {
+ 
+ 	/* List of channels */
+ 	struct list_head chn_list;
+-	spinlock_t channel_lock;
++	struct mutex channel_mutex;
+ 
+ 	struct workqueue_struct *work_queue;
+ };
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0015-Drivers-hv-vmbus-add-a-helper-function-to-set-a-chan.patch

@@ -0,0 +1,36 @@
+From 37e0f1616a680b0b209c3555812c0691dacd74e0 Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:37 -0800
+Subject: [PATCH 15/25] Drivers: hv: vmbus: add a helper function to set a
+ channel's pending send size
+
+This will be used by the coming net/hvsock driver.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 3c75354d043ad546148d6992e40033ecaefc5ea5)
+---
+ include/linux/hyperv.h | 6 ++++++
+ 1 file changed, 6 insertions(+)
+
+diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
+index ae6a711..fda6310 100644
+--- a/include/linux/hyperv.h
++++ b/include/linux/hyperv.h
+@@ -792,6 +792,12 @@ static inline void *get_per_channel_state(struct vmbus_channel *c)
+ 	return c->per_channel_state;
+ }
+ 
++static inline void set_channel_pending_send_size(struct vmbus_channel *c,
++						 u32 size)
++{
++	c->outbound.ring_buffer->pending_send_sz = size;
++}
++
+ void vmbus_onmessage(void *context);
+ 
+ int vmbus_request_offers(void);
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0016-Drivers-hv-vmbus-define-the-new-offer-type-for-Hyper.patch

@@ -0,0 +1,44 @@
+From 7d695c9e75755b005a7f45f99dfd7d3bb641e3a8 Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:38 -0800
+Subject: [PATCH 16/25] Drivers: hv: vmbus: define the new offer type for
+ Hyper-V socket (hvsock)
+
+A helper function is also added.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit e8d6ca023efce3bd80050dcd9e708ee3cf8babd4)
+---
+ include/linux/hyperv.h | 7 +++++++
+ 1 file changed, 7 insertions(+)
+
+diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
+index fda6310..9fb2130 100644
+--- a/include/linux/hyperv.h
++++ b/include/linux/hyperv.h
+@@ -237,6 +237,7 @@ struct vmbus_channel_offer {
+ #define VMBUS_CHANNEL_LOOPBACK_OFFER			0x100
+ #define VMBUS_CHANNEL_PARENT_OFFER			0x200
+ #define VMBUS_CHANNEL_REQUEST_MONITORED_NOTIFICATION	0x400
++#define VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER		0x2000
+ 
+ struct vmpacket_descriptor {
+ 	u16 type;
+@@ -771,6 +772,12 @@ struct vmbus_channel {
+ 	enum hv_signal_policy  signal_policy;
+ };
+ 
++static inline bool is_hvsock_channel(const struct vmbus_channel *c)
++{
++	return !!(c->offermsg.offer.chn_flags &
++		  VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER);
++}
++
+ static inline void set_channel_signal_state(struct vmbus_channel *c,
+ 					    enum hv_signal_policy policy)
+ {
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0017-Drivers-hv-vmbus-vmbus_sendpacket_ctl-hvsock-avoid-u.patch

@@ -0,0 +1,45 @@
+From 8507cfd5b7af092d5cc5e99ff9852b3bc46c48c0 Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:39 -0800
+Subject: [PATCH 17/25] Drivers: hv: vmbus: vmbus_sendpacket_ctl: hvsock: avoid
+ unnecessary signaling
+
+When the hvsock channel's outbound ringbuffer is full (i.e.,
+hv_ringbuffer_write() returns -EAGAIN), we should avoid the unnecessary
+signaling the host.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 5f363bc38f810d238d1e8b19998625ddec3b8138)
+---
+ drivers/hv/channel.c | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
+index 2889d97..a7f9e3e 100644
+--- a/drivers/hv/channel.c
++++ b/drivers/hv/channel.c
+@@ -659,6 +659,9 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
+ 	 * 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.
++	 * NOTE: in this case, the hvsock channel is an exception, because
++	 * it looks the host side's hvsock implementation has a throttling
++	 * mechanism which can hurt the performance otherwise.
+ 	 */
+ 
+ 	if (channel->signal_policy)
+@@ -666,7 +669,8 @@ int vmbus_sendpacket_ctl(struct vmbus_channel *channel, void *buffer,
+ 	else
+ 		kick_q = true;
+ 
+-	if (((ret == 0) && kick_q && signal) || (ret))
++	if (((ret == 0) && kick_q && signal) ||
++	    (ret && !is_hvsock_channel(channel)))
+ 		vmbus_setevent(channel);
+ 
+ 	return ret;
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0018-Drivers-hv-vmbus-define-a-new-VMBus-message-type-for.patch

@@ -0,0 +1,101 @@
+From 746cdb5f4c824ef3af9d12909818a077a0cf303c Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:40 -0800
+Subject: [PATCH 18/25] Drivers: hv: vmbus: define a new VMBus message type for
+ hvsock
+
+A function to send the type of message is also added.
+
+The coming net/hvsock driver will use this function to proactively request
+the host to offer a VMBus channel for a new hvsock connection.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 5c23a1a5c60b0f472cfa61cd7d8279f8aaeb5b64)
+---
+ drivers/hv/channel.c      | 15 +++++++++++++++
+ drivers/hv/channel_mgmt.c |  4 ++++
+ include/linux/hyperv.h    | 13 +++++++++++++
+ 3 files changed, 32 insertions(+)
+
+diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
+index a7f9e3e..239b072 100644
+--- a/drivers/hv/channel.c
++++ b/drivers/hv/channel.c
+@@ -219,6 +219,21 @@ error0:
+ }
+ EXPORT_SYMBOL_GPL(vmbus_open);
+ 
++/* Used for Hyper-V Socket: a guest client's connect() to the host */
++int vmbus_send_tl_connect_request(const uuid_le *shv_guest_servie_id,
++				  const uuid_le *shv_host_servie_id)
++{
++	struct vmbus_channel_tl_connect_request conn_msg;
++
++	memset(&conn_msg, 0, sizeof(conn_msg));
++	conn_msg.header.msgtype = CHANNELMSG_TL_CONNECT_REQUEST;
++	conn_msg.guest_endpoint_id = *shv_guest_servie_id;
++	conn_msg.host_service_id = *shv_host_servie_id;
++
++	return vmbus_post_msg(&conn_msg, sizeof(conn_msg));
++}
++EXPORT_SYMBOL_GPL(vmbus_send_tl_connect_request);
++
+ /*
+  * create_gpadl_header - Creates a gpadl for the specified buffer
+  */
+diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
+index bd4f084..4d61f41 100644
+--- a/drivers/hv/channel_mgmt.c
++++ b/drivers/hv/channel_mgmt.c
+@@ -820,6 +820,10 @@ struct vmbus_channel_message_table_entry
+ 	{CHANNELMSG_VERSION_RESPONSE,		1, vmbus_onversion_response},
+ 	{CHANNELMSG_UNLOAD,			0, NULL},
+ 	{CHANNELMSG_UNLOAD_RESPONSE,		1, vmbus_unload_response},
++	{CHANNELMSG_18,				0, NULL},
++	{CHANNELMSG_19,				0, NULL},
++	{CHANNELMSG_20,				0, NULL},
++	{CHANNELMSG_TL_CONNECT_REQUEST,		0, NULL},
+ };
+ 
+ /*
+diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
+index 9fb2130..3f485a4 100644
+--- a/include/linux/hyperv.h
++++ b/include/linux/hyperv.h
+@@ -394,6 +394,10 @@ enum vmbus_channel_message_type {
+ 	CHANNELMSG_VERSION_RESPONSE		= 15,
+ 	CHANNELMSG_UNLOAD			= 16,
+ 	CHANNELMSG_UNLOAD_RESPONSE		= 17,
++	CHANNELMSG_18				= 18,
++	CHANNELMSG_19				= 19,
++	CHANNELMSG_20				= 20,
++	CHANNELMSG_TL_CONNECT_REQUEST		= 21,
+ 	CHANNELMSG_COUNT
+ };
+ 
+@@ -564,6 +568,13 @@ struct vmbus_channel_initiate_contact {
+ 	u64 monitor_page2;
+ } __packed;
+ 
++/* Hyper-V socket: guest's connect()-ing to host */
++struct vmbus_channel_tl_connect_request {
++	struct vmbus_channel_message_header header;
++	uuid_le guest_endpoint_id;
++	uuid_le host_service_id;
++} __packed;
++
+ struct vmbus_channel_version_response {
+ 	struct vmbus_channel_message_header header;
+ 	u8 version_supported;
+@@ -1276,4 +1287,6 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid);
+ 
+ extern __u32 vmbus_proto_version;
+ 
++int vmbus_send_tl_connect_request(const uuid_le *shv_guest_servie_id,
++				  const uuid_le *shv_host_servie_id);
+ #endif /* _HYPERV_H */
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0019-Drivers-hv-vmbus-add-a-hvsock-flag-in-struct-hv_driv.patch

@@ -0,0 +1,64 @@
+From fb6b14a429dae008b7fee772a1e27cb09db459b7 Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:41 -0800
+Subject: [PATCH 19/25] Drivers: hv: vmbus: add a hvsock flag in struct
+ hv_driver
+
+Only the coming hv_sock driver has a "true" value for this flag.
+
+We treat the hvsock offers/channels as special VMBus devices.
+Since the hv_sock driver handles all the hvsock offers/channels, we need to
+tweak vmbus_match() for hv_sock driver, so we introduce this flag.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 8981da320a11217589aa3c50f9e891bcdef07ece)
+---
+ drivers/hv/vmbus_drv.c |  4 ++++
+ include/linux/hyperv.h | 14 ++++++++++++++
+ 2 files changed, 18 insertions(+)
+
+diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
+index 7e46a48..7d607ad 100644
+--- a/drivers/hv/vmbus_drv.c
++++ b/drivers/hv/vmbus_drv.c
+@@ -563,6 +563,10 @@ 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);
+ 
++	/* The hv_sock driver handles all hv_sock offers. */
++	if (is_hvsock_channel(hv_dev->channel))
++		return drv->hvsock;
++
+ 	if (hv_vmbus_get_id(drv->id_table, hv_dev->dev_type.b))
+ 		return 1;
+ 
+diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
+index 3f485a4..9ee79af 100644
+--- a/include/linux/hyperv.h
++++ b/include/linux/hyperv.h
+@@ -966,6 +966,20 @@ extern void vmbus_ontimer(unsigned long data);
+ struct hv_driver {
+ 	const char *name;
+ 
++	/*
++	 * A hvsock offer, which has a VMBUS_CHANNEL_TLNPI_PROVIDER_OFFER
++	 * channel flag, actually doesn't mean a synthetic device because the
++	 * offer's if_type/if_instance can change for every new hvsock
++	 * connection.
++	 *
++	 * However, to facilitate the notification of new-offer/rescind-offer
++	 * from vmbus driver to hvsock driver, we can handle hvsock offer as
++	 * a special vmbus device, and hence we need the below flag to
++	 * indicate if the driver is the hvsock driver or not: we need to
++	 * specially treat the hvosck offer & driver in vmbus_match().
++	 */
++	bool hvsock;
++
+ 	/* the device type supported by this driver */
+ 	uuid_le dev_type;
+ 	const struct hv_vmbus_device_id *id_table;
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0020-Drivers-hv-vmbus-add-a-per-channel-rescind-callback.patch

@@ -0,0 +1,72 @@
+From 4a2d55757c137c2e574500227cb2efe77a26ee3a Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:42 -0800
+Subject: [PATCH 20/25] Drivers: hv: vmbus: add a per-channel rescind callback
+
+This will be used by the coming hv_sock driver.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 499e8401a515d04daa986b995da710d2b9737764)
+---
+ drivers/hv/channel_mgmt.c | 11 +++++++++++
+ include/linux/hyperv.h    |  9 +++++++++
+ 2 files changed, 20 insertions(+)
+
+diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
+index 4d61f41..421e3dd 100644
+--- a/drivers/hv/channel_mgmt.c
++++ b/drivers/hv/channel_mgmt.c
+@@ -603,6 +603,10 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+ 	spin_unlock_irqrestore(&channel->lock, flags);
+ 
+ 	if (channel->device_obj) {
++		if (channel->chn_rescind_callback) {
++			channel->chn_rescind_callback(channel);
++			return;
++		}
+ 		/*
+ 		 * We will have to unregister this device from the
+ 		 * driver core.
+@@ -972,3 +976,10 @@ bool vmbus_are_subchannels_present(struct vmbus_channel *primary)
+ 	return ret;
+ }
+ EXPORT_SYMBOL_GPL(vmbus_are_subchannels_present);
++
++void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
++		void (*chn_rescind_cb)(struct vmbus_channel *))
++{
++	channel->chn_rescind_callback = chn_rescind_cb;
++}
++EXPORT_SYMBOL_GPL(vmbus_set_chn_rescind_callback);
+diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
+index 9ee79af..09e9ec1 100644
+--- a/include/linux/hyperv.h
++++ b/include/linux/hyperv.h
+@@ -742,6 +742,12 @@ struct vmbus_channel {
+ 	void (*sc_creation_callback)(struct vmbus_channel *new_sc);
+ 
+ 	/*
++	 * Channel rescind callback. Some channels (the hvsock ones), need to
++	 * register a callback which is invoked in vmbus_onoffer_rescind().
++	 */
++	void (*chn_rescind_callback)(struct vmbus_channel *channel);
++
++	/*
+ 	 * The spinlock to protect the structure. It is being used to protect
+ 	 * test-and-set access to various attributes of the structure as well
+ 	 * as all sc_list operations.
+@@ -827,6 +833,9 @@ int vmbus_request_offers(void);
+ void vmbus_set_sc_create_callback(struct vmbus_channel *primary_channel,
+ 			void (*sc_cr_cb)(struct vmbus_channel *new_sc));
+ 
++void vmbus_set_chn_rescind_callback(struct vmbus_channel *channel,
++		void (*chn_rescind_cb)(struct vmbus_channel *));
++
+ /*
+  * Retrieve the (sub) channel on which to send an outgoing request.
+  * When a primary channel has multiple sub-channels, we choose a
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0021-Drivers-hv-vmbus-add-an-API-vmbus_hvsock_device_unre.patch

@@ -0,0 +1,153 @@
+From b6c9f23164d3e7460d8983d27f2df194ab5e9a0b Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Wed, 27 Jan 2016 22:29:43 -0800
+Subject: [PATCH 21/25] Drivers: hv: vmbus: add an API
+ vmbus_hvsock_device_unregister()
+
+The hvsock driver needs this API to release all the resources related
+to the channel.
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+(cherry picked from commit 85d9aa705184a4504d0330017e3956fcdae8a9d6)
+---
+ drivers/hv/channel_mgmt.c | 33 ++++++++++++++++++++++++++++-----
+ drivers/hv/connection.c   |  4 ++--
+ include/linux/hyperv.h    |  2 ++
+ 3 files changed, 32 insertions(+), 7 deletions(-)
+
+diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c
+index 421e3dd..0fe9665 100644
+--- a/drivers/hv/channel_mgmt.c
++++ b/drivers/hv/channel_mgmt.c
+@@ -195,6 +195,7 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+ 	vmbus_release_relid(relid);
+ 
+ 	BUG_ON(!channel->rescind);
++	BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
+ 
+ 	if (channel->target_cpu != get_cpu()) {
+ 		put_cpu();
+@@ -206,9 +207,7 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid)
+ 	}
+ 
+ 	if (channel->primary_channel == NULL) {
+-		mutex_lock(&vmbus_connection.channel_mutex);
+ 		list_del(&channel->listentry);
+-		mutex_unlock(&vmbus_connection.channel_mutex);
+ 
+ 		primary_channel = channel;
+ 	} else {
+@@ -251,6 +250,7 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
+ 	struct vmbus_channel *channel;
+ 	bool fnew = true;
+ 	unsigned long flags;
++	int ret;
+ 
+ 	/* Make sure this is a new offer */
+ 	mutex_lock(&vmbus_connection.channel_mutex);
+@@ -330,7 +330,11 @@ static void vmbus_process_offer(struct vmbus_channel *newchannel)
+ 	 * binding which eventually invokes the device driver's AddDevice()
+ 	 * method.
+ 	 */
+-	if (vmbus_device_register(newchannel->device_obj) != 0) {
++	mutex_lock(&vmbus_connection.channel_mutex);
++	ret = vmbus_device_register(newchannel->device_obj);
++	mutex_unlock(&vmbus_connection.channel_mutex);
++
++	if (ret != 0) {
+ 		pr_err("unable to add child device object (relid %d)\n",
+ 			newchannel->offermsg.child_relid);
+ 		kfree(newchannel->device_obj);
+@@ -587,6 +591,8 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+ 	struct device *dev;
+ 
+ 	rescind = (struct vmbus_channel_rescind_offer *)hdr;
++
++	mutex_lock(&vmbus_connection.channel_mutex);
+ 	channel = relid2channel(rescind->child_relid);
+ 
+ 	if (channel == NULL) {
+@@ -595,7 +601,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+ 		 * vmbus_process_offer(), we have already invoked
+ 		 * vmbus_release_relid() on error.
+ 		 */
+-		return;
++		goto out;
+ 	}
+ 
+ 	spin_lock_irqsave(&channel->lock, flags);
+@@ -605,7 +611,7 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+ 	if (channel->device_obj) {
+ 		if (channel->chn_rescind_callback) {
+ 			channel->chn_rescind_callback(channel);
+-			return;
++			goto out;
+ 		}
+ 		/*
+ 		 * We will have to unregister this device from the
+@@ -620,8 +626,25 @@ static void vmbus_onoffer_rescind(struct vmbus_channel_message_header *hdr)
+ 		hv_process_channel_removal(channel,
+ 			channel->offermsg.child_relid);
+ 	}
++
++out:
++	mutex_unlock(&vmbus_connection.channel_mutex);
+ }
+ 
++void vmbus_hvsock_device_unregister(struct vmbus_channel *channel)
++{
++	mutex_lock(&vmbus_connection.channel_mutex);
++
++	BUG_ON(!is_hvsock_channel(channel));
++
++	channel->rescind = true;
++	vmbus_device_unregister(channel->device_obj);
++
++	mutex_unlock(&vmbus_connection.channel_mutex);
++}
++EXPORT_SYMBOL_GPL(vmbus_hvsock_device_unregister);
++
++
+ /*
+  * vmbus_onoffers_delivered -
+  * This is invoked when all offers have been delivered.
+diff --git a/drivers/hv/connection.c b/drivers/hv/connection.c
+index 521f48e..09c08b5 100644
+--- a/drivers/hv/connection.c
++++ b/drivers/hv/connection.c
+@@ -285,7 +285,8 @@ struct vmbus_channel *relid2channel(u32 relid)
+ 	struct list_head *cur, *tmp;
+ 	struct vmbus_channel *cur_sc;
+ 
+-	mutex_lock(&vmbus_connection.channel_mutex);
++	BUG_ON(!mutex_is_locked(&vmbus_connection.channel_mutex));
++
+ 	list_for_each_entry(channel, &vmbus_connection.chn_list, listentry) {
+ 		if (channel->offermsg.child_relid == relid) {
+ 			found_channel = channel;
+@@ -304,7 +305,6 @@ struct vmbus_channel *relid2channel(u32 relid)
+ 			}
+ 		}
+ 	}
+-	mutex_unlock(&vmbus_connection.channel_mutex);
+ 
+ 	return found_channel;
+ }
+diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
+index 09e9ec1..af7ee0a 100644
+--- a/include/linux/hyperv.h
++++ b/include/linux/hyperv.h
+@@ -1043,6 +1043,8 @@ int __must_check __vmbus_driver_register(struct hv_driver *hv_driver,
+ 					 const char *mod_name);
+ void vmbus_driver_unregister(struct hv_driver *hv_driver);
+ 
++void vmbus_hvsock_device_unregister(struct vmbus_channel *channel);
++
+ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
+ 			resource_size_t min, resource_size_t max,
+ 			resource_size_t size, resource_size_t align,
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0023-net-add-the-AF_KCM-entries-to-family-name-tables.patch

@@ -0,0 +1,52 @@
+From 4e7679280dd0ad8e28f9ebeea70127ed4385222a Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 21 Mar 2016 02:51:09 -0700
+Subject: [PATCH 23/25] net: add the AF_KCM entries to family name tables
+
+This is for the recent kcm driver, which introduces AF_KCM(41) in
+b7ac4eb(kcm: Kernel Connection Multiplexor module).
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Cc: Signed-off-by: Tom Herbert <tom@herbertland.com>
+Origin: https://patchwork.ozlabs.org/patch/600006
+---
+ net/core/sock.c | 9 ++++++---
+ 1 file changed, 6 insertions(+), 3 deletions(-)
+
+diff --git a/net/core/sock.c b/net/core/sock.c
+index 0d91f7d..925def4 100644
+--- a/net/core/sock.c
++++ b/net/core/sock.c
+@@ -263,7 +263,8 @@ static const char *const af_family_key_strings[AF_MAX+1] = {
+   "sk_lock-AF_TIPC"  , "sk_lock-AF_BLUETOOTH", "sk_lock-IUCV"        ,
+   "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
+   "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
+-  "sk_lock-AF_NFC"   , "sk_lock-AF_VSOCK"    , "sk_lock-AF_MAX"
++  "sk_lock-AF_NFC"   , "sk_lock-AF_VSOCK"    , "sk_lock-AF_KCM"      ,
++  "sk_lock-AF_MAX"
+ };
+ static const char *const af_family_slock_key_strings[AF_MAX+1] = {
+   "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
+@@ -279,7 +280,8 @@ static const char *const af_family_slock_key_strings[AF_MAX+1] = {
+   "slock-AF_TIPC"  , "slock-AF_BLUETOOTH", "slock-AF_IUCV"     ,
+   "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
+   "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
+-  "slock-AF_NFC"   , "slock-AF_VSOCK"    ,"slock-AF_MAX"
++  "slock-AF_NFC"   , "slock-AF_VSOCK"    ,"slock-AF_KCM"       ,
++  "slock-AF_MAX"
+ };
+ static const char *const af_family_clock_key_strings[AF_MAX+1] = {
+   "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
+@@ -295,7 +297,8 @@ static const char *const af_family_clock_key_strings[AF_MAX+1] = {
+   "clock-AF_TIPC"  , "clock-AF_BLUETOOTH", "clock-AF_IUCV"     ,
+   "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
+   "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
+-  "clock-AF_NFC"   , "clock-AF_VSOCK"    , "clock-AF_MAX"
++  "clock-AF_NFC"   , "clock-AF_VSOCK"    , "clock-AF_KCM"      ,
++  "clock-AF_MAX"
+ };
+ 
+ /*
+-- 
+2.8.0.rc3
+

alpine/kernel/patches/0025-net-add-the-AF_HYPERV-entries-to-family-name-tables.patch

@@ -0,0 +1,49 @@
+From 0198717a05de80bc7769ed1d2c3a0cdf3c40fd7c Mon Sep 17 00:00:00 2001
+From: Dexuan Cui <decui@microsoft.com>
+Date: Mon, 21 Mar 2016 02:53:08 -0700
+Subject: [PATCH 25/25] net: add the AF_HYPERV entries to family name tables
+
+This is for the hv_sock driver, which introduces AF_HYPERV(42).
+
+Signed-off-by: Dexuan Cui <decui@microsoft.com>
+Cc: "K. Y. Srinivasan" <kys@microsoft.com>
+Cc: Haiyang Zhang <haiyangz@microsoft.com>
+Origin: https://patchwork.ozlabs.org/patch/600009
+---
+ net/core/sock.c | 6 +++---
+ 1 file changed, 3 insertions(+), 3 deletions(-)
+
+diff --git a/net/core/sock.c b/net/core/sock.c
+index 925def4..323f7a3 100644
+--- a/net/core/sock.c
++++ b/net/core/sock.c
+@@ -264,7 +264,7 @@ static const char *const af_family_key_strings[AF_MAX+1] = {
+   "sk_lock-AF_RXRPC" , "sk_lock-AF_ISDN"     , "sk_lock-AF_PHONET"   ,
+   "sk_lock-AF_IEEE802154", "sk_lock-AF_CAIF" , "sk_lock-AF_ALG"      ,
+   "sk_lock-AF_NFC"   , "sk_lock-AF_VSOCK"    , "sk_lock-AF_KCM"      ,
+-  "sk_lock-AF_MAX"
++  "sk_lock-AF_HYPERV", "sk_lock-AF_MAX"
+ };
+ static const char *const af_family_slock_key_strings[AF_MAX+1] = {
+   "slock-AF_UNSPEC", "slock-AF_UNIX"     , "slock-AF_INET"     ,
+@@ -281,7 +281,7 @@ static const char *const af_family_slock_key_strings[AF_MAX+1] = {
+   "slock-AF_RXRPC" , "slock-AF_ISDN"     , "slock-AF_PHONET"   ,
+   "slock-AF_IEEE802154", "slock-AF_CAIF" , "slock-AF_ALG"      ,
+   "slock-AF_NFC"   , "slock-AF_VSOCK"    ,"slock-AF_KCM"       ,
+-  "slock-AF_MAX"
++  "slock-AF_HYPERV", "slock-AF_MAX"
+ };
+ static const char *const af_family_clock_key_strings[AF_MAX+1] = {
+   "clock-AF_UNSPEC", "clock-AF_UNIX"     , "clock-AF_INET"     ,
+@@ -298,7 +298,7 @@ static const char *const af_family_clock_key_strings[AF_MAX+1] = {
+   "clock-AF_RXRPC" , "clock-AF_ISDN"     , "clock-AF_PHONET"   ,
+   "clock-AF_IEEE802154", "clock-AF_CAIF" , "clock-AF_ALG"      ,
+   "clock-AF_NFC"   , "clock-AF_VSOCK"    , "clock-AF_KCM"      ,
+-  "clock-AF_MAX"
++  "clock-AF_HYPERV", "clock-AF_MAX"
+ };
+ 
+ /*
+-- 
+2.8.0.rc3
+