Patch "[PATCH 038/135] drivers/hv: cleanup synic msrs if vmbus connect" has been added to the 4.4-stable tree

This is a note to let you know that I've just added the patch titled

[PATCH 038/135] drivers/hv: cleanup synic msrs if vmbus connect

to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
0038-drivers-hv-cleanup-synic-msrs-if-vmbus-connect-faile.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Andrey Smetanin <[email protected]>
Date: Mon, 14 Dec 2015 16:01:38 -0800
Subject: [PATCH 038/135] drivers/hv: cleanup synic msrs if vmbus connect
failed

[ Upstream commit 17efbee8ba02ef00d3b270998978f8a1a90f1d92 ]

Before vmbus_connect() synic is setup per vcpu - this means hypervisor receives writes at synic msr's and probably allocate hypervisor resources per synic setup.

If vmbus_connect() failed for some reason it's neccessary to cleanup synic setup by call hv_synic_cleanup() at each vcpu to get a chance to free allocated resources by hypervisor per synic.

This patch does appropriate cleanup in case of vmbus_connect() failure.

---
 drivers/hv/vmbus_drv.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

@@ -870,7 +870,7 @@ 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();

@@ -888,6 +888,8 @@ 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();

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/0038-drivers-hv-cleanup-synic-msrs-if-vmbus-connect-faile.patch