Patch "Drivers: hv: util: Backup: Fix a rescind processing issue" 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

Drivers: hv: util: Backup: Fix a rescind processing issue

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:
drivers-hv-util-backup-fix-a-rescind-processing-issue.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: "K. Y. Srinivasan" <[email protected]>
Date: Thu, 22 Dec 2016 16:54:03 -0800
Subject: Drivers: hv: util: Backup: Fix a rescind processing issue

From: K. Y. Srinivasan <[email protected]>

commit d77044d142e960f7b5f814a91ecb8bcf86aa552c upstream.

VSS may use a char device to support the communication between the user level daemon and the driver. When the VSS channel is rescinded we need to make sure that the char device is fully cleaned up before we can process a new VSS offer from the host. Implement this logic.

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

@@ -66,6 +66,7 @@ static int dm_reg_value;
 static const char vss_devname[] = "vmbus/hv_vss";
 static __u8 *recv_buffer;
 static struct hvutil_transport *hvt;
+static struct completion release_event;
 
 static void vss_send_op(struct work_struct *dummy);
 static void vss_timeout_func(struct work_struct *dummy);

@@ -326,11 +327,13 @@ static void vss_on_reset(void)
 	if (cancel_delayed_work_sync(&vss_timeout_work))
 		vss_respond_to_host(HV_E_FAIL);
 	vss_transaction.state = HVUTIL_DEVICE_INIT;
+	complete(&release_event);
 }
 
 int
 hv_vss_init(struct hv_util_service *srv)
 {
+	init_completion(&release_event);
 	if (vmbus_proto_version < VERSION_WIN8_1) {
 		pr_warn("Integration service 'Backup (volume snapshot)'"
 			" not supported on this host version.\n");

@@ -360,4 +363,5 @@ void hv_vss_deinit(void)
 	cancel_delayed_work_sync(&vss_timeout_work);
 	cancel_work_sync(&vss_send_op_work);
 	hvutil_transport_destroy(hvt);
+	wait_for_completion(&release_event);
 }

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

queue-4.4/hv-init-percpu_list-in-hv_synic_alloc.patch queue-4.4/drivers-hv-util-backup-fix-a-rescind-processing-issue.patch queue-4.4/drivers-hv-util-fcopy-fix-a-rescind-processing-issue.patch queue-4.4/scsi-storvsc-use-tagged-srb-requests-if-supported-by-the-device.patch queue-4.4/drivers-hv-util-kvp-fix-a-rescind-processing-issue.patch queue-4.4/hv-allocate-synic-pages-for-all-present-cpus.patch queue-4.4/scsi-storvsc-properly-set-residual-data-length-on-errors.patch queue-4.4/scsi-storvsc-properly-handle-srb_error-when-sense-message-is-present.patch