patch "Drivers: hv: util: Backup: Fix a rescind processing issue" added to char-misc-next

[<gregkh@linuxfoundation.org>]

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 my char-misc git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-next branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will also be merged in the next major kernel release
during the merge window.

If you have any questions about this process, please let me know.


>From d77044d142e960f7b5f814a91ecb8bcf86aa552c Mon Sep 17 00:00:00 2001
From: "K. Y. Srinivasan" <kys@microsoft.com>
Date: Thu, 22 Dec 2016 16:54:03 -0800
Subject: Drivers: hv: util: Backup: Fix a rescind processing issue

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 When the VSS channel is rescinded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.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/hv/hv_snapshot.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/hv/hv_snapshot.c b/drivers/hv/hv_snapshot.c
index eee238cc60bd..4e543dbb731a 100644
--- a/drivers/hv/hv_snapshot.c
+++ b/drivers/hv/hv_snapshot.c
@@ -69,6 +69,7 @@ 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_timeout_func(struct work_struct *dummy);
 static void vss_handle_request(struct work_struct *dummy);
@@ -345,11 +346,13 @@ 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");
@@ -382,4 +385,5 @@ void hv_vss_deinit(void)
 	cancel_delayed_work_sync(&vss_timeout_work);
 	cancel_work_sync(&vss_handle_request_work);
 	hvutil_transport_destroy(hvt);
+	wait_for_completion(&release_event);
 }
-- 
2.11.0