patch "hv: acquire vmbus_connection.channel_mutex in vmbus_free_channels()" added to char-misc-next

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

hv: acquire vmbus_connection.channel_mutex in vmbus_free_channels()

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: Vitaly Kuznetsov <[email protected]>
Date: Sat, 3 Dec 2016 12:34:32 -0800
Subject: hv: acquire vmbus_connection.channel_mutex in vmbus_free_channels()

"kernel BUG at drivers/hv/channel_mgmt.c:350!" is observed when hv_vmbus module is unloaded. BUG_ON() was introduced in commit 85d9aa705184 ("Drivers: hv: vmbus: add an API vmbus_hvsock_device_unregister()") as vmbus_free_channels() codepath was apparently forgotten.

---
 drivers/hv/channel_mgmt.c | 2 ++
 1 file changed, 2 insertions(+)

index e5d1b0e6c922..26b419203f16 100644
@@ -389,6 +389,7 @@ void vmbus_free_channels(void)
 {
 	struct vmbus_channel *channel, *tmp;
 
+	mutex_lock(&vmbus_connection.channel_mutex);
 	list_for_each_entry_safe(channel, tmp, &vmbus_connection.chn_list,
 		listentry) {
 		/* hv_process_channel_removal() needs this */

@@ -396,6 +397,7 @@ void vmbus_free_channels(void)
 
 		vmbus_device_unregister(channel->device_obj);
 	}
+	mutex_unlock(&vmbus_connection.channel_mutex);
 }
 
 /*

2.10.2