Drivers: hv: vmbus: Fix a bug in vmbus_establish_gpadl()

Correctly compute the local (gpadl) handle.
I would like to thank Michael Brown <mcb30@ipxe.org> for seeing this bug.

Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Reported-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index 433f72a1c0062be9b13dff78b6885d37a80a8738..c76ffbe59f65539597f5ba0cb5b50265ef2f3b7d 100644 (file)
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -366,8 +366,8 @@ int vmbus_establish_gpadl(struct vmbus_channel *channel, void *kbuffer,
        unsigned long flags;
        int ret = 0;
 
-       next_gpadl_handle = atomic_read(&vmbus_connection.next_gpadl_handle);
-       atomic_inc(&vmbus_connection.next_gpadl_handle);
+       next_gpadl_handle =
+               (atomic_inc_return(&vmbus_connection.next_gpadl_handle) - 1);
 
        ret = create_gpadl_header(kbuffer, size, &msginfo, &msgcount);
        if (ret)