Without the patch, vmbus_hvsock_device_unregister() can destroy the device prematurely when close() is called, and can cause NULl dereferencing or potential data loss (the last portion of the data stream may be dropped prematurely).
Signed-off-by: Dexuan Cui <de...@microsoft.com> Cc: K. Y. Srinivasan <k...@microsoft.com> Cc: Haiyang Zhang <haiya...@microsoft.com> Cc: Stephen Hemminger <sthem...@microsoft.com> --- The patch is rebased on today's char-misc tree's char-misc-linus branch. Please consider it for v4.14. drivers/hv/channel_mgmt.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 018d2e0..379b0df 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -937,7 +937,10 @@ void vmbus_hvsock_device_unregister(struct vmbus_channel *channel) { BUG_ON(!is_hvsock_channel(channel)); - channel->rescind = true; + /* We always get a rescind msg when a connection is closed. */ + while (!READ_ONCE(channel->probe_done) || !READ_ONCE(channel->rescind)) + msleep(1); + vmbus_device_unregister(channel->device_obj); } EXPORT_SYMBOL_GPL(vmbus_hvsock_device_unregister); -- 2.7.4 _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel