3.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: "K. Y. Srinivasan" <[email protected]> commit 288fa3e022eb85fa151e0f9bcd15caeb81679af6 upstream. As part of updating the vmbus protocol, the function hv_need_to_signal() was introduced. This functions helps optimize signalling from guest to host. The newly added memory barrier is needed to ensure that we correctly decide when to signal the host. Signed-off-by: K. Y. Srinivasan <[email protected]> Reviewed-by: Haiyang Zhang <[email protected]> Reported-by: Olaf Hering <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/hv/ring_buffer.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/hv/ring_buffer.c +++ b/drivers/hv/ring_buffer.c @@ -71,6 +71,7 @@ u32 hv_end_read(struct hv_ring_buffer_in static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi) { + smp_mb(); if (rbi->ring_buffer->interrupt_mask) return false; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
