drivers: hv: check interrupt mask before read_index

[mirror_ubuntu-bionic-kernel.git] / drivers / hv / ring_buffer.c

diff --git a/drivers/hv/ring_buffer.c b/drivers/hv/ring_buffer.c
index 791f45dfc85dd9abc1847059650f7b6467001a0e..26c93cf9f6be4a083f47615318699e3110d39983 100644 (file)
--- a/drivers/hv/ring_buffer.c
+++ b/drivers/hv/ring_buffer.c
@@ -75,6 +75,8 @@ static bool hv_need_to_signal(u32 old_write, struct hv_ring_buffer_info *rbi)
        if (rbi->ring_buffer->interrupt_mask)
                return false;
 
+       /* check interrupt_mask before read_index */
+       rmb();
        /*
         * This is the only case we need to signal when the
         * ring transitions from being empty to non-empty.