1 files changed, 4 insertions, 0 deletions

diff --git a/net/ipv4/tcp_cubic.c b/net/ipv4/tcp_cubic.c
index f4fb2d4b90ad..5e0491d742ca 100644
--- a/net/ipv4/tcp_cubic.c
+++ b/net/ipv4/tcp_cubic.c
@@ -459,6 +459,10 @@ static int __init cubictcp_register(void)
         /* divide by bic_scale and by constant Srtt (100ms) */
         do_div(cube_factor, bic_scale * 10);
 
+        /* hystart needs ms clock resolution */
+        if (hystart && HZ < 1000)
+                cubictcp.flags |= TCP_CONG_RTT_STAMP;
+
         return tcp_register_congestion_control(&cubictcp);
 }