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charset="us-ascii" On Wed, 11 Nov 2026 00:45:58 +0800, Yongjian Wang wrote: > Packetization layer path MTU discovery (net.ipv4.tcp_mtu_probing=2) has > no selftest coverage. > > Add a test for an active connection. Check that it starts at > tcp_base_mss, that it sends the first probe half way between > tcp_base_mss and the peer's MSS once cwnd allows it, and that an > acknowledged probe raises the MSS and leads to a larger probe. > > The SYN offers timestamps and the scripted SYN-ACK declines them. > This also checks that MTU probing uses the negotiated header length > for the initial send MSS. > > Signed-off-by: Yongjian Wang Reviewed-by: Kuniyuki Iwashima Thanks