[  385.305342] PPP generic driver version 2.4.2
[  385.306123] NET: Registered PF_PPPOX protocol family
[  385.309528] l2tp_core: L2TP core driver, V2.0
[  385.310576] l2tp_ppp: PPPoL2TP kernel driver, V2.0
[  392.695302] iperf3 (9689) used greatest stack depth: 11568 bytes left
[  392.735861] ppp0: recursion detected
[  392.931009] ppp0: recursion detected
[  393.139021] ppp0: recursion detected
[  393.555037] ppp0: recursion detected
[  393.760749] ppp0: recursion detected