On Thu, Mar 11, 2021 at 4:10 PM Jakub Kicinski <kuba@xxxxxxxxxx> wrote: > > And the "noqueue" queue is there because it's on top of hdlc_fr.c > somehow or some out of tree driver? Or do you install it manually? No, this driver is not related to "hdlc_fr.c" or any out-of-tree driver. The default qdisc is "noqueue" for this driver because this driver doesn't set "tx_queue_len". This means the value of "tx_queue_len" would be 0. In this case, "alloc_netdev_mqs" will automatically add the "IFF_NO_QUEUE" flag to the device, then "attach_one_default_qdisc" in "net/sched/sch_generic.c" will attach the "noqueue" qdisc for devices with the "IFF_NO_QUEUE" flag.
