Hi, On 09/30/2017 05:22 PM, Cong Wang wrote: > On Fri, Sep 29, 2017 at 5:26 PM, Vinicius Costa Gomes > <vinicius.go...@intel.com> wrote: >> From: Jesus Sanchez-Palencia <jesus.sanchez-palen...@intel.com> >> >> In qdisc_alloc() the dev_queue pointer was used without any checks being >> performed. If qdisc_create() gets a null dev_queue pointer, it just >> passes it along to qdisc_alloc(), leading to a crash. That happens if a >> root qdisc implements select_queue() and returns a null dev_queue >> pointer for an "invalid handle", for example. > > Does it make sense to let mqprio_select_queue() always return > non-NULL? > > At least mq_select_queue() returns queue #0 as a fallback.
I had seen that, but my understanding was that for mqprio the inner qdiscs are always related to one of the Tx netdev_queue per design. Returning any other queue as a fallback seemed like going against that to me. I'd rather keep this function as the patch is proposing, thus either returning the correct netdev_queue for a given handle, or NULL as a way to flag that something was 'wrong' with it. Returning queue #0 is misleading in that sense, imo. What do you think? Regards, Jesus
