Opened 5 years ago

Last modified 5 years ago

#13360 reopened defect

Cannot compile 3.8.7 kernel is QoS and/or fair queueing (NET_SCHED) is disabled

Reported by: js@… Owned by: nbd
Priority: normal Milestone: Chaos Calmer 15.05
Component: kernel Version: Trunk
Keywords: Cc:


Since changeset 36304 kernel compilations fails if NET_SCHED is disabled with this error:

net/built-in.o: In function `dev_activate':
sysctl_net.c:(.text.dev_activate+0x19c): undefined reference to `fq_codel_qdisc_ops'
net/built-in.o: In function `mq_init':
sysctl_net.c:(.text.mq_init+0xec): undefined reference to `fq_codel_qdisc_ops'
make[4]: *** [vmlinux] Error 1

Attachments (0)

Change History (6)

comment:1 Changed 5 years ago by nbd

  • Owner changed from developers to nbd
  • Status changed from new to accepted

comment:2 Changed 5 years ago by anonymous

Removing these patches solves the issue:


comment:3 Changed 5 years ago by nbd

I will not remove those patches. I will probably force NET_SCHED to on, since fq_codel absolutely needs them. The switch to fq_codel was done for a reason, because pfifo_fast has really bad behavior when queues fill up.

comment:4 Changed 5 years ago by nbd

  • Resolution set to fixed
  • Status changed from accepted to closed

comment:5 Changed 5 years ago by js@…

  • Resolution fixed deleted
  • Status changed from closed to reopened

What if user wants to disable NET_SCHED to save some space? I'm not suggesting to remove these patches, what about adding checks if NET_SCH_FQ_CODEL is defined? If it is not then use pfifo_fast. The thing is that sch_generic.c and sch_mq.c are compiled even when NET_SCHED is disabled which leads the undefined reference error.

comment:6 Changed 5 years ago by anonymous

Benchmark fq_codel vs anything else. Then decide if you want to save a few hundred bytes of space.

sch_mq is integral to wifi.

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