[Make-wifi-fast] fq_codel_fast crash/lockup

[Sebastian Gottschall]

if you mind.

running on arm kernel htb+fq_codel_fast

INFO: rcu_preempt self-detected stall on CPU
         0-...: (1 GPs behind) idle=0ab/140000000000001/0 
softirq=2280/2285 fqs=5984
          (t=6000 jiffies g=211 c=210 q=565)
Task dump for CPU 0:
tc              R running      0  1024    890 0x00000002
Backtrace:
[<8001b71c>] (dump_backtrace) from [<8001b9c0>] (show_stack+0x18/0x1c)
  r7:8051ca40 r6:8050f908 r5:0000037a r4:87a8f400
[<8001b9a8>] (show_stack) from [<8005bad0>] (sched_show_task+0xe0/0xe8)
[<8005b9f0>] (sched_show_task) from [<8005cf20>] (dump_cpu_task+0x40/0x44)
  r5:00000000 r4:00000000
[<8005cee0>] (dump_cpu_task) from [<80078534>] 
(rcu_dump_cpu_stacks+0x74/0xac)
  r5:00000000 r4:8051ca40
[<800784c0>] (rcu_dump_cpu_stacks) from [<8007ba20>] 
(rcu_check_callbacks+0x2e8/0x854)
  r9:8051ca40 r8:8050e100 r7:068d8000 r6:00000235 r5:8050f9c0 r4:804fed40
[<8007b738>] (rcu_check_callbacks) from [<8007df44>] 
(update_process_times+0x44/0x6c)
  r10:00000000 r9:00000000 r8:00000000 r7:0000001d r6:87a8f400 r5:00000000
  r4:ffffe000
[<8007df00>] (update_process_times) from [<80089a08>] 
(tick_periodic+0xb0/0xb8)
  r7:0000001d r6:7fffffff r5:86dd9800 r4:8050e144
[<80089958>] (tick_periodic) from [<80089a44>] 
(tick_handle_periodic+0x34/0xac)
  r5:86dd9800 r4:ffffffff
[<80089a10>] (tick_handle_periodic) from [<8001dc04>] 
(twd_handler+0x38/0x40)
  r9:00000000 r8:86dd9800 r7:0000001d r6:87801cc0 r5:805214bc r4:00000001
[<8001dbcc>] (twd_handler) from [<80074c8c>] 
(handle_percpu_devid_irq+0x7c/0x94)
  r5:805214bc r4:805036c0
[<80074c10>] (handle_percpu_devid_irq) from [<80071214>] 
(__handle_domain_irq+0xb8/0xd8)
  r9:00000000 r8:87804800 r7:00000001 r6:804fcfc4 r5:00000000 r4:00000000
[<8007115c>] (__handle_domain_irq) from [<80009388>] 
(gic_handle_irq+0x50/0x7c)
  r9:00000000 r8:b0101100 r7:b0100100 r6:b010010c r5:87147ac8 r4:8050fb20
[<80009338>] (gic_handle_irq) from [<80009ed4>] (__irq_svc+0x54/0x90)
Exception stack(0x87147ac8 to 0x87147b10)
7ac0:                   8696e090 00000000 0000001f 00000020 86740000 
87147b78
7ae0: 86680094 86680094 87147b78 00000000 00000000 87147b24 87147b28 
87147b18
7b00: 7f4cb1ec 80017a28 20000013 ffffffff
  r9:00000000 r8:87147b78 r7:87147afc r6:ffffffff r5:20000013 r4:80017a28
[<800179d8>] (_raw_spin_lock_bh) from [<7f4cb1ec>] 
(fq_codel_dump_stats+0x68/0xd8 [sch_fq_codel_fast])
[<7f4cb184>] (fq_codel_dump_stats [sch_fq_codel_fast]) from [<802786c0>] 
(tc_fill_qdisc+0x1d0/0x284)
  r5:86740000 r4:870e0c00
[<802784f0>] (tc_fill_qdisc) from [<80278a78>] 
(qdisc_notify.isra.0+0xec/0x138)
  r10:86740000 r9:869cb800 r8:870d6308 r7:870d6306 r6:8052b780 r5:00000400
  r4:870e0c00
[<8027898c>] (qdisc_notify.isra.0) from [<80278afc>] 
(notify_and_destroy+0x38/0x50)
  r10:8052b780 r9:00000000 r8:80285a50 r7:869cba00 r6:00000000 r5:8696e000
  r4:869cb800
[<80278ac4>] (notify_and_destroy) from [<80278da8>] 
(qdisc_graft+0x294/0x360)
  r4:86740000
[<80278b14>] (qdisc_graft) from [<8027a424>] (tc_modify_qdisc+0x4a0/0x4f4)
  r10:8052b780 r9:00000000 r8:8696e000 r7:00010100 r6:870e1000 r5:870d6300
  r4:86740000
[<80279f84>] (tc_modify_qdisc) from [<802688b0>] 
(rtnetlink_rcv_msg+0x16c/0x1e4)
  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:870d7b00 r5:870d6300
  r4:000000f0
[<80268744>] (rtnetlink_rcv_msg) from [<802a37e4>] 
(netlink_rcv_skb+0x64/0xc8)
  r8:00000000 r7:870d7b00 r6:870d6300 r5:80268744 r4:870d7b00
[<802a3780>] (netlink_rcv_skb) from [<8026873c>] (rtnetlink_rcv+0x2c/0x34)
  r7:870d7b00 r6:87224000 r5:0000003c r4:870d7b00
[<80268710>] (rtnetlink_rcv) from [<802a3218>] 
(netlink_unicast+0x158/0x20c)
  r5:0000003c r4:878a8400
[<802a30c0>] (netlink_unicast) from [<802a3610>] 
(netlink_sendmsg+0x344/0x38c)
  r8:024000c0 r7:87224000 r6:0000003c r5:870d7b00 r4:87147f4c
[<802a32cc>] (netlink_sendmsg) from [<8023f680>] 
(___sys_sendmsg+0x1e8/0x22c)
  r10:87147e28 r9:87147e28 r8:00000000 r7:00000000 r6:8751ae00 r5:00000000
  r4:87147f4c
[<8023f498>] (___sys_sendmsg) from [<8023fd88>] (__sys_sendmsg+0x44/0x68)
  r10:00000000 r9:87146000 r8:80009724 r7:00000128 r6:00000000 r5:7e950ccc
  r4:8751ae00
[<8023fd44>] (__sys_sendmsg) from [<8023fdbc>] (SyS_sendmsg+0x10/0x14)
  r6:00000000 r5:00000000 r4:00000000
[<8023fdac>] (SyS_sendmsg) from [<80009560>] (ret_fast_syscall+0x0/0x48)