witness warning in arp processing

[Navdeep Parhar]

On 08/29/12 10:30, Vijay Singh wrote:
> All, I am seeing this warning on my 8.2 based system.
>
> taskqueue_drain with the following non-sleepable locks held:
> exclusive rw lle (lle) r = 0 (0xffffff0014dc9110) locked @ sys/netinet/in.c:1760
> KDB: stack backtrace:
> kdb_backtrace() at kdb_backtrace+0x3e
> _witness_debugger() at _witness_debugger+0x24
> witness_warn() at witness_warn+0x402
> taskqueue_drain() at taskqueue_drain+0x36
> cancel_delayed_work() at cancel_delayed_work+0x56
> set_timeout() at set_timeout+0x18
> netevent_callback() at netevent_callback+0x29
> _handle_arp_update_event() at _handle_arp_update_event+0x31
> in_arpinput() at in_arpinput+0xe92
> arpintr() at arpintr+0x255
> netisr_dispatch_src() at netisr_dispatch_src+0x14a
> netisr_dispatch() at netisr_dispatch+0x20
> ether_demux() at ether_demux+0x281
> ether_input_internal() at ether_input_internal+0x60c
> ether_nh_input() at ether_nh_input+0x1d
> netisr_dispatch_src() at netisr_dispatch_src+0x14a
> netisr_dispatch() at netisr_dispatch+0x20
> ether_input() at ether_input+0xef
> lem_rxeof() at lem_rxeof+0x6ee
> lem_handle_rxtx() at lem_handle_rxtx+0x4f
> taskqueue_run_locked() at taskqueue_run_locked+0x145
> taskqueue_thread_loop() at taskqueue_thread_loop+0x73
> fork_exit() at fork_exit+0x180
> fork_trampoline() at fork_trampoline+0xe
>
> Is this a known issue? Has it been fixed?

This is a bug in the OFED code.  The event handler it registers for the 
ARP update is not supposed to do anything that could sleep..

Regards,
Navdeep