Re: 2.6.33.6-rt28 kernel oops while stressing network

[Sven-Thorsten Dietrich <thebigcorporation@gmail.com>]

On Fri, 2010-08-13 at 17:20 -0400, John Culvertson wrote:
> I changed from PREEMPT_RT to PREEMPT_DESKTOP, and now it will not
> boot.  I get the following error, then it hangs:

LOL.  Sounds like there is a little more work to be done on the .33
release.

I think you are onto something however - although I am not at the moment
blessed with the time to dig for you -
 
linkwatch_event - is that part of e1000?

If so, that's where I'd start digging.

What happens if you first disable PREEMPT_HARDIRQs,
and then next also disable PREEMPT_SOFTIRQs?

I would assume after the latter it would work just fine.

Regards,

Sven

> 
> [    9.025745] BUG: sleeping function called from invalid context at
> mm/slab.c:3266
> [    9.044859] pcnt: 1 0 in_atomic(): 1, irqs_disabled(): 0, pid: 16,
> name: events/0
> [    9.064192] Pid: 16, comm: events/0 Not tainted 2.6.33.7-rt29 #3
> [    9.076674] Call Trace:
> [    9.085224]  [<c108ed63>] ? kmem_cache_alloc+0x1b/0x99
> [    9.096780]  [<c11a8aef>] ? __alloc_skb+0x2e/0x10a
> [    9.108079]  [<c1209db2>] ? alloc_skb+0x9/0xb
> [    9.118763]  [<c120a5fd>] ? inet6_rt_notify+0x2f/0xb3
> [    9.130285]  [<c120d630>] ? fib6_add+0x21e/0x38e
> [    9.141487]  [<c120ac83>] ? __ip6_ins_rt+0x23/0x35
> [    9.152743]  [<c120536d>] ? addrconf_add_mroute+0x6c/0x72
> [    9.164855]  [<c12061f8>] ? addrconf_add_dev+0x3d/0x49
> [    9.176495]  [<c12070ed>] ? addrconf_notify+0x4f6/0x6d7
> [    9.188213]  [<c114ddff>] ? extract_entropy+0x45/0xfe
> [    9.199753]  [<c11c18a2>] ? need_resched+0x11/0x1a
> [    9.210686]  [<c11c1d97>] ? rt_do_flush+0x26/0x105
> [    9.221572]  [<c103b3dc>] ? notifier_call_chain+0x2a/0x52
> [    9.233426]  [<c103b418>] ? raw_notifier_call_chain+0x9/0xc
> [    9.244968]  [<c11af6ff>] ? netdev_state_change+0x18/0x29
> [    9.256198]  [<c11b88d7>] ? linkwatch_do_dev+0x9e/0xa7
> [    9.267208]  [<c11b8b07>] ? __linkwatch_run_queue+0xd4/0x108
> [    9.278611]  [<c11b8b58>] ? linkwatch_event+0x1d/0x22
> [    9.289437]  [<c10351e2>] ? worker_thread+0xe1/0x15e
> [    9.299891]  [<c11b8b3b>] ? linkwatch_event+0x0/0x22
> [    9.310157]  [<c1037574>] ? autoremove_wake_function+0x0/0x2d
> [    9.321305]  [<c1035101>] ? worker_thread+0x0/0x15e
> [    9.331182]  [<c103737b>] ? kthread+0x52/0x57
> [    9.340335]  [<c1037329>] ? kthread+0x0/0x57
> [    9.349248]  [<c1002dfe>] ? kernel_thread_helper+0x6/0x10
> 
> 
> On Fri, Aug 13, 2010 at 4:17 PM, Sven-Thorsten Dietrich
> <sven@thebigcorporation.com> wrote:
> >  On 08/13/2010 11:07 AM, John Culvertson wrote:
> >>
> >> Thanks for the suggestions.  I have tried the unpatched 2.6.33.7
> >> kernel, and the problem does not occur.  The hardware is a single
> >> board industrial computer with the network controllers onboard, so I
> >> cannot easily try different NICs.  I have not seen the problem occur
> >> with only one port in use, but I have not tested that long enough to
> >> be positive.
> >>
> >> One thing that may be a little odd about this computer is that both
> >> Ethernet controllers (Intel 82559) share the same PCI interrupt.
> >> Interrupt sharing should be OK, but since adjacent PCI slots in normal
> >> PCs generally use different interrupts, it may not occur often in
> >> other systems.
> >>
> >
> > Does it reproduce when you turn off PREEMPT_RT, but leave all the IRQ
> > threading options enabled?
> >
> >
> >