Re: spin lock sched lock held by 0xc25a8640 for > 5 seconds

On Thu, Nov 20, 2003 at 02:31:23PM -0500, John Baldwin wrote:
> 
> On 20-Nov-2003 Kris Kennaway wrote:
> > I updated bento last night, and it panicked after a few hours with:
> > 
> > Fatal trap 12: page fault while in kernel mode
> > cpuid = 0; apic id = 01
> > fault virtual address   = 0xe5
> > fault code              = supervisor read, page not present
> > instruction pointer     = 0x8:0xc052e219
> > stack pointer           = 0x10:0xe00d2c3c
> > frame pointer           = 0x10:0xe00d2c64
> > code segment            = base 0x0, limit 0xfffff, type 0x1b
> >                         = DPL 0, pres 1, def32 1, gran 1
> > processor eflags        = resume, IOPL = 0
> > current process         = 40 (irq29: sym0)
> > spin lock sched lock held by 0xc25a8640 for > 5 seconds
> > panic: spin lock held too long
> > cpuid = 1;
> > Debugger("panic")
> > 
> > Unfortunately it hangs there instead of breaking to DDB.
> > 
> > The instruction pointer is in:
> > 
> > ...
> > c052e000 t propagate_priority
> > c052e360 T init_turnstiles
> > ...
> > 
> > I'm currently rebuilding without WITNESS_SKIPSPIN in case this catches it.
> 
> Argh, I didn't catch that you trap 12'd before the sched_lock hang.
> Do you have INVARIANTS on?  Also, do you possibly have a kernel.debug
> around that you could try to figure out what line that IP corresponds to?

kernel trap 12 with interrupts disabled


Fatal trap 12: page fault while in kernel mode
cpuid = 0; apic id = 01
fault virtual address   = 0xe5
fault code              = supervisor read, page not present
instruction pointer     = 0x8:0xc052e219
stack pointer           = 0x10:0xe00cdc3c
frame pointer           = 0x10:0xe00cdc64
code segment            = base 0x0, limit 0xfffff, type 0x1b
                        = DPL 0, pres 1, def32 1, gran 1
processor eflags        = resume, IOPL = 0
current process         = 39 (irq28: sym1)

Another one just happened.  It again locked up and failed to enter DDB.

Kris