'panic: spin lock held too long' at boot

[Sergey S. Ropchan]

Hello, same situation on 5.4 - STABLE - Dual XEON

spin lock smp rendezvous held by 0xcb089780 for > 5 seconds
panic: spin lock held too long
cpuid = 2

CPU: Intel(R) Xeon(TM) CPU 2.40GHz (2392.25-MHz 686-class CPU)
  Origin = "GenuineIntel"  Id = 0xf27  Stepping = 7

Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
  Hyperthreading: 2 logical CPUs
real memory  = 4160225280 (3967 MB)
avail memory = 4072288256 (3883 MB)
ACPI APIC Table: <PTLTD    APIC  >
FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
 cpu0 (BSP): APIC ID:  0
 cpu1 (AP): APIC ID:  1
 cpu2 (AP): APIC ID:  6
 cpu3 (AP): APIC ID:  7

> On Friday 06 May 2005 11:44 am, Kris Kennaway wrote:
> > The following has happened twice recently while booting 6.0 on a
> > 12-processor e4500:
> >
> > [...]
> > Waiting 8 seconds for SCSI devices to settle
> > SMP: AP CPU #11 Launched!
> > SMP: AP CPU #10 Launched!
> > SMP: AP CPU #9 Launched!
> > SMP: AP CPU #8 Launched!
> > SMP: AP CPU #7 Launched!
> > SMP: AP CPU #6 Launched!
> > SMP: AP CPU #5 Launched!
> > SMP: AP CPU #4 Launched!
> > SMP: AP CPU #3 Launched!
> > SMP: AP CPU #2 Launched!
> > SMP: AP CPU #1 Launched!
> > panic: spin lock held too long0xffffff813e774730 foor >5 seecons
> > cpuid = 11
> > KDB: enter: panic
> > [hangs]
> >
> > Any ideas?
> 
> Could be related to how the idle loop is coded.  Try hacking on it so that it 
> does a try lock of sched_lock and only calls mi_switch() if it succeeds, 
> otherwise loop around and call sched_runnable() again.
>