unexpected panic in idle process (RELENG_5 2005/04/25UTC)

[Adrian Steinmann]

On Thu, 28 Apr 2005, I wrote:
   > Fatal trap 9: general protection fault while in kernel mode
   > instruction pointer     = 0x8:0xc05e8ca2
   > stack pointer           = 0x10:0xc7499d10
   > frame pointer           = 0x10:0xc7499d10
   > code segment            = base 0x0, limit 0xfffff, type 0x1b
   >                         = DPL 0, pres 1, def32 1, gran 1
   > processor eflags        = interrupt enabled, resume, IOPL = 0
   > current process         = 11 (idle)
   > [thread pid 11 tid 100003 ]
   > Stopped at      cpu_idle_default+0x5:   leave

and Doug White <dwhite at gumbysoft.com> answered on Sun, 8 May 2005:
   This is an odd one; the IA32 manual doesn't say you can take a GPF from a
   LEAVE instruction in protected mode. %ebp looks correct so I'd wonder if
   you have cooling problems or a bad processor.

Yes, odd, but maybe there is a simpler explanation: I have DDB
enabled, and the serial console may have sent a spurious break.
After nobody suggested any smart commands for db> I issued a "c"
and tadda, the system was back (albeit with the wrong time). So
this may be a red herring.

Thanks for the analysis.

Adrian