Re: Panic on pxeboot: kernel trap 12 with interrupts disabled

On 16 Feb, Robert Watson wrote:
> 
> I'm not sure when this began, but my pxeboot test box at work seems pretty
> unhappy.  I'll attempt to extract more debugging information, but here's a
> first pass.  Looks like map->system_map is NULL.
> 
> /boot/kernel/acpi.ko text=0x3fb40 data=0x17a4+0x116c
> syms=[0x4+0x6300+0x4+0x80f6]
> kernel trap 12 with interrupts disabled
> 
> 
> Fatal trap 12: page fault while in kernel mode
> cpuid = 0; apic id = 00
> fault virtual address   = 0x91
> fault code              = supervisor read, page not present
> instruction pointer     = 0x8:0xc07ba4b9
> stack pointer           = 0x10:0xc0c21b3c
> frame pointer           = 0x10:0xc0c21b4c
> 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         = 0 ()
> kernel: type 12 trap, code=0
> Stopped at      0xc07ba4b9:     cmpb    $0,0x91(%edx)
> db> trace
> (null)(0,c088c02e,b36,1c2011a,c1013000) at 0xc07ba4b9
> (null)(c0c21c14,c1013000,1,c0c21c18,c0c21c08) at 0xc07be108
> (null)(0,c1013000,1,0,c092ec80) at 0xc07b4f8f
> (null)(c0c21cf0,0,c1013fe9,c0001000,c1013fe9) at 0xc08096d2
> (null)(18,10,10,0,c1014000) at 0xc08092f3
> (null)(c1013fe5,c1014000,ffffffe5,c0c21d94,c07fe88c) at 0xc07f4e38
> (null)(c1014000,1,f,0,8) at 0xc0663668
> (null)(c29000) at 0xc07fe88c
> (null)() at 0xc043c85d
> db> 

My Thinkpad is crashing the same way at boot with a very recent version
of -CURRENT. The stack trace looks similar, and the fault address is
also 0x91. I'm booting of disk, so the problem isn't specific to
pxeboot.  I didn't have any problems with a kernel from Friday the 13th.