Re: general protection fault panic

On Monday, March 26, 2012 4:45:30 pm Steve Kargl wrote:
> On Mon, Mar 26, 2012 at 04:17:50PM -0400, John Baldwin wrote:
> > On Monday, March 26, 2012 1:59:18 pm Steve Kargl wrote:
> > > On Mon, Mar 26, 2012 at 01:53:25PM -0400, John Baldwin wrote:
> > > > On Monday, March 26, 2012 1:41:55 pm Steve Kargl wrote:
> > > > > On Mon, Mar 26, 2012 at 01:18:37PM -0400, John Baldwin wrote:
> > > > > > On Monday, March 26, 2012 12:21:29 pm Steve Kargl wrote:
> > > > > > 
> > > > > > You know your APIC ID is 0, so you should be able to find the IRQ 
for vector 
> > > > > > 51 from here in apic_idt_to_irq():
> > > > > > 
> > > > > > 	irq = lapics[apic_id].la_ioint_irqs[vector - APIC_IO_INTS];
> > > > > > 
> > > > > > Your apic_id is 0, and APIC_IO_INTS is 48, so you should be able 
to do this
> > > > > > in kgdb:
> > > > > > 
> > > > > > p lapics[0].la_ioint_irqs[3]
> > > > > > 
> > > > > > That should give you an index, and intr_lookup_source() just does 
an array
> > > > > > lookup.  However, I'd be curious to see what the assembly looks 
like
> > > > > > (x/10i $rip at this frame).
> > > > > > 
> > > > > 
> > > > > 
> > > > > (kgdb) p lapics[0].la_ioint_irqs[3]
> > > > > $1 = 16
> > > > > (kgdb) frame 27
> > > > > #27 0xffffffff806dc186 in acpi_cpu_c1 ()
> > > > >     at /usr/src/sys/amd64/acpica/acpi_machdep.c:97
> > > > 
> > > > Sorry, I meant down at the frame that faulted (frame 7 in this case).
> > > > 
> > > 
> > > (kgdb) frame 7
> > > #7  0xffffffff80751232 in lapic_handle_intr (vector=51, 
> > >     frame=0xffffff8000229a70) at /usr/src/sys/x86/x86/local_apic.c:777
> > > 777     {
> > > (kgdb) x/10i $rip
> > > 0xffffffff80751232 <lapic_handle_intr+2>:       stos   %eax,%es:(%rdi)
> > > 0xffffffff80751233 <lapic_handle_intr+3>:       (bad)  
> > > 0xffffffff80751234 <lapic_handle_intr+4>:       pop    %rbp
> > > 0xffffffff80751235 <lapic_handle_intr+5>:       pop    %rsi
> > > 0xffffffff80751236 <lapic_handle_intr+6>:       fsubr  %st(3),%st
> > > 0xffffffff80751238 <lapic_handle_intr+8>:       (bad)  
> > > 0xffffffff80751239 <lapic_handle_intr+9>:       or     $0xac1ae6b3,%eax
> > > 0xffffffff8075123e <lapic_handle_intr+14>:      out    %eax,$0x19
> > > 0xffffffff80751240 <lapic_handle_intr+16>:
> > >     jl     0xffffffff8075125e <lapic_handle_intr+46>
> > > 0xffffffff80751242 <lapic_handle_intr+18>:      adc    
%r12d,0xc6aa671(%rdi)
> > 
> > Looks like the instruction pointer is busted.  Try doing 'x/10i 
lapic_handle_intr'.
> > I suspect you will not see 'lapic_handle_intr+2' as a valid instruction 
offset. :(
> > 
> 
> I'm assuming you want this in frame 7
> 
> (kgdb) frame 7
> #7  0xffffffff80751232 in lapic_handle_intr (vector=51, 
>     frame=0xffffff8000229a70) at /usr/src/sys/x86/x86/local_apic.c:777
> (kgdb) x/10i lapic_handle_intr
> 0xffffffff80751230 <lapic_handle_intr>: sbb    $0xa7,%al
> 0xffffffff80751232 <lapic_handle_intr+2>:       stos   %eax,%es:(%rdi)
> 0xffffffff80751233 <lapic_handle_intr+3>:       (bad)  
> 0xffffffff80751234 <lapic_handle_intr+4>:       pop    %rbp
> 0xffffffff80751235 <lapic_handle_intr+5>:       pop    %rsi
> 0xffffffff80751236 <lapic_handle_intr+6>:       fsubr  %st(3),%st
> 0xffffffff80751238 <lapic_handle_intr+8>:       (bad)  
> 0xffffffff80751239 <lapic_handle_intr+9>:       or     $0xac1ae6b3,%eax
> 0xffffffff8075123e <lapic_handle_intr+14>:      out    %eax,$0x19
> 0xffffffff80751240 <lapic_handle_intr+16>:
>     jl     0xffffffff8075125e <lapic_handle_intr+46>

Hmmm, odd.  In this case the frame doesn't matter (global symbol).

Are you sure you are using the correct kernel.debug file?

-- 
John Baldwin