Hello scenario gets stuck

[Adam Lackorzynski]

On Mon Jun 03, 2013 at 16:22:54 +0200, Markus Partheymueller wrote:
> I'm having trouble booting the hello example on real hardware. The
> following config is booted via PXE:
> 
> addr   0x2000000
> exec   mparthey/foc/bootstrap -serial
> load    mparthey/foc/fiasco -serial -serial_esc -esc
> load    mparthey/foc/sigma0
> load    mparthey/foc/moe
> load    mparthey/foc/l4re
> load    mparthey/foc/hello
> 
> But it hangs after "MOE: Hello world". I can still enter the Kernel
> debugger, listing these task and thread objects:
> 
> [Objects]
>        1 f007e020 [Task   ] {KERNEL} R=2
>        6 ffdc6134 [Thread ] {KERNEL} C=0 R=1 current
>        7 fffe8f70 [Task   ] {sigma0          } R=3
>        8 ffd80134 [Thread ] {sigma0          } C=0 S=D:7 R=3
>        9 fffe8f18 [Task   ] R=3
>        a ffd83134 [Thread ] C=0 S=D:9 R=4
> 
> Backtrace on thread a yields an address 0x143d7d in moe (?), belonging to
> 
> void
> List_alloc::merge()
> {
>   List_alloc_sanity_guard __attribute__((unused)) guard(this, __func__);
>   Mem_block *c = _first;
>   while (c && c->next)
>   143d7d:       8b 00                   mov    (%eax),%eax
>   143d7f:       85 c0                   test   %eax,%eax
>   143d81:       75 ee                   jne    143d71
> <_ZN22Single_page_alloc_base5_freeEPvmb+0x51>
> _ZN22Single_page_alloc_base5_freeEPvmb():
> [...]/src/l4/pkg/moe/server/src/page_alloc.cc:109
> }
> 
> On a different machine the exact same setup works fine. Has anyone got a
> clue what goes wrong here? If I should get more information out of the
> kernel debugger, just let me know.

My first guess would be that it's pagefaulting on that instruction.
Could you check whether this is the case and what the of value eax/pfa
is?



Adam
-- 
Adam                 adam at os.inf.tu-dresden.de
  Lackorzynski         http://os.inf.tu-dresden.de/~adam/