strange Bug

Björn Döbel doebel at os.inf.tu-dresden.de
Tue Nov 18 12:34:22 CET 2014


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 17.11.2014 23:00, ba_f wrote:
>> Ideally you now find the faulting address in myClient and figure
>> out where the access happens. Keep us posted if you need help
>> with that.
>> 
>> Bjoern
> 
> Oh boy...
> 
> Looking at the TCB, i see the start address 0xf118b000; and what i 
> really do care about is the address of the UTCB at f118a000, don't
> i?

Why would you care about the UTCB? We are looking for the reason your
thread caused a page fault.

[..]

> Goto f118a000, gives me the PC=15c7a8 again, where the Error
> happens.

Yep, the UTCB contains the exception message informing the exception
handler about the page fault. This is the effect of your page fault,
not the cause.

> And at 15c7a8 there is e12fff37 <=> blx r7 , which i've already
> found in MOE. But that's not what i'm looking for, is it?

This has nothing to do with MOE. When you objdump the myClient binary,
can you find the address in there? Does the binary contain blx r7 as well?

Bjoern
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1

iEYEARECAAYFAlRrLrYACgkQP5ijxgQLUNmvRwCdHXdhX+TCMZ4vNzmsFFf7tNl3
1YkAnAmkRVxcL5xUJJRhp/oAdGzQdQSC
=DxU2
-----END PGP SIGNATURE-----




More information about the l4-hackers mailing list