strange Bug

ba_f ba_f at rbg.informatik.tu-darmstadt.de
Mon Nov 17 23:00:49 CET 2014


> 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?

  jdb: t59
  thread  :  59 <0xf118b000>      CPU: 0:0        prio: ff  mode: Con
  state   : 008 rcv_wait
  wait for: ---   polling:        rcv descr: 00000000
  lcked by:                       timeout  :
  cpu time:   1.000 ms            timeslice: 9000/-1 �s
  pager   : [C:   5] D:  54       task     : D:  58
  exc-hndl: [C:   5] D:  54       UTCB     : f118a000/b3000000
  vCPU    : ---
  vCPU    : ---

  PC=b0002b8c USP=b1007dc0
  [0] 00000001 00000001 fffff80f 04000000 [4] 00000000 b001910c 00000000 
b00190e4
  [8] b1007e14 00000000 000000ff b0019284 [c] 00000007 b0002b8c fffffff8 
00000010



  f118be6c f1195000 f00101c0 f00101c4 f118b000 200000d3 f118b000 f005f6e8 
f00640e0
     e80  f1195000 f118b014 f005f6e8 ffff0440 00000000 f0010b78 f005f6b8 
00000001
     ea0  f11f6000 f118a000 00000008 f00640e0 f118bef8 f118bec8 f0054590 
f118b000
     ec0  00000000 f001e378 200000d3 f118b008 f1195040 f001e2e4 f005f6e8 
f118a000
     ee0  00000001 00330007 fffe0002 f118a000 00000000 00000001 f0054590 
f001c4b0
     f00  00000000 fff32011 f118bf4c f003581c ff000000 00000001 00060450 
00000003
     f20  00000000 04000000 00000001 f118bfb8 f118bf40 00000001 f118b000 
f0022090
     f40  00000001 00000000 04000000 f118bfb8 00000003 00000000 00000000 
f118bfb8
  tcb: 59 f118b11c [Thread ] {#myClient       } C=0 S=D:58 R=1



Well, i dumped f118b000 and found f118a000.


  f118b000:f0055f80 00000008        0        0        0        0 f118be68 
        0
  f118b020:b3000000 f118a000 f12e45ec        0        0 f118b000        0 
        0
  f118a040:b1000000 b1007fff        0 fffff800 b3000000 b3000fff        0 
fffff800


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

  f118a000:      -1 0015c7a8 0000f000        0        0 0004000c 00414000 
0000003e
  f118a020:00414037 b001efff        0 fffff800 b0100000 b013ffff        0 
fffff800
  f118a040:b1000000 b1007fff        0 fffff800 b3000000 b3000fff        0 
fffff800



Anyway, thank u again.
ba_f






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