Re : [gdbserver][WinCE][ARM] gdbserver crash: issue with GetThreadContext???

[Matthieu H <maat_h at yahoo dot fr>]

well, maybe the fix is correct???
When I apply my "patch", here is the output I have.
The debug crashs before reaching the function though :-(

$ ./gdb haret-debug.exe
GNU gdb 6.8
Copyright (C) 2008 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "--host=i686-pc-cygwin --target=arm-mingw32ce"...
(gdb) b mmu_trampoline
Breakpoint 1 at 0x2ec14: file src/wince/asmstuff.S, line 149.
(gdb) target remote 169.254.2.1:9999
Remote debugging using 169.254.2.1:9999
warning: Can not parse XML target description; XML support was disabled at 
compile time
[New Thread 1983314530]
warning: Can not parse XML library list; XML support was disabled at compile 
time
0x00000000 in ?? ()
(gdb) continue
Continuing.
[D:SMEM] smem_heap_info: static, address = 0x615030c0
Remote APIs client DLL attached
[14:11:38][haret-debug.exe][1983314530]DEB_HTC_PATH = SOFTWARE\HTC\
[A][I][haret-48][XT9IME]IME_Engine_Western: 2.2.20123425.00
[AutoTestLib] Inittialize called by SIPIME
[AutoTestLib] Fails : Open registry key : SIPIME
[A][I][haret-48][XT9IME]++ [ImeInquire]

[A][I][haret-48][XT9IME]-- [ImeInquire] elapsed time = 3

[A][I][haret-48][XT9IME]++ [ImeSetActiveContext]

[A][I][haret-48][XT9IME]++ [ImeSetActiveContext]

[A][I][haret-48][XT9IME]-- [ImeSetActiveContext] elapsed time = 4

[A][I][haret-48][XT9IME]++ [ImeSetActiveContext]

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 53f00004 m_size 12 
m_status 1

[A][I][haret-48][XT9IME]++ [eT9ImeMgr::LoadObjects]

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 53c00004 m_size 36440 
m_status 1

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 53d00004 m_size 4864 
m_status 1

[A][R][haret-48][XT9IME][InternalDBBuffer::Load] databaseFile = 
\Windows\eT9.HQD.kdb

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 5f700004 m_size 695 
m_status 1

[A][R][haret-48][XT9IME][InternalDBBuffer::Load] m_buffer = 5f700004

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 5f800004 m_size 20480 
m_status 1

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 5f900004 m_size 3200 
m_status 1

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 5fa00004 m_size 20480 
m_status 1

[A][R][haret-48][XT9IME][InternalDBBuffer::Load] databaseFile = 
\Windows\FRlsUN_xt9s.ldb

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 5fb00004 m_size 117129 
m_status 1

[A][R][haret-48][XT9IME][InternalDBBuffer::Load] m_buffer = 5fb00004

[A][R][haret-48][XT9IME][ShareMemory::create] m_pData = 5fc00004 m_size 21840 
m_status 1

[A][I][haret-48][XT9IME]-- [eT9ImeMgr::LoadObjects] elapsed time = 4124

[A][I][haret-48][XT9IME][IME] GetGlobalMode: eMode = 1

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::GetSIPStyleFromAP: unspecified

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::GetSIPStyleFromAP2: NORMAL_STATE

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::GetSIPStyleFromAP2: NORMAL_STATE

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::NotifySipSpecialUI: NORMAL_STATE

[A][I][haret-48][XT9IME][AT_WRITE_STATEVAR] CurrentET9Style: 0

[A][I][haret-48][XT9IME][IME] SetMode :1

[A][I][haret-48][XT9IME]-- [ImeSetActiveContext] elapsed time = 4182

[A][I][haret-48][XT9IME]++ [eT9ImeMgr::LoadObjects]

[A][I][haret-48][XT9IME]-- [eT9ImeMgr::LoadObjects] elapsed time = 3

[A][I][haret-48][XT9IME][IME] GetGlobalMode: eMode = 1

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::GetSIPStyleFromAP: unspecified

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::GetSIPStyleFromAP2: NORMAL_STATE

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::GetSIPStyleFromAP2: NORMAL_STATE

[A][I][haret-48][XT9IME][IME] eT9ImeMgr::NotifySipSpecialUI: NORMAL_STATE

[A][I][haret-48][XT9IME][AT_WRITE_STATEVAR] CurrentET9Style: 0

[A][I][haret-48][XT9IME][IME] SetMode :1

[A][I][haret-48][XT9IME]-- [ImeSetActiveContext] elapsed time = 4247

[D:DISP]QComSurf::convert_888_to_8888_asm - m_nWidth = 17, m_nHeight = 80, 
(uint32*)srcPtr = 0x5a06ab1c, src_stride = 4294967244d, (uint32*)ptr= 
0x54083000, m_n
StrideBytes = 128
Remote connection closed




----- Message d'origine ----
> De : Matthieu H <maat_h@yahoo.fr>
> À : gdb@sourceware.org
> Envoyé le : Jeu 10 février 2011, 11h 59min 29s
> Objet : [gdbserver][WinCE][ARM] gdbserver crash: issue with 
GetThreadContext???
> 
> Hello guys, 
> 
> I'm trying to do a remote debug using following  tools:
> HOST is a PC => gdb v6.8 compiled with gcc (i686 mingw32) under  latest cygwin 

> environment
> TARGET is a HTC Windows Mobile 6.5 phone (based  on WinCE 5.2) powered by ARM11 
>
> MSM7227 => gdbserver v6.8 compiled under  Ubuntu 10.0 with cegcc v0.55 
> (arm-mingw32ce)
> 
> I'm having an issue with  gdbserver, it is crashing immediately when I launch 
>it.
> Here are the traces I  get (without my debug messages):
> > Starting inferior
> > Process  /haret/haret-debug.exe created; pid = 2012847982
> then process crash without  further message.
> It is not even listening to connections, I even dont launch  gdb on host side, 
>it 
>
> crashs by itself without any help :-)
> 
> I put some  traces, and I figured out that the call to function 
> GetThreadContext(), in  arm_get_thread_context() in win32-arm-low.c was somehow 
>
> corrupting the  "current_inferior" ptid global data, causing the function 
> "current_inferior_ptid()" to return 0.
> 
> The program crashes in  child_fetch_inferior_registers() at this line:
> > win32_thread_info *th =  thread_rec (current_inferior_ptid (), TRUE);
> Call to current_inferior_pid()  returns 0, causing thread_rec(...) to crash 
>when 
>
> trying to get the thread  data context. 
> 
> I tried many things:
> - looking for known bugs in gdb  bug database (nothing found)
> - looking for this kind of bug in gdb mailing  list (nothing found)
> - looking the different revisions of source code in gdb  CVS and trying 
>different 
>
> modifications (not worked)
> - i tried with  gbdserver v6.7, v6.8, v7.2 but no success
> 
> I'm running out of solutions  here...
> The only workaround I found was to replace this line by this one: 
> /* Fetch register(s) from the current thread context.  */
> static  void
> child_fetch_inferior_registers (struct regcache *regcache, int  r)
> {
>   int regno;
> - win32_thread_info *th = thread_rec  (current_inferior_ptid (), TRUE);
> + win32_thread_info *th = thread_rec  (current_inferior_ptid (), FALSE);
> 
> This tells gdbserver not to load the  context of the thread (=it does not call 

> GetThreadContext() so  "current_inferior" is not corrupted)
> It's a dirty workaround cause I believe  the thread context is required when 
> debugging!
> But at least I can connect  using gdb on my host PC.
> The program crash later anyway, I believe the  workaround is not good :-)
> 
> Can you please help me?
> Any idea what could  be wrong?
> 
> GetThreadContext returns value "TRUE", meaning function  succeed... maybe 
> arguments are wrong... but I'm not expert in gdb enough to  say that.
> 
> Many thanks for your kind help
> 
> Matthieu
> 
> 
> 
>