[Bug 56359] New: Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

Bug ID: 56359
           Summary: Winedbg is broken when trying to break
           Product: Wine
           Version: 8.0
          Hardware: x86-64
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: winedbg
          Assignee: [e-mail]
          Reporter: [e-mail]
      Distribution: ---

Steps to reproduce:

1. Run "wine64 winedbg notepad"
2. "c"
3. Ctrl+C (might need to do it twice if nothing changes the first time)

It broke starting from
[b1f59bc679a8c2dea18a6789a5b9b1a1ae825129] makefiles: Add support for multiple
PE architectures.

Reverting it fixes winedbg, however reverting stops helping after
[cc2cfb9b792bee681b96c5859084fd6d4d0bbed7] loader: Make the loader
position-independent on 64-bit.

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

Eric Pouech  changed:

What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |[e-mail]

--- Comment #1 from Eric Pouech  ---
Can't repro here on wine9.*

please detail which version you're using (assuming 8.0 from bugzilla ticket)
and what's the behavior you see (including console output).

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #2 from BugSeeker  ---
Created attachment 76116
  --> https://bugs.winehq.org/attachment.cgi?id=76116
winedbg log file:

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #3 from BugSeeker  ---
Reproduced on latest stable released version wine-9.0 using custom build on
RedHat7.9.

Console log with +winedbg channel is attached.

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #4 from Eric Pouech  ---
thanks for the log

what seems to happen is
- Ctrl-C is caught on console and sent to debuggee (good)
```
Ctrl-C: stopping debuggee
```
- signal handler in debuggee creates the console event dispatch thread, and
debuggee catches the thread creation events (good)
```
0118:trace:winedbg:dbg_handle_debug_event 011c:0130: create thread D
@00007F08D1B229B0
```
- but this crashes immediately, moreover at the very address of the start of
the thread
```
0118:trace:winedbg:dbg_handle_debug_event 011c:0130: exception code=c0000005
0118:trace:winedbg:dbg_handle_exception exception=c0000005 first_chance=Y
0118:trace:winedbg:dbg_handle_debug_event 011c:0130: exception code=c0000005
Unhandled exception: page fault on execute access to 0x00007f08d1b229b0 in
64-bit code (0x007f08d1b229b0).
```

(and afterwards - actually winedbg restarts because the access violation isn't
handled by first instance - the faulty address isn't present in process address
space)

as I can't repro here, I'll ask for more info (esp. to try to grasp where we
end up in this faulty address)

could send back the log (+winedbg) of the session, using the following winedbg
commands
> info share
> info maps
> p &ntdll.so!p__wine_ctrl_routine
> disas ntdll.so!p__wine_ctrl_routine
> watch * &ntdll.so!p__wine_ctrl_routine
> cont

TIA

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #5 from BugSeeker  ---
Created attachment 76117
  --> https://bugs.winehq.org/attachment.cgi?id=76117
New log with additional steps

Thanks for the quick reply!

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #6 from Eric Pouech  ---
Created attachment 76119
  --> https://bugs.winehq.org/attachment.cgi?id=76119
HACK

Aahhh.... you are not cross-compiling Wine in your custom build.
I can now reproduce locally.

The attached hack should make it work again.
A correct fix would require quite some work.

Note also that the "magic" address used here could clash will real addresses
(unlike the wow case).

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #7 from BugSeeker  ---
Patch perfectly worked. Thank you!

Following your advise the latest wine was built with minGw compiler, and I
confirm that the problem does NOT exist there.

Attached is the backtrace of notepad with cross-compiled  wine and the debug
info for some modules could not be found., e.g. ntdll ( 0 0x006fffffca5de1 in
ntdll (+0x55de1) (0000000000000000) ).

Is that expected behavior?

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #8 from BugSeeker  ---
Created attachment 76120
  --> https://bugs.winehq.org/attachment.cgi?id=76120
Cross-compiled wine backtrace

[Bug 56359] Winedbg is broken when trying to break

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=56359

--- Comment #9 from Eric Pouech  ---
> Attached is the backtrace of notepad with cross-compiled  wine and the debug
> info for some modules could not be found., e.g. ntdll ( 0 0x006fffffca5de1
> in ntdll (+0x55de1) (0000000000000000) ).
>
> Is that expected behavior?

yes this looks correct (winedbg reports the break from a dedicated thread, so
you may want to use 'bt <tid>' or 'bt all' to get a grisp if what the program
is doing).
it's likely you'll get more correct features (wrt. Windows) and more support
when cross-compiling Wine. So, if it's something you can consider, it would be
the best approach.