[Bug 24185] New: Deadlock in vectored exception handling

[wine-bugs at winehq.org]

http://bugs.winehq.org/show_bug.cgi?id=24185

           Summary: Deadlock in vectored exception handling
           Product: Wine
           Version: 1.3.0
          Platform: x86
        OS/Version: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: ntdll
        AssignedTo: wine-bugs at winehq.org
        ReportedBy: krissn at op.pl


When running MapSource (a Garmin GPS map manager) I noticed that the
application will hang soon after starting. The hang occurs at random time when
MapSource is drawing the map on the screen. The log output clearly indicates a
classic deadlock:

err:ntdll:RtlpWaitForCriticalSection section 0x7efec6e0
"/var/tmp/portage/app-emulation/wine-1.3.0/work/wine-1.3.0/dlls/ntdll/exception.c:
vectored_handlers_section" wait timed out in thread 001b, blocked by 0009,
retrying (60 sec)
err:ntdll:RtlpWaitForCriticalSection section 0x7e9f3d80
"/var/tmp/portage/app-emulation/wine-1.3.0/work/wine-1.3.0/dlls/gdi32/gdiobj.c:
gdi_section" wait timed out in thread 0009, blocked by 001b, retrying (60 sec)

Some deeper investigation revealed that the GDI's DIB exception handler is
involved in this problem. Here's the scenario:

1. Thread A calls a GDI function. The function takes the "gdi_section".
2. Thread B raises an exception (could be a C++ exception). The
call_vectored_handlers() function is called to call the handlers. The
"vectored_handlers_section" is entered.
3. Thread B execues the X11DRV_DIB_FaultHandler(), which eventually leads to a
call to GetObjectW() and in turn GDI_GetObjPtr(). The last one blocks on
"gdi_section".
4. Thread A throws an Access Violation exception in the DIB functions. The
call_vectored_handlers() function is called, but this time it blocks on
"vectored_handlers_section"

A possible solution would be to replace the "vectored_handlers_section" by a RW
lock. This would ensure that multiple exception handlers are called
simultaneously while still maintaining consistency in case the vectored
exception handler list needs to be changed.

-- 
Configure bugmail: http://bugs.winehq.org/userprefs.cgi?tab=email
Do not reply to this email, post in Bugzilla using the
above URL to reply.
------- You are receiving this mail because: -------
You are watching all bug changes.