LoadLibrary during PROCESS_ATTACH

[Uwe Bonnes]

Hallo,

I am trying to debug Xilinx webpack version 5.1. If I understand things
right, the "ise" application crashed because it unloads a dll, but later
still accesses this dll.
This seems to happen, because during MODULE_InitDLL of the dll it calls a
Loadlibrary on itself. As MODULE_InitDLL sets WINE_MODREF_MARKER, and the
flow of execution in LoadLibrary checks for WINE_MODREF_MARKER before
incrementing the RefCount, the refcount gets wrong and the application
unloaded. Forcing the increment of RefCount in MODULE_LoadLibraryExA
unconditional of WINE_MODREF_MARKER makes the application continue.

Do we need the check for WINE_MODREF_MARKER in MODULE_LoadLibraryEx?
Do we still need MODULE_LoadLibraryEx at all?

Bye

[Alexandre Julliard]

Uwe Bonnes  writes:
> This seems to happen, because during MODULE_InitDLL of the dll it calls a
> Loadlibrary on itself. As MODULE_InitDLL sets WINE_MODREF_MARKER, and the
> flow of execution in LoadLibrary checks for WINE_MODREF_MARKER before
> incrementing the RefCount, the refcount gets wrong and the application
> unloaded. Forcing the increment of RefCount in MODULE_LoadLibraryExA
> unconditional of WINE_MODREF_MARKER makes the application continue.
>
> Do we need the check for WINE_MODREF_MARKER in MODULE_LoadLibraryEx?

Yes, this is needed for circular dependencies. But maybe we need to
differentiate an explicit LoadLibrary from the implicit loading of
dependencies.

[Uwe Bonnes]

> > > > > "Alexandre" == Alexandre Julliard  writes:

Alexandre> Uwe Bonnes  writes:
    >> This seems to happen, because during MODULE_InitDLL of the dll it
    >> calls a Loadlibrary on itself. As MODULE_InitDLL sets
    >> WINE_MODREF_MARKER, and the flow of execution in LoadLibrary checks
    >> for WINE_MODREF_MARKER before incrementing the RefCount, the refcount
    >> gets wrong and the application unloaded. Forcing the increment of
    >> RefCount in MODULE_LoadLibraryExA unconditional of WINE_MODREF_MARKER
    >> makes the application continue.
    >> 
    >> Do we need the check for WINE_MODREF_MARKER in MODULE_LoadLibraryEx?

Alexandre> Yes, this is needed for circular dependencies. But maybe we
    Alexandre> need to differentiate an explicit LoadLibrary from the
    Alexandre> implicit loading of dependencies.

Is appended patch appropriate?

If it finds WINE_MODREF_MARKER set in LoadLibraryEx, it corrects the
Refcount and it allows decrementing the Refcounter to 1 (but not to 0) in
MODULE_DecRefCount. At least xilinx webpack ise.exe now comes over thw first
hurdle.

Changelog:
    wine/loader/module.c: LoadLibraryExA, MODULE_DecRefCount 
    Handle Refcounting for LoadLibrary/FreeLibrary Calls 
    during MODULE_DllProcessAttach