[Unionfs] Re: Unionfs BUG: null pointer dereference unionfs_setattr

[pascal at pabr.org]

Bart van der Meulen wrote:
>>  [<c0120b14>] do_page_fault+0x224/0x5c0
>>  [<c04bc302>] error_code+0x72/0x78
>>  [<c019f07a>] notify_change+0x2da/0x310
>>  [<c0188b37>] do_truncate+0x67/0x90
>>  [<c0188cb5>] do_sys_ftruncate+0x155/0x170
>>  [<c0188ceb>] sys_ftruncate64+0x1b/0x20
>>  [<c0105412>] sysenter_past_esp+0x5f/0x85

This might be related to my unlink+ftruncate bug, which
is easily reproducible:
https://bugzilla.filesystems.org/show_bug.cgi?id=633

> Can somebody give me some pointers on how to debug the problem further?

strace the application to confirm that it calls unlink
and then ftruncate on the same file descriptor.

Pascal