http://bugs.winehq.org/show_bug.cgi?id=22418
--- Comment #2 from Marc C marc@marcchamberlin.com 2010-04-19 10:52:57 --- (In reply to comment #1)
are the firefox or thunderbird processes still running aside from wineserver?
No, not always, although I have seen them show up on occasion as a defunct process when I give a ps -aux command. When that happens it is not a transitory state either but will persist until I kill the process with a kill -9 command..
Other symptoms I have noted, and should point out, is that there have been occasions when I tried to dismount the USB drive, neither ps nor lsof have reported anything amiss, but the umount command would still be refused with a "Device Busy" message. Sometimes however just lsof would report open files remained, and I will kill the associated process despite the fact that ps was not showing it. Sometimes that works, sometimes not.
I know that the only thing I had done, in these cases, was to run FirefoxPortable or ThunderbirdPortable under PortableApps, all under Wine, and all were "closed" . Nothing else could/should have been using the device, and simply waiting for awhile would not change this... When I can't find a process to kill, at that point my only option has been to reboot and hope that the shutdown process would safely dismount the USB drive...