Oliver Neukum wrote: > Am Freitag, 16. Februar 2007 09:41 schrieb Samuel Ortiz: > >> One stupid question: Suppose we're in iowarrior_read(), got a pointer on >> private_data, but haven't taken the mutex yet. iowarrior_release() is >> called, locks the mutex, decrements the opened counter to 0, and then >> call iowarrior_delete(). iowarrior_read() resumes, and tries to grab >> dev->mutex, but at that point dev is NULL, and we oops. How is that case >> handled ? > > How do you close a file you are reading from? In a threaded task > you can call close and read simultaneously, but the release method > is called only when the last thread closes the fd. Well, two process would share the same dev pointer, and I was thinking of process A closing the file and thus freeing dev while process B was in read(). But the driver doesn't allow multiple multiple open(), so that's taken care of.
Cheers, Samuel. ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
