On Fri, Oct 26, 2007 at 02:03:19PM -0700, Stephen Hemminger wrote: > Looking at this bug: > http://bugzilla.kernel.org/show_bug.cgi?id=9149 > > Exposes some rather deep issues in the filesystem/socket/inet/tcp > layering. It seems that sys_close() zaps the file table entry, but > since each thread has a separate reference, the actual tcp_close() > doesn't happen until the last thread calls close/exits.
No. It's not about that at all. Threads in his case _share_ descriptor table and the thing he's complaining about is that another thread has removed the descriptor from their (shared) descriptor table and he's not getting notified. It's not about struct file (or socket) at all; it's all on descriptor level. The reference to struct file is held by accept() itself, _not_ by descriptor table. And he would have the same problem if the opened socket had been inherited from parent (and still opened by it) - it's really not about the damn thing getting shut down, etc. What happens is that there is a mapping from descriptors to opened files, a reference to opened file is obtained by it once per syscall and that file remains open at least until the end of syscall. Whether the descriptor you've passed remains refering to the same file is up to userland code. If you have another thread and that thread rips the descriptor out of your shared descriptor table, it's your responsibility to keep them sane and happy. close() from another thread is not a way to abort blocked accept(). Never promised to be that. Just as close() from another thread is not a way to abort blocked write() or read() or sendmsg() or... - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
