possible locking bug in tty_open

[Arnd Bergmann]

While playing some more with my TTY BKL patches, I stumbled over
what looks like a bug in tty_open, introduced in e8c6210 
"tty: push the BKL down into the handlers a bit":

After the "retry_open:" label, we first get the tty_mutex
and then the BKL. However a the end of tty_open, we jump
back to retry_open with the BKL still held. If we run into
this case, the tty_open function will be left with the BKL
still held.

It may be impossible to actually trigger this bug, because
the path is only taken if a tty driver open function returns
-ERESTARTSYS without setting signal_pending().

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/