viocons: BKL locking

For some weird reason I can't ascertain (translation "I think its
broken") the viocons driver calls directly into the n_tty ldisc code even
if another ldisc is in use. It'll probably break if you do that but I'm
just fixing the locking and adding a comment that its horked.

Signed-off-by: Alan Cox <alan@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/char/viocons.c b/drivers/char/viocons.c
index 8de6b95..9319c63 100644 (file)
--- a/drivers/char/viocons.c
+++ b/drivers/char/viocons.c
@@ -704,8 +704,11 @@ static int viotty_ioctl(struct tty_struct *tty, struct file *file,
        case KDSKBLED:
                return 0;
        }
-
-       return n_tty_ioctl(tty, file, cmd, arg);
+       /* FIXME: WTF is this being called for ??? */
+       lock_kernel();
+       ret =  n_tty_ioctl(tty, file, cmd, arg);
+       unlock_kernel();
+       return ret;
 }
 
 /*