Commit 631180ac authored Oct 12, 2011 by Jiri Slaby Committed by Greg Kroah-Hartman Oct 18, 2011

TTY: call tty_driver_lookup_tty unconditionally



Commit 4a2b5fdd (Move tty lookup/reopen to caller) made the call to
tty_driver_lookup_tty conditional in tty_open. It doesn't look like it
was an intention. Or if it was, it was not documented in the changelog
and the code now looks weird. For example there would be no need to
remember the tty driver and tty index. Further the condition depends
on a tty which we drop a reference of already.

If I'm looking correctly, this should not matter thanks to the locking
currently done there. Thus, tty_driver->ttys[idx] cannot change under
our hands. But anyway, it makes sense to change that to the old
behaviour.

Introduced-in: v2.6.28-rc2
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: stable <stable@vger.kernel.org>
Cc: Sukadev Bhattiprolu <sukadev@us.ibm.com>
Cc: Alan Cox <alan@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

parent 1177c0ef

drivers/tty/tty_io.c

+9 −12

Original line number	Diff line number	Diff line
		@@ -1821,7 +1821,7 @@ int tty_release(struct inode inode, struct file filp)

		static int tty_open(struct inode inode, struct file filp)
		{
		struct tty_struct *tty = NULL;
		struct tty_struct *tty;
		int noctty, retval;
		struct tty_driver *driver;
		int index;
		@@ -1892,10 +1892,8 @@ retry_open:
		return -ENODEV;
		}
		got_driver:
		if (!tty) {
		/* check whether we're reopening an existing tty */
		tty = tty_driver_lookup_tty(driver, inode, index);

		if (IS_ERR(tty)) {
		tty_unlock();
		mutex_unlock(&tty_mutex);
		@@ -1903,7 +1901,6 @@ got_driver:
		tty_free_file(filp);
		return PTR_ERR(tty);
		}
		}

		if (tty) {
		retval = tty_reopen(tty);

Admin message