Revert "TTY: call tty_driver_lookup_tty unconditionally"

This reverts commit 631180aca7.

It caused problems when /dev/tty is a pty:
	https://lkml.org/lkml/2011/10/12/401

Cc: 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>
This commit is contained in:
Greg Kroah-Hartman 2011-10-19 08:33:21 -07:00
parent 5fbe46b676
commit a034070398

View File

@ -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;
struct tty_struct *tty = NULL;
int noctty, retval;
struct tty_driver *driver;
int index;
@ -1892,8 +1892,10 @@ static int tty_open(struct inode *inode, struct file *filp)
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);
@ -1901,6 +1903,7 @@ static int tty_open(struct inode *inode, struct file *filp)
tty_free_file(filp);
return PTR_ERR(tty);
}
}
if (tty) {
retval = tty_reopen(tty);