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TTY: pdc_cons, fix regression in close

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The test in pdc_console_tty_close '!tty->count' was always wrong
because tty->count is decremented after tty->ops->close is called and
thus can never be zero. Hence the 'then' branch was never executed and
the timer never deleted.

This did not matter until commit 5dd5bc40f3 ("TTY: pdc_cons, use
tty_port").  There we needed to set TTY in tty_port to NULL, but this
never happened due to the bug above.

So change the test to really trigger at the last close by changing the
condition to 'tty->count == 1'.

Well, the driver should not touch tty->count at all.  It should use
tty_port->count and count open count there itself.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-and-tested-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Helge Deller <deller@gmx.de>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jiri Slaby 2012-05-05 22:49:10 +02:00 committed by Linus Torvalds
parent 1c2f954806
commit 49a5f3cf6a
1 changed files with 1 additions and 1 deletions
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2
arch/parisc/kernel/pdc_cons.c
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@ -104,7 +104,7 @@ static int pdc_console_tty_open(struct tty_struct *tty, struct file *filp)
static void pdc_console_tty_close(struct tty_struct *tty, struct file *filp)
{
if (!tty->count) {
if (tty->count == 1) {
del_timer_sync(&pdc_console_timer);
tty_port_tty_set(&tty_port, NULL);
}