Commit 6a9a733e authored by Brian King's avatar Brian King Committed by Greg Kroah-Hartman
Browse files

hvcs: Fix hvcs port reference counting 



The hvcs driver only ever gets two references to the port. One
at initialization time, and one at install time. Remove the code
that was trying to do multiple port puts for each open, which
would result in more puts than gets.

Signed-off-by: default avatarBrian King <brking@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20230201195743.303163-2-brking@linux.vnet.ibm.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2115a84d

drivers/tty/hvc/hvcs.c

+0 −18
Original line number Diff line number Diff line
@@ -1215,12 +1215,9 @@ static void hvcs_hangup(struct tty_struct * tty) 
{

	struct hvcs_struct *hvcsd = tty->driver_data;

	unsigned long flags;

	int temp_open_count;

	int irq;



	spin_lock_irqsave(&hvcsd->lock, flags);

	/* Preserve this so that we know how many kref refs to put */

	temp_open_count = hvcsd->port.count;



	/*

	 * Don't kref put inside the spinlock because the destruction
@@ -1247,21 +1244,6 @@ static void hvcs_hangup(struct tty_struct * tty) 
	spin_unlock_irqrestore(&hvcsd->lock, flags);



	free_irq(irq, hvcsd);



	/*

	 * We need to kref_put() for every open_count we have since the

	 * tty_hangup() function doesn't invoke a close per open connection on a

	 * non-console device.

	 */

	while(temp_open_count) {

		--temp_open_count;

		/*

		 * The final put will trigger destruction of the hvcs_struct.

		 * NOTE:  If this hangup was signaled from user space then the

		 * final put will never happen.

		 */

		tty_port_put(&hvcsd->port);

	}

}



/*