Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6

* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6:
  tty_port,usb-console: Fix usb serial console open/close regression
  tty: cpm_uart: use resource_size()
  tty_buffer: Fix distinct type warning
  hvc_console: Fix race between hvc_close and hvc_remove
  uartlite: Fix build on sparc.
  tty: Take a 256 byte padding into account when buffering below sub-page units
  Revert "tty: Add a new VT mode which is like VT_PROCESS but doesn't require a VT_RELDISP ioctl call"

1 files changed, 21 insertions, 10 deletions

diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
index 465185fc0f5..ba55bba151b 100644
--- a/drivers/char/hvc_console.c
+++ b/drivers/char/hvc_console.c
@@ -312,6 +312,7 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
 	spin_lock_irqsave(&hp->lock, flags);
 	/* Check and then increment for fast path open. */
 	if (hp->count++ > 0) {
+		tty_kref_get(tty);
 		spin_unlock_irqrestore(&hp->lock, flags);
 		hvc_kick();
 		return 0;
@@ -319,7 +320,7 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
 
 	tty->driver_data = hp;
 
-	hp->tty = tty;
+	hp->tty = tty_kref_get(tty);
 
 	spin_unlock_irqrestore(&hp->lock, flags);
 
@@ -336,6 +337,7 @@ static int hvc_open(struct tty_struct *tty, struct file * filp)
 		spin_lock_irqsave(&hp->lock, flags);
 		hp->tty = NULL;
 		spin_unlock_irqrestore(&hp->lock, flags);
+		tty_kref_put(tty);
 		tty->driver_data = NULL;
 		kref_put(&hp->kref, destroy_hvc_struct);
 		printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
@@ -363,13 +365,18 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
 		return;
 
 	hp = tty->driver_data;
+
 	spin_lock_irqsave(&hp->lock, flags);
+	tty_kref_get(tty);
 
 	if (--hp->count == 0) {
 		/* We are done with the tty pointer now. */
 		hp->tty = NULL;
 		spin_unlock_irqrestore(&hp->lock, flags);
 
+		/* Put the ref obtained in hvc_open() */
+		tty_kref_put(tty);
+
 		if (hp->ops->notifier_del)
 			hp->ops->notifier_del(hp, hp->data);
 
@@ -389,6 +396,7 @@ static void hvc_close(struct tty_struct *tty, struct file * filp)
 		spin_unlock_irqrestore(&hp->lock, flags);
 	}
 
+	tty_kref_put(tty);
 	kref_put(&hp->kref, destroy_hvc_struct);
 }
 
@@ -424,10 +432,11 @@ static void hvc_hangup(struct tty_struct *tty)
 	spin_unlock_irqrestore(&hp->lock, flags);
 
 	if (hp->ops->notifier_hangup)
-			hp->ops->notifier_hangup(hp, hp->data);
+		hp->ops->notifier_hangup(hp, hp->data);
 
 	while(temp_open_count) {
 		--temp_open_count;
+		tty_kref_put(tty);
 		kref_put(&hp->kref, destroy_hvc_struct);
 	}
 }
@@ -592,7 +601,7 @@ int hvc_poll(struct hvc_struct *hp)
 	}
 
 	/* No tty attached, just skip */
-	tty = hp->tty;
+	tty = tty_kref_get(hp->tty);
 	if (tty == NULL)
 		goto bail;
 
@@ -672,6 +681,8 @@ int hvc_poll(struct hvc_struct *hp)
 
 		tty_flip_buffer_push(tty);
 	}
+	if (tty)
+		tty_kref_put(tty);
 
 	return poll_mask;
 }
@@ -807,7 +818,7 @@ int hvc_remove(struct hvc_struct *hp)
 	struct tty_struct *tty;
 
 	spin_lock_irqsave(&hp->lock, flags);
-	tty = hp->tty;
+	tty = tty_kref_get(hp->tty);
 
 	if (hp->index < MAX_NR_HVC_CONSOLES)
 		vtermnos[hp->index] = -1;
@@ -819,18 +830,18 @@ int hvc_remove(struct hvc_struct *hp)
 	/*
 	 * We 'put' the instance that was grabbed when the kref instance
 	 * was initialized using kref_init().  Let the last holder of this
-	 * kref cause it to be removed, which will probably be the tty_hangup
+	 * kref cause it to be removed, which will probably be the tty_vhangup
 	 * below.
 	 */
 	kref_put(&hp->kref, destroy_hvc_struct);
 
 	/*
-	 * This function call will auto chain call hvc_hangup.  The tty should
-	 * always be valid at this time unless a simultaneous tty close already
-	 * cleaned up the hvc_struct.
+	 * This function call will auto chain call hvc_hangup.
 	 */
-	if (tty)
-		tty_hangup(tty);
+	if (tty) {
+		tty_vhangup(tty);
+		tty_kref_put(tty);
+	}
 	return 0;
 }
 EXPORT_SYMBOL_GPL(hvc_remove);