hvc_remove() takes a spin lock first then acquires the console
semaphore. This situation can easily lead to a deadlock scenario
where we call scheduler with spin lock held.
Signed-off-by: Denis Kirjanov <k...@linux-powerpc.org>
---
drivers/tty/hvc/hvc_console.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
index b19ae36..a8d3991 100644
--- a/drivers/tty/hvc/hvc_console.c
+++ b/drivers/tty/hvc/hvc_console.c
@@ -920,17 +920,17 @@ int hvc_remove(struct hvc_struct *hp)
tty = tty_port_tty_get(&hp->port);
+ console_lock();
spin_lock_irqsave(&hp->lock, flags);
if (hp->index < MAX_NR_HVC_CONSOLES) {
- console_lock();
vtermnos[hp->index] = -1;
cons_ops[hp->index] = NULL;
- console_unlock();
}
/* Don't whack hp->irq because tty_hangup() will need to free the irq.
*/
spin_unlock_irqrestore(&hp->lock, flags);
+ console_unlock();
/*
* We 'put' the instance that was grabbed when the kref instance
--
1.8.3.1
