plip: replace spin_lock_irq with spin_lock_irqsave in irq context

Plip uses spin_lock_irq/spin_unlock_irq in its IRQ handler (called from
parport IRQ handler), the latter enables interrupts without parport
subsystem IRQ handler expecting it.

The bug can be seen if you compile kernel with lock dependency checking
and use plip --- it produces a warning.

This patch changes it to spin_lock_irqsave/spin_lock_irqrestore, so that
it doesn't enable interrupts when already disabled.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Mikulas Patocka 2008-04-01 01:22:45 +02:00 committed by Linus Torvalds
parent a9edadbf79
commit cabce28ec0

View File

@ -903,17 +903,18 @@ plip_interrupt(void *dev_id)
struct net_local *nl;
struct plip_local *rcv;
unsigned char c0;
unsigned long flags;
nl = netdev_priv(dev);
rcv = &nl->rcv_data;
spin_lock_irq (&nl->lock);
spin_lock_irqsave (&nl->lock, flags);
c0 = read_status(dev);
if ((c0 & 0xf8) != 0xc0) {
if ((dev->irq != -1) && (net_debug > 1))
printk(KERN_DEBUG "%s: spurious interrupt\n", dev->name);
spin_unlock_irq (&nl->lock);
spin_unlock_irqrestore (&nl->lock, flags);
return;
}
@ -942,7 +943,7 @@ plip_interrupt(void *dev_id)
break;
}
spin_unlock_irq(&nl->lock);
spin_unlock_irqrestore(&nl->lock, flags);
}
static int