Re: [Bug 7505] Linux-2.6.18 fails to boot on AMD64 machine

[Andrew Morton <akpm@osdl.org>]

On Wed, 20 Dec 2006 04:59:19 -0500
Chuck Ebbert <76306.1226@compuserve.com> wrote:

> > On 12/19/06, Chuck Ebbert <76306.1226@compuserve.com> wrote:
> > > So an external interrupt occurred, the system tried to use interrupt
> > > descriptor #39 decimal (irq 7), but the descriptor was invalid.
> > 
> > but the irq is disabled at that time.
> > 
> > can you use attached diff to verify if the irq is enable somehow?
> 
> But it seems interrupts are on--look at the flags:
> 
>         RSP: 0018:ffffffff803cdf68  EFLAGS: 00010246
> 

down_write()->__down_write()->__down_write_nested()->spin_unlock_irq()->dead

Could someone please test this?


--- a/lib/rwsem-spinlock.c~a
+++ a/lib/rwsem-spinlock.c
@@ -195,13 +195,14 @@ void fastcall __sched __down_write_neste
 {
 	struct rwsem_waiter waiter;
 	struct task_struct *tsk;
+	unsigned long flags;
 
-	spin_lock_irq(&sem->wait_lock);
+	spin_lock_irqsave(&sem->wait_lock, flags);
 
 	if (sem->activity == 0 && list_empty(&sem->wait_list)) {
 		/* granted */
 		sem->activity = -1;
-		spin_unlock_irq(&sem->wait_lock);
+		spin_unlock_irqrestore(&sem->wait_lock, flags);
 		goto out;
 	}
 
@@ -216,7 +217,7 @@ void fastcall __sched __down_write_neste
 	list_add_tail(&waiter.list, &sem->wait_list);
 
 	/* we don't need to touch the semaphore struct anymore */
-	spin_unlock_irq(&sem->wait_lock);
+	spin_unlock_irqrestore(&sem->wait_lock, flags);
 
 	/* wait to be given the lock */
 	for (;;) {
_