[patch] genirq: incorrect unlock in __setup_irq()

[patch] genirq: incorrect unlock in __setup_irq()

[Dan Carpenter]

goto out_thread is called before we take the lock.  It causes a gcc
warning: "kernel/irq/manage.c:858: warning: ‘flags’ may be used
uninitialized in this function"

Signed-off-by: Dan Carpenter <error27@gmail.com>

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index acd599a..cdcdf13 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1065,9 +1065,9 @@ mismatch:
 
 out_mask:
 	free_cpumask_var(mask);
+	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
 out_thread:
-	raw_spin_unlock_irqrestore(&desc->lock, flags);
 	if (new->thread) {
 		struct task_struct *t = new->thread;
 

Re: [patch] genirq: incorrect unlock in __setup_irq()

[Steven Rostedt]

On Thu, Mar 17, 2011 at 02:43:07PM +0300, Dan Carpenter wrote:
> goto out_thread is called before we take the lock.  It causes a gcc
> warning: "kernel/irq/manage.c:858: warning: ???flags??? may be used
> uninitialized in this function"
> 
> Signed-off-by: Dan Carpenter <error27@gmail.com>
> 
> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
> index acd599a..cdcdf13 100644
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -1065,9 +1065,9 @@ mismatch:
>  
>  out_mask:
>  	free_cpumask_var(mask);
> +	raw_spin_unlock_irqrestore(&desc->lock, flags);
>  
>  out_thread:
> -	raw_spin_unlock_irqrestore(&desc->lock, flags);

That's more than a warning fix, this is a real bug.

Acked-by: Steven Rostedt <rostedt@goodims.org>

-- Steve

>  	if (new->thread) {
>  		struct task_struct *t = new->thread;
>  
> --
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