Re: [PATCH 7/17] arch/arm/common: Add missing spin_unlock_irqrestore

From: Marek Vasut
Date: Wed May 26 2010 - 13:09:00 EST


Dne St 26. kvÄtna 2010 17:56:14 Julia Lawall napsal(a):
> From: Julia Lawall <julia@xxxxxxx>
>
> Add a spin_unlock_irqrestore missing on the error path. Although the lock
> is destroyed with the rest of the sachip structure in the function
> __sa1111_remove, it still seems useful to restore the interrupt state.
>
> The semantic match that finds this problem is as follows:
> (http://coccinelle.lip6.fr/)
>
> // <smpl>
> @@
> expression E1;
> @@
>
> * spin_lock_irqsave(E1,...);
> <+... when != E1
> if (...) {
> ... when != E1
> * return ...;
> }
> ...+>
> * spin_unlock_irqrestore(E1,...);
> // </smpl>
>
> Signed-off-by: Julia Lawall <julia@xxxxxxx>
>
> ---
> Perhaps the unlock is now too early?
>
> arch/arm/common/sa1111.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/common/sa1111.c b/arch/arm/common/sa1111.c
> index a52a27c..59e38ff 100644
> --- a/arch/arm/common/sa1111.c
> +++ b/arch/arm/common/sa1111.c
> @@ -959,6 +959,7 @@ static int sa1111_resume(struct platform_device *dev)
> */
> id = sa1111_readl(sachip->base + SA1111_SKID);
> if ((id & SKID_ID_MASK) != SKID_SA1111_ID) {
> + spin_unlock_irqrestore(&sachip->lock, flags);
> __sa1111_remove(sachip);
> platform_set_drvdata(dev, NULL);
> kfree(save);

Why are "readl"s protected by spinlock anyway ? Can't we just move the locking
past the code above ?

I'm no sa1111 expert though, Russell ?

Cheers
>
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