Subject: Intel I350 mini-PCIe card (igb) on Mirabox (mvebu / Armada 370)

From: [email-masked] (Thomas Petazzoni)
Date: Tue, 8 Apr 2014 17:13:09 +0200

Hello all,

On Sun, 6 Apr 2014 16:34:08 +0100 (BST), Neil Greatorex wrote:

> From e5698a4ae6b21c7e78538e16d293123903abbb40 Mon Sep 17 00:00:00 2001
> From: Neil Greatorex <[email-masked]>
> Date: Sun, 6 Apr 2014 16:10:43 +0100
> Subject: [PATCH] irqchip: armada-370-xp: Fix releasing of MSIs
> 
> Store the value of d->hwirq in a local variable as the real value is wiped out
> by calling irq_dispose_mapping. Without this patch, the armada_370_xp_free_msi
> function would always free MSI#0, no matter what was passed to it.
> 
> Signed-off-by: Neil Greatorex <[email-masked]>
> ---
>   drivers/irqchip/irq-armada-370-xp.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/irqchip/irq-armada-370-xp.c b/drivers/irqchip/irq-armada-370-xp.c
> index 5409564..916fae2 100644
> --- a/drivers/irqchip/irq-armada-370-xp.c
> +++ b/drivers/irqchip/irq-armada-370-xp.c
> @@ -157,8 +157,10 @@ static void armada_370_xp_teardown_msi_irq(struct msi_chip *chip,
>   					   unsigned int irq)
>   {
>   	struct irq_data *d = irq_get_irq_data(irq);
> +	unsigned long hwirq = d->hwirq;
> +
>   	irq_dispose_mapping(irq);
> -	armada_370_xp_free_msi(d->hwirq);
> +	armada_370_xp_free_msi(hwirq);
>   }
> 
>   static struct irq_chip armada_370_xp_msi_irq_chip = {

Unfortunately here your patch is not sufficient to solve the problem
apparently. I've fixed another problem where the return value of
armada_370_xp_alloc_msi() (which is signed) is casted into an unsigned
irq_hw_number_t in armada_370_xp_setup_msi_irq(), but I'm still seeing
many MSIs allocated, then some freed, and finally a kernel panic.

 * Log: https://gist.github.com/tpetazzoni/10140012

 * Diff against v3.14: https://gist.github.com/tpetazzoni/10140121

Ideas? If some of you are interested in discussing this live, I'm on
#mvlinux on Freenode.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com