Re: [PATCH] irqchip/sifive-plic: Fix maximum priority threshold value

From: Marc Zyngier
Date: Sat Apr 11 2020 - 06:59:32 EST


On Thu, 2 Apr 2020 18:46:09 -0700
Atish Patra <atish.patra@xxxxxxx> wrote:

> As per the PLIC specification, maximum priority threshold value is 0x7
> not 0xF. Even though it doesn't cause any error in qemu/hifive unleashed,
> there may be some implementation which checks the upper bound resulting in
> an illegal access.
>
> Fixes: ccbe80bad571 (irqchip/sifive-plic: Enable/Disable external
> interrupts upon cpu online/offline)

Small nit: please write the "Fixes:" tag as documented in
process/submitting-patches.rst:

Fixes: ccbe80bad571 ("irqchip/sifive-plic: Enable/Disable external interrupts upon cpu online/offline")

(with quotes, and on a single line), as it otherwise breaks with the
lore-scrapping tooling which a bunch of us are now using.

> Signed-off-by: Atish Patra <atish.patra@xxxxxxx>
> ---
> drivers/irqchip/irq-sifive-plic.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c
> index c34fb3ae0ff8..d0a71febdadc 100644
> --- a/drivers/irqchip/irq-sifive-plic.c
> +++ b/drivers/irqchip/irq-sifive-plic.c
> @@ -56,7 +56,7 @@
> #define CONTEXT_THRESHOLD 0x00
> #define CONTEXT_CLAIM 0x04
>
> -#define PLIC_DISABLE_THRESHOLD 0xf
> +#define PLIC_DISABLE_THRESHOLD 0x7
> #define PLIC_ENABLE_THRESHOLD 0
>
> struct plic_priv {

Queued for post -rc1.

Thanks,

M.
--
Jazz is not dead. It just smells funny...