On Mon, 21 Jan 2019 15:33:39 +0000,
Julien Thierry <[email protected]> wrote:
>
> Provide a higher priority to be used for pseudo-NMIs. When such an
> interrupt is received, keep interrupts fully disabled at CPU level to
> prevent receiving other pseudo-NMIs while handling the current one.
>
> Signed-off-by: Julien Thierry <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Jason Cooper <[email protected]>
> Cc: Marc Zyngier <[email protected]>
> ---
> drivers/irqchip/irq-gic-v3.c | 42 ++++++++++++++++++++++++++++++++++++------
> 1 file changed, 36 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> index 5374b43..4df1e94 100644
> --- a/drivers/irqchip/irq-gic-v3.c
> +++ b/drivers/irqchip/irq-gic-v3.c
> @@ -41,6 +41,8 @@
>
> #include "irq-gic-common.h"
>
> +#define GICD_INT_NMI_PRI (GICD_INT_DEF_PRI & ~0x80)
> +
> #define FLAGS_WORKAROUND_GICR_WAKER_MSM8996 (1ULL << 0)
>
> struct redist_region {
> @@ -381,12 +383,45 @@ static u64 gic_mpidr_to_affinity(unsigned long mpidr)
> return aff;
> }
>
> +static inline void gic_deactivate_unexpected_irq(u32 irqnr)
Same remark as on some other patches: you should be able to drop the
inline attribute without any ill effect. I'd also like this to be
renamed "gic_deactivate_spurious", or something similar.
> +{
> + if (static_branch_likely(&supports_deactivate_key)) {
> + if (irqnr < 8192)
> + gic_write_dir(irqnr);
> + } else {
> + gic_write_eoir(irqnr);
> + }
> +}
> +
> +static inline void gic_handle_nmi(u32 irqnr, struct pt_regs *regs)
> +{
> + int err;
> +
> + if (static_branch_likely(&supports_deactivate_key))
> + gic_write_eoir(irqnr);
> + /*
> + * Leave the PSR.I bit set to prevent other NMIs to be
> + * received while handling this one.
> + * PSR.I will be restored when we ERET to the
> + * interrupted context.
> + */
> + err = handle_domain_nmi(gic_data.domain, irqnr, regs);
So this is the point where we start having a dependency on the NMI
series. We definitely need to start talking merge strategy.
> + if (err)
> + gic_deactivate_unexpected_irq(irqnr);
> +}
> +
> static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs
> *regs)
> {
> u32 irqnr;
>
> irqnr = gic_read_iar();
>
> + if (gic_supports_nmi() &&
> + unlikely(gic_read_rpr() == GICD_INT_NMI_PRI)) {
> + gic_handle_nmi(irqnr, regs);
> + return;
> + }
> +
> if (gic_prio_masking_enabled()) {
> gic_pmr_mask_irqs();
> gic_arch_enable_irqs();
> @@ -403,12 +438,7 @@ static asmlinkage void __exception_irq_entry
> gic_handle_irq(struct pt_regs *regs
> err = handle_domain_irq(gic_data.domain, irqnr, regs);
> if (err) {
> WARN_ONCE(true, "Unexpected interrupt received!\n");
> - if (static_branch_likely(&supports_deactivate_key)) {
> - if (irqnr < 8192)
> - gic_write_dir(irqnr);
> - } else {
> - gic_write_eoir(irqnr);
> - }
> + gic_deactivate_unexpected_irq(irqnr);
> }
> return;
> }
> --
> 1.9.1
>
With the above addressed,
Acked-by: Marc Zyngier <[email protected]>
M.
--
Jazz is not dead, it just smell funny.
