Subject: Re: [PATCH 15/31] KVM: PPC: Book3S HV: XIVE: Fix mapping of passthrough interrupts

From: Thomas Gleixner <[email-masked]>
Date: Fri, 14 May 2021 22:51:51 +0200

On Fri, Apr 30 2021 at 10:03, Cédric Le Goater wrote:

CC: +Marc

> PCI MSI interrupt numbers are now mapped in a PCI-MSI domain but the
> underlying calls handling the passthrough of the interrupt in the
> guest need a number in the XIVE IRQ domain.
>
> Use the IRQ data mapped in the XIVE IRQ domain and not the one in the
> PCI-MSI domain.
>
> Exporting irq_get_default_host() might not be the best solution.
>
> Cc: Thomas Gleixner <[email-masked]>
> Cc: Paul Mackerras <[email-masked]>
> Signed-off-by: Cédric Le Goater <[email-masked]>
> ---
>  arch/powerpc/kvm/book3s_xive.c | 3 ++-
>  kernel/irq/irqdomain.c         | 1 +
>  2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/kvm/book3s_xive.c b/arch/powerpc/kvm/book3s_xive.c
> index 3a7da42bed57..81b9f4fc3978 100644
> --- a/arch/powerpc/kvm/book3s_xive.c
> +++ b/arch/powerpc/kvm/book3s_xive.c
> @@ -861,7 +861,8 @@ int kvmppc_xive_set_mapped(struct kvm *kvm, unsigned long guest_irq,
>  	struct kvmppc_xive *xive = kvm->arch.xive;
>  	struct kvmppc_xive_src_block *sb;
>  	struct kvmppc_xive_irq_state *state;
> -	struct irq_data *host_data = irq_get_irq_data(host_irq);
> +	struct irq_data *host_data =
> +		irq_domain_get_irq_data(irq_get_default_host(), host_irq);
>  	unsigned int hw_irq = (unsigned int)irqd_to_hwirq(host_data);
>  	u16 idx;
>  	u8 prio;
> diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
> index d10ab1d689d5..8a073d1ce611 100644
> --- a/kernel/irq/irqdomain.c
> +++ b/kernel/irq/irqdomain.c
> @@ -481,6 +481,7 @@ struct irq_domain *irq_get_default_host(void)
>  {
>  	return irq_default_domain;
>  }
> +EXPORT_SYMBOL_GPL(irq_get_default_host);
>  
>  static void irq_domain_clear_mapping(struct irq_domain *domain,
>  				     irq_hw_number_t hwirq)