From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paolo Bonzini <pbonzini@redhat.com>
Subject: Re: [PATCH 1/7] KVM: api: add kvm_irq_routing_extended_msi
Date: Mon, 6 Jul 2015 17:54:55 +0200
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To: Andre Przywara <andre.przywara@arm.com>, Pavel Fedin <p.fedin@samsung.com>, 'Christoffer Dall' <christoffer.dall@linaro.org>
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On 06/07/2015 17:37, Andre Przywara wrote:
> Wouldn't:
>     if (kvm_vm_check_extension(s, KVM_CAP_MSI_DEVID)) {
>         kroute.flags = KVM_MSI_VALID_DEVID;
>         kroute.u.msi.devid = (pci_bus_num(dev->bus) << 8) | dev->devfn;
>     }
> 
> be saner (without a global variable)?
> That would make the interface more consistent, with a new flag being
> protected by a new capability.

I agree that your version is niceer, but you still need to cache the
kvm_vm_check_extension result... in a global variable. :)

Paolo