From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Auger <eric.auger@linaro.org>
Subject: Coupling between KVM_IRQFD and KVM_SET_GSI_ROUTING?
Date: Tue, 17 Jun 2014 13:39:55 +0200
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Hello,

I have a question related to KVM_IRQFD and KVM_SET_GSI_ROUTING ioctl
relationship.

When reading the KVM API documentation I do not understand there is any
dependency between KVM_IRQFD and KVM_SET_GSI_ROUTING. According to the
text it seems only the gsi field is used and interpreted as the irqchip pin.

However irqchip.c kvm_set_irq code relies on an existing and not dummy
routing table.

My question is: does anyone agree on the fact the user-side must set a
consistent routing table using KVM_SET_GSI_ROUTING before using
KVM_IRQFD? The other alternative would have been to build a default
identity GSI routing table in the kernel (gsi = irqchip.pin).

In the positive, shouldn't we clarify the KVM API documentation?

Thank you in advance

Best Regards

Eric