From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pavel Fedin <p.fedin@samsung.com>
Subject: RE: [RFC 0/6] KVM: arm/arm64: gsi routing support
Date: Wed, 24 Jun 2015 15:20:33 +0300
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To: 'Eric Auger' <eric.auger@linaro.org>, 'Andre Przywara' <andre.przywara@arm.com>, eric.auger@st.com
Cc: 'Marc Zyngier' <Marc.Zyngier@arm.com>, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org
List-Id: kvmarm@lists.cs.columbia.edu

 Hello!

> What I can simply do is preventing any non identity mapping for irqchip
> routing entries, ie. gsi != irqchip.pin. This fixes the problem of
> KVM_IRQ_LINE. This check can happen in arm kvm_set_routing_entry() and
> that's it.

 You cannot fix problem of KVM_IRQ_LINE because anyway with this ioctl on ARM you should OR your
value with (1 << 24), so this is actually not plain GSI any more.
 KVM_IRQ_LINE is never used for triggering MSIs, so i think the easiest thing to do is to just leave
it doing what it does.

 As to irqchip routing of irqfd's, why not? By default all GSIs would be SPIs, then this can be
changed by userspace, or reverted back... Who cares? When using direct mapping qemu never calls
routing functions, so it's OK.


Kind regards,
Pavel Fedin
Expert Engineer
Samsung Electronics Research center Russia