[Qemu-devel] Minor regression with kvm ioapic, gsi >= 16

[Avi Kivity <avi@redhat.com>]

kvm-unit-tests.git x86/apic.flat is failing ioapic tests with

qemu-system-x86_64 -vnc :99 -device testdev,chardev=x -chardev null,id=x
-smp 2 -kernel ./x86/apic.flat  -serial stdio
...
ioapic interrupt: FAIL
ioapic simultaneous interrupt: FAIL

This happens because the test is invoking gsi 16, which is handled by
the non-kvm ioapic instead of the kvm ioapic.

Introduced by

commit c3388c9bd8d4f4fd841b521feed20993185d9be4
Author: Jan Kiszka <jan.kiszka@siemens.com>
Date:   Mon Feb 6 12:20:53 2012 +0100

    qemu-kvm: Fix GSI handling with in-kernel irqchip
   
    Interrupt routing with in-kernel irqchip was always a mess. Now this
    increased after latest upstream merge: we started to call ioapic_set_irq
    also for kernel-handled interrupts.
   
    Reduce this mess again by using the upstream kvm_piix3_gsi_handler. It
    is aware of the PIIX3-specific routing in KVM mode and won't call into
    the user space APIC model (as we do not raise IRQs >= ISA_NUM_IRQS with
    the PIIX3).
   
    Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
    Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>


The obvious fix would be to start using upstream's kvm-ioapic, but you
haven't, why?

-- 
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.