tree b3959303806a6228adbbab234c474e16c81738ba
parent 201a52bea928687b7557728b176ac4f8a37d5cbd
author Stefano Stabellini <stefano.stabellini@eu.citrix.com> 1337615650 +0100
committer Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> 1337623896 -0400

xen: do not map the same GSI twice in PVHVM guests.

PV on HVM guests map GSIs into event channels. At restore time the
event channels are resumed by restore_pirqs.

Device drivers might try to register the same GSI again through ACPI at
restore time, but the GSI has already been mapped and bound by
restore_pirqs. This patch detects these situations and avoids
 mapping the same GSI multiple times.

Without this patch we get:
(XEN) irq.c:2235: dom4: pirq 23 or emuirq 28 already mapped
and waste a pirq.

CC: stable@kernel.org
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>