[ Upstream commit 39d630e332144028f56abba83d94291978e72df1 ]

PASID allocator uses IDR which is exclusive for the end of the
allocation range. There is no need to decrement pasid_max.

Fixes: af395073 ("iommu/vt-d: Apply global PASID in SVA")
Reported-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NJacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: NEric Auger <eric.auger@redhat.com>
Signed-off-by: NLu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: NJoerg Roedel <jroedel@suse.de>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NYang Yingliang <yangyingliang@huawei.com>