From: Eric Auger <eric.auger@redhat.com>
Date: Mon, 3 Jun 2019 08:53:33 +0200
Subject: iommu/vt-d: Handle RMRR with PCI bridge device scopes
Git-commit: e143fd4598ddf7401d3699957cd59ceb5426d53d
Patch-mainline: v5.3-rc1
References: bsc#1140961

When reading the vtd specification and especially the
Reserved Memory Region Reporting Structure chapter,
it is not obvious a device scope element cannot be a
PCI-PCI bridge, in which case all downstream ports are
likely to access the reserved memory region. Let's handle
this case in device_has_rmrr.

Fixes: ea2447f700ca ("intel-iommu: Prevent devices with RMRRs from being placed into SI Domain")

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---
 drivers/iommu/intel-iommu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -2825,7 +2825,8 @@ static bool device_has_rmrr(struct devic
 		 */
 		for_each_active_dev_scope(rmrr->devices,
 					  rmrr->devices_cnt, i, tmp)
-			if (tmp == dev) {
+			if (tmp == dev ||
+			    is_downstream_to_pci_bridge(dev, tmp)) {
 				rcu_read_unlock();
 				return true;
 			}