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 <[email protected]>
---
drivers/iommu/intel-iommu.c | 32 +++++++++++++++++++++++---------
1 file changed, 23 insertions(+), 9 deletions(-)
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index e2134b13c9ae..89d82a1d50b1 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -736,12 +736,31 @@ static int iommu_dummy(struct device *dev)
return dev->archdata.iommu == DUMMY_DEVICE_DOMAIN_INFO;
}
+static bool
+is_downstream_to_pci_bridge(struct device *deva, struct device *devb)
+{
+ struct pci_dev *pdeva, *pdevb;
+
+ if (!dev_is_pci(deva) || !dev_is_pci(devb))
+ return false;
+
+ pdeva = to_pci_dev(deva);
+ pdevb = to_pci_dev(devb);
+
+ if (pdevb->subordinate &&
+ pdevb->subordinate->number <= pdeva->bus->number &&
+ pdevb->subordinate->busn_res.end >= pdeva->bus->number)
+ return true;
+
+ return false;
+}
+
static struct intel_iommu *device_to_iommu(struct device *dev, u8 *bus, u8
*devfn)
{
struct dmar_drhd_unit *drhd = NULL;
struct intel_iommu *iommu;
struct device *tmp;
- struct pci_dev *ptmp, *pdev = NULL;
+ struct pci_dev *pdev = NULL;
u16 segment = 0;
int i;
@@ -787,13 +806,7 @@ static struct intel_iommu *device_to_iommu(struct device
*dev, u8 *bus, u8 *devf
goto out;
}
- if (!pdev || !dev_is_pci(tmp))
- continue;
-
- ptmp = to_pci_dev(tmp);
- if (ptmp->subordinate &&
- ptmp->subordinate->number <= pdev->bus->number &&
- ptmp->subordinate->busn_res.end >=
pdev->bus->number)
+ if (is_downstream_to_pci_bridge(dev, tmp))
goto got_pdev;
}
@@ -2886,7 +2899,8 @@ static bool device_has_rmrr(struct device *dev)
*/
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;
}
--
2.20.1
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