[PATCH v2 4/7] iommu/vt-d: Allow DMA domain attaching to rmrr locked device

From: Lu Baolu
Date: Tue Jun 11 2019 - 20:40:51 EST

We don't allow a device to be assigned to user level when it is locked
by any RMRR's. Hence, intel_iommu_attach_device() will return error if
a domain of type IOMMU_DOMAIN_UNMANAGED is about to attach to a device
locked by rmrr. But this doesn't apply to a domain of type other than
IOMMU_DOMAIN_UNMANAGED. This adds a check to fix this.

Fixes: fa954e6831789 ("iommu/vt-d: Delegate the dma domain to upper layer")
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Reported-and-tested-by: Qian Cai <cai@xxxxxx>
drivers/iommu/intel-iommu.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c
index 5251533a18a4..19c4c387a3f6 100644
--- a/drivers/iommu/intel-iommu.c
+++ b/drivers/iommu/intel-iommu.c
@@ -5139,7 +5139,8 @@ static int intel_iommu_attach_device(struct iommu_domain *domain,
int ret;

- if (device_is_rmrr_locked(dev)) {
+ if (domain->type == IOMMU_DOMAIN_UNMANAGED &&
+ device_is_rmrr_locked(dev)) {
dev_warn(dev, "Device is ineligible for IOMMU domain attach due to platform RMRR requirement. Contact your platform vendor.\n");
return -EPERM;