Commit a2cdecdf authored by Yi Liu's avatar Yi Liu Committed by Jason Gunthorpe
Browse files

iommu/vt-d: Enhance capability check for nested parent domain allocation 

This adds the scalable mode check before allocating the nested parent domain
as checking nested capability is not enough. User may turn off scalable mode
which also means no nested support even if the hardware supports it.

Fixes: c97d1b20 ("iommu/vt-d: Add domain_alloc_user op")
Link: https://lore.kernel.org/r/20231024150011.44642-1-yi.l.liu@intel.com


Signed-off-by: default avatarYi Liu <yi.l.liu@intel.com>
Reviewed-by: default avatarLu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 55a01657

drivers/iommu/intel/iommu.c

+1 −1
Original line number Diff line number Diff line
@@ -4095,7 +4095,7 @@ intel_iommu_domain_alloc_user(struct device *dev, u32 flags, 
	if (!iommu)

		return ERR_PTR(-ENODEV);



	if ((flags & IOMMU_HWPT_ALLOC_NEST_PARENT) && !ecap_nest(iommu->ecap))

	if ((flags & IOMMU_HWPT_ALLOC_NEST_PARENT) && !nested_supported(iommu))

		return ERR_PTR(-EOPNOTSUPP);



	dirty_tracking = (flags & IOMMU_HWPT_ALLOC_DIRTY_TRACKING);

drivers/iommu/intel/iommu.h

+2 −0
Original line number Diff line number Diff line
@@ -544,6 +544,8 @@ enum { 
				 ecap_pasid((iommu)->ecap))

#define ssads_supported(iommu) (sm_supported(iommu) &&                 \

				ecap_slads((iommu)->ecap))

#define nested_supported(iommu)	(sm_supported(iommu) &&			\

				 ecap_nest((iommu)->ecap))



struct pasid_entry;

struct pasid_state_entry;