iommu/vt-d: Only handle IOPF for SVA when PRI is supported

In intel_svm_set_dev_pasid(), the driver unconditionally manages the IOPF
handling during a domain transition. However, commit a86fb7717320
("iommu/vt-d: Allow SVA with device-specific IOPF") introduced support for
SVA on devices that handle page faults internally without utilizing the
PCI PRI. On such devices, the IOMMU-side IOPF infrastructure is not
required. Calling iopf_for_domain_replace() on these devices is incorrect
and can lead to unexpected failures during PASID attachment or unwinding.

Add a check for info->pri_supported to ensure that the IOPF queue logic
is only invoked for devices that actually rely on the IOMMU's PRI-based
fault handling.

Fixes: 17fce9d2336d ("iommu/vt-d: Put iopf enablement in domain attach path")
Cc: stable@vger.kernel.org
Suggested-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Link: https://lore.kernel.org/r/20260310075520.295104-1-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index fea10acd4f021f5a1b62f87e5040e00ca6e59cd9..57cd1db7207ab92ec5864dd4425b3c67cb0e24b4 100644 (file)
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -164,9 +164,12 @@ static int intel_svm_set_dev_pasid(struct iommu_domain *domain,
        if (IS_ERR(dev_pasid))
                return PTR_ERR(dev_pasid);
 
-       ret = iopf_for_domain_replace(domain, old, dev);
-       if (ret)
-               goto out_remove_dev_pasid;
+       /* SVA with non-IOMMU/PRI IOPF handling is allowed. */
+       if (info->pri_supported) {
+               ret = iopf_for_domain_replace(domain, old, dev);
+               if (ret)
+                       goto out_remove_dev_pasid;
+       }
 
        /* Setup the pasid table: */
        sflags = cpu_feature_enabled(X86_FEATURE_LA57) ? PASID_FLAG_FL5LP : 0;
@@ -181,7 +184,8 @@ static int intel_svm_set_dev_pasid(struct iommu_domain *domain,
 
        return 0;
 out_unwind_iopf:
-       iopf_for_domain_replace(old, domain, dev);
+       if (info->pri_supported)
+               iopf_for_domain_replace(old, domain, dev);
 out_remove_dev_pasid:
        domain_remove_dev_pasid(domain, dev, pasid);
        return ret;