On 2023/10/10 16:19, Tian, Kevin wrote:
From: Liu, Yi L <yi.l....@intel.com>
Sent: Monday, October 9, 2023 4:51 PM

+struct iommufd_device *iommufd_device_bind_pasid(struct iommufd_ctx
*ictx,
+                                                struct device *dev,
+                                                u32 pasid, u32 *id)
+{
+       struct iommufd_device *idev;
+       int rc;
+
+       /*
+        * iommufd always sets IOMMU_CACHE because we offer no way for
userspace
+        * to restore cache coherency.
+        */
+       if (!device_iommu_capable(dev, IOMMU_CAP_CACHE_COHERENCY))
+               return ERR_PTR(-EINVAL);
+
+       /*
+        * No iommu supports pasid-granular msi message today. Here we
+        * just check whether the parent device can do safe interrupts.
+        * Isolation between virtual devices within the parent device
+        * relies on the parent driver to enforce.
+        */
+       if (!iommufd_selftest_is_mock_dev(dev) &&
+           !msi_device_has_isolated_msi(dev)) {
+               rc = iommufd_allow_unsafe_interrupts(dev);
+               if (rc)
+                       return ERR_PTR(rc);
+       }
+

Only MemWr w/o pasid can be interpreted as an interrupt message
then we need msi isolation to protect.

yes.


But for SIOV all MemWr's are tagged with a pasid hence can never
trigger an interrupt. From this angle looks this check is unnecessary.

But the interrupts out from a SIOV virtual device do not have pasid (at
least today). Seems still need a check here if we consider this bind for
a SIOV virtual device just like binding a physical device.

--
Regards,
Yi Liu

Reply via email to