iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode
In the Linux kernel, the following vulnerability has been resolved: iommu/vt-d: Flush dev-IOTLB only when PCIe device is accessible in scalable mode Commit 4fc82cd907ac ("iommu/vt-d: Don't issue ATS Invalidation request when device is disconnected") relies on pci_dev_is_disconnected() to skip ATS invalidation for safely-removed devices, but it does not cover link-down caused by faults, which can still hard-lock the system. For example, if a VM fails to connect to the PCIe device, "virsh destroy" is executed to release resources and isolate the fault, but a hard-lockup occurs while releasing the group fd. Call Trace: qi_submit_sync qi_fl