Daniel Drake
24de9d8fdd
commitda72a379b2upstream. VMD subdevices are created with a PCI domain ID of 0x10000 or higher. These subdevices are also handled like all other PCI devices by dmar_pci_bus_notifier(). However, when dmar_alloc_pci_notify_info() take records of such devices, it will truncate the domain ID to a u16 value (in info->seg). The device at (e.g.) 10000:00:02.0 is then treated by the DMAR code as if it is 0000:00:02.0. In the unlucky event that a real device also exists at 0000:00:02.0 and also has a device-specific entry in the DMAR table, dmar_insert_dev_scope() will crash on: BUG_ON(i >= devices_cnt); That's basically a sanity check that only one PCI device matches a single DMAR entry; in this case we seem to have two matching devices. Fix this by ignoring devices that have a domain number higher than what can be looked up in the DMAR table. This problem was carefully diagnosed by Jian-Hong Pan. Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Daniel Drake <drake@endlessm.com> Fixes:59ce0515cd("iommu/vt-d: Update DRHD/RMRR/ATSR device scope caches when PCI hotplug happens") Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.