When a domain is attached to a device, the required cache tags are assigned to the domain so that the related caches can be flushed whenever it is needed. The device TLB cache tag is created based on whether the ats_enabled field of the device's iommu data is set. This creates an ordered dependency between cache tag assignment and ATS enabling. The device TLB cache tag would not be created if device's ATS is enabled after the cache tag assignment. This causes devices with PCI ATS support to malfunction. The ATS control is exclusively owned by the iommu driver. Hence, move cache_tag_assign_domain() after PCI ATS enabling to make sure that the device TLB cache tag is created for the domain. Fixes: 3b1d9e2b2d68 ("iommu/vt-d: Add cache tag assignment interface") Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Reviewed-by: Kevin Tian <kevin.tian@intel.com> Link: https://lore.kernel.org/r/20240620062940.201786-1-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel <jroedel@suse.de>
Linux kernel ============ There are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. Please read Documentation/admin-guide/README.rst first. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. The formatted documentation can also be read online at: https://www.kernel.org/doc/html/latest/ There are various text files in the Documentation/ subdirectory, several of them using the reStructuredText markup notation. 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.
Description
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%