Jacob Pan
7e00b52c8c
[ Upstream commit194b3348bd] On platforms that do not support IOMMU Extended capability bit 0 Page-walk Coherency, CPU caches are not snooped when IOMMU is accessing any translation structures. IOMMU access goes only directly to memory. Intel IOMMU code was missing a flush for the PASID table directory that resulted in the unrecoverable fault as shown below. This patch adds clflush calls whenever allocating and updating a PASID table directory to ensure cache coherency. On the reverse direction, there's no need to clflush the PASID directory pointer when we deactivate a context entry in that IOMMU hardware will not see the old PASID directory pointer after we clear the context entry. PASID directory entries are also never freed once allocated. DMAR: DRHD: handling fault status reg 3 DMAR: [DMA Read NO_PASID] Request device [00:0d.2] fault addr 0x1026a4000 [fault reason 0x51] SM: Present bit in Directory Entry is clear DMAR: Dump dmar1 table entries for IOVA 0x1026a4000 DMAR: scalable mode root entry: hi 0x0000000102448001, low 0x0000000101b3e001 DMAR: context entry: hi 0x0000000000000000, low 0x0000000101b4d401 DMAR: pasid dir entry: 0x0000000101b4e001 DMAR: pasid table entry[0]: 0x0000000000000109 DMAR: pasid table entry[1]: 0x0000000000000001 DMAR: pasid table entry[2]: 0x0000000000000000 DMAR: pasid table entry[3]: 0x0000000000000000 DMAR: pasid table entry[4]: 0x0000000000000000 DMAR: pasid table entry[5]: 0x0000000000000000 DMAR: pasid table entry[6]: 0x0000000000000000 DMAR: pasid table entry[7]: 0x0000000000000000 DMAR: PTE not present at level 4 Cc: <stable@vger.kernel.org> Fixes:0bbeb01a4f("iommu/vt-d: Manage scalalble mode PASID tables") Reviewed-by: Kevin Tian <kevin.tian@intel.com> Reported-by: Sukumar Ghorai <sukumar.ghorai@intel.com> Signed-off-by: Ashok Raj <ashok.raj@intel.com> Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com> Link: https://lore.kernel.org/r/20230209212843.1788125-1-jacob.jun.pan@linux.intel.com Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Signed-off-by: Joerg Roedel <jroedel@suse.de> Signed-off-by: Sasha Levin <sashal@kernel.org>
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 Restructured Text 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.