b1a1347912
When two devices with same SID are getting probed concurrently through iommu_probe_device(), the iommu_group sometimes is getting allocated more than once as call to arm_smmu_device_group() is not protected for concurrency. Furthermore, it leads to each device holding a different iommu_group and domain pointer, separate IOVA space and only one of the devices' domain is used for translations from IOMMU. This causes accesses from other device to fault or see incorrect translations. Fix this by protecting iommu_group allocation from concurrency in arm_smmu_device_group(). Signed-off-by: Krishna Reddy <vdumpa@nvidia.com> Signed-off-by: Ashish Mhetre <amhetre@nvidia.com> Link: https://lore.kernel.org/r/1628570641-9127-3-git-send-email-amhetre@nvidia.com Signed-off-by: Will Deacon <will@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.