mainlining shenanigans
39b3b3c9ca
We don't currently support IOMMUs with a page granule larger than the system page size. The IOVA allocator has a BUG_ON() in this case, and VFIO has a WARN_ON(). Removing these obstacles ranges doesn't seem possible without major changes to the DMA API and VFIO. Some callers of iommu_map(), for example, want to map multiple page-aligned regions adjacent to each others for scatter-gather purposes. Even in simple DMA API uses, a call to dma_map_page() would let the endpoint access neighbouring memory. And VFIO users cannot ensure that their virtual address buffer is physically contiguous at the IOMMU granule. Rather than triggering the IOVA BUG_ON() on mismatched page sizes, abort the vdomain finalise() with an error message. We could simply abort the viommu probe(), but an upcoming extension to virtio-iommu will allow setting different page masks for each endpoint. Reported-by: Bharat Bhushan <bbhushan2@marvell.com> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> Reviewed-by: Bharat Bhushan <bbhushan2@marvell.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Reviewed-by: Robin Murphy <robin.murphy@arm.com> Link: https://lore.kernel.org/r/20200326093558.2641019-4-jean-philippe@linaro.org Signed-off-by: Joerg Roedel <jroedel@suse.de> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.