mainlining shenanigans
81b654c273
The cpu_has_feature() mechanism has an optimisation where at build time we construct a mask of the CPU feature bits that will always be true for the given .config, based on the platform/bitness/etc. that we are building for. That is incompatible with DT CPU features, where the set of CPU features is dependent on feature flags that are given to us by firmware. The result is that some feature bits can not be *disabled* by DT CPU features. Or more accurately, they can be disabled but they will still appear in the ALWAYS mask, meaning cpu_has_feature() will always return true for them. In the past this hasn't really been a problem because on Book3S 64 (where we support DT CPU features), the set of ALWAYS bits has been very small. That was because we always built for POWER4 and later, meaning the set of common bits was small. The only bit that could be cleared by DT CPU features that was also in the ALWAYS mask was CPU_FTR_NODSISRALIGN, and that was only used in the alignment handler to create a fake DSISR. That code was itself deleted in |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .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.
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.