42c5a3b04b
The arm64_cpu_capabilities::cpu_enable callbacks are intended for cpu-local feature enablement (e.g. poking system registers). These get called for each online CPU when boot/system cpucaps get finalized and enabled, and get called whenever a CPU is subsequently onlined. For KPTI with the ARM64_UNMAP_KERNEL_AT_EL0 cpucap, we use the kpti_install_ng_mappings() function as the cpu_enable callback. This does a mixture of cpu-local configuration (setting VBAR_EL1 to the appropriate trampoline vectors) and some global configuration (rewriting the swapper page tables to sue non-glboal mappings) that must happen at most once. This patch splits kpti_install_ng_mappings() into a cpu-local cpu_enable_kpti() initialization function and a system-wide kpti_install_ng_mappings() function. The cpu_enable_kpti() function is responsible for selecting the necessary cpu-local vectors each time a CPU is onlined, and the kpti_install_ng_mappings() function performs the one-time rewrite of the translation tables too use non-global mappings. Splitting the two makes the code a bit easier to follow and also allows the page table rewriting code to be marked as __init such that it can be freed after use. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| 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.