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.
Ard Biesheuvel
authored
The ACPI PRM address space handler calls efi_call_virt_pointer() to execute PRM firmware code, but doing so is only permitted when the EFI runtime environment is available. Otherwise, such calls are guaranteed to result in a crash, and must therefore be avoided. Given that the EFI runtime services may become unavailable after a crash occurring in the firmware, we need to check this each time the PRM address space handler is invoked. If the EFI runtime services were not available at registration time to being with, don't install the address space handler at all. Fixes: cefc7ca4 ("ACPI: PRM: implement OperationRegion handler for the PlatformRtMechanism subtype") Signed-off-by:Ard Biesheuvel <ardb@kernel.org> Cc: All applicable <stable@vger.kernel.org> Signed-off-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com>