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Commit63bed96604("x86/startup_64: Defer assignment of 5-level paging global variables") moved assignment of 5-level global variables to later in the boot in order to avoid having to use RIP relative addressing in order to set them. However, when running with 5-level paging and SME active (mem_encrypt=on), the variables are needed as part of the page table setup needed to encrypt the kernel (using pgd_none(), p4d_offset(), etc.). Since the variables haven't been set, the page table manipulation is done as if 4-level paging is active, causing the system to crash on boot. While only a subset of the assignments that were moved need to be set early, move all of the assignments back into check_la57_support() so that these assignments aren't spread between two locations. Instead of just reverting the fix, this uses the new RIP_REL_REF() macro when assigning the variables. Fixes:63bed96604("x86/startup_64: Defer assignment of 5-level paging global variables") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/2ca419f4d0de719926fd82353f6751f717590a86.1711122067.git.thomas.lendacky@amd.com
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.