594bef7931
Right now, PGD caching requires a complicated dance of first computing the MMU role and passing it to __kvm_mmu_new_pgd(), and then separately calling kvm_init_mmu(). Part of this is due to kvm_mmu_free_roots using mmu->root_level and mmu->shadow_root_level to distinguish whether the page table uses a single root or 4 PAE roots. Because kvm_init_mmu() can overwrite mmu->root_level, kvm_mmu_free_roots() must be called before kvm_init_mmu(). However, even after kvm_init_mmu() there is a way to detect whether the page table may hold PAE roots, as root.hpa isn't backed by a shadow when it points at PAE roots. Using this method results in simpler code, and is one less obstacle in moving all calls to __kvm_mmu_new_pgd() after the MMU has been initialized. Signed-off-by: Paolo Bonzini <pbonzini@redhat.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.