c4c8a7643e
This improves the handling of transparent huge pages in the radix hypervisor page fault handler. Previously, if a small page is faulted in to a 2MB region of guest physical space, that means that there is a page table pointer at the PMD level, which could never be replaced by a leaf (2MB) PMD entry. This adds the code to clear the PMD, invlidate the page walk cache and free the page table page in this situation, so that the leaf PMD entry can be created. This also adds code to check whether a PMD or PTE being inserted is the same as is already there (because of a race with another CPU that faulted on the same page) and if so, we don't replace the existing entry, meaning that we don't invalidate the PTE or PMD and do a TLB invalidation. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. 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.