mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-02 18:04:38 -04:00
7f6d498ed3
Commit9abcc981de("powerpc/mm/radix: Only add X for pages overlapping kernel text") changed the linear mapping on Radix to only mark the kernel text executable. However if the kernel is run relocated, for example as a kdump kernel, then the exception vectors are split from the kernel text, ie. they remain at real address 0. We tend to get away with it, because the kernel itself will usually be below 1G, which means the 1G page at 0-1G is marked executable and everything works OK. However if the kernel is loaded above 1G, or the system has less than 1G in total (meaning we can't use a 1G page), then the exception vectors will not be marked executable and the kernel will fail to boot. Fix it by also checking if the address range overlaps the exception vectors when deciding if we should add PAGE_KERNEL_X. Fixes:9abcc981de("powerpc/mm/radix: Only add X for pages overlapping kernel text") Cc: stable@vger.kernel.org # v4.7+ Signed-off-by: Balbir Singh <bsingharora@gmail.com> [mpe: Combine with the existing check, rewrite change log] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
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.