bd05220c7b
IA-64 is special and treats pgd_offset_k() differently to pgd_offset(),
using different formulae to calculate the indices into the kernel and user
PGDs. The index into the user PGDs takes into account the region number,
but the index into the kernel (init_mm) PGD always assumes a predefined
kernel region number. Commit 974b9b2c68f3 ("mm: consolidate pte_index() and
pte_offset_*() definitions") made IA-64 use a generic pgd_offset_k() which
incorrectly used pgd_index() for kernel page tables. As a result, the
index into the kernel PGD was going out of bounds and the kernel hung
during early boot.
Allow overrides of pgd_offset_k() and override it on IA-64 with the old
implementation that will correctly index the kernel PGD.
Fixes: 974b9b2c68f3 ("mm: consolidate pte_index() and pte_offset_*() definitions")
Reported-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Signed-off-by: Jessica Clarke <jrtc27@jrtc27.com>
Tested-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.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.