This fixes a problem reported by Sean MacLennan where loading any
module would cause an oops. We weren't marking the pages containing
the module text as having hardware execute permission, due to a bug
introduced in commit 8d1cf34e ("powerpc/mm: Tweak PTE bit combination
definitions"), hence trying to execute the module text caused an
exception on processors that support hardware execute permission.
This adds _PAGE_HWEXEC to the definitions of PAGE_KERNEL_X and
PAGE_KERNEL_ROX to fix this problem.
Reported-by: Sean MacLennan <smaclennan@pikatech.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that they are almost identical, we can merge some of the definitions
related to the PTE format into common files.
This creates a new pte-common.h which is included by both 32 and 64-bit
right after the CPU specific pte-*.h file, and which defines some
bits to "default" values if they haven't been defined already, and
then provides a generic definition of most of the bit combinations
based on these and exposed to the rest of the kernel.
I also moved to the common pgtable.h most of the "small" accessors to the
PTE bits and modification helpers (pte_mk*). The actual accessors remain
in their separate files.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
