Commit 1e0fc9d1 authored Jun 29, 2017 by Balbir Singh Committed by Michael Ellerman Jul 04, 2017

powerpc/Kconfig: Enable STRICT_KERNEL_RWX for some configs



All code that patches kernel text has been moved over to using
patch_instruction() and patch_instruction() is able to cope with the
kernel text being read only.

The linker script has been updated to ensure the read only data ends
on a large page boundary, so it and the preceding kernel text can be
marked R_X. We also have implementations of mark_rodata_ro() for Hash
and Radix MMU modes.

There are some corner-cases missing when the kernel is built
relocatable, so for now make it depend on !RELOCATABLE.

There's also a temporary workaround to depend on !HIBERNATION to avoid
a build failure, that will be removed once we've merged with the PM
tree.

Signed-off-by: Balbir Singh <bsingharora@gmail.com>
[mpe: Make it depend on !RELOCATABLE, munge change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

parent 7614ff32

arch/powerpc/Kconfig

+2 −0

Original line number	Diff line number	Diff line
		@@ -164,6 +164,8 @@ config PPC
		select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
		select HAVE_ARCH_SECCOMP_FILTER
		select HAVE_ARCH_TRACEHOOK
		select ARCH_HAS_STRICT_KERNEL_RWX if (PPC_BOOK3S_64 && !RELOCATABLE && !HIBERNATION)
		select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
		select HAVE_CBPF_JIT if !PPC64
		select HAVE_CONTEXT_TRACKING if PPC64
		select HAVE_DEBUG_KMEMLEAK

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