[PATCH 0/7] introduce __ro_mostly_after_init section marker

From: Hoeun Ryu
Date: Sun Feb 19 2017 - 05:03:56 EST

After `__ro_after_init` marker is included in kernel, many kernel data
objects can be read-only-after-init. But there are many other places that
would be good to read-only-after-init but `__ro_after_init` can not be simply
applicable to them because they should be writable at some points, which are
during module_init/exit or dynamic de/registration for a specific subsystem.
`__ro_mostly_after_init` is basically the same to `__ro_after_init`. The
section is mapped as read-only after kernel init. The different thing is
this section is temporarily mapped as read-write during module_init/exit and
de/registration of a subsystem using set_ro_mostly_after_init_rw/ro pair.

- Tested only on arm64.

0001 patch is `__ro_mostly_after_init` itself.
0002 patch is to add set_ro_mostly_after_init_rw/ro pair using
0003 patch is to make the section read-write in module_init/exit.
0004 patch is an example for dynamic init/deinit of a subsystem.
0005 patch is an example for __ro_mostly_after_init section modified during
0006/0007 patches are fixes for arm64 kernel mapping.

Hoeun Ryu (7):
arch: add __ro_mostly_after_init section marker
init: add set_ro_mostly_after_init_rw/ro function
module: modify memory attrs for __ro_mostly_after_init during
selinux: mark __ro_mostly_after_init for selinux_hooks/selinux_nf_ops
cpu: mark ro_mostly_after_init for cpuhp_ap/bp_states
arm64: add __map_kernel_segment to accept additional vm flags
arm64: map seperately rodata sections for __ro_mostly_after_init

arch/arm64/mm/mmu.c | 44 ++++++++++++++++++++++++++++++++-------
include/asm-generic/sections.h | 1 +
include/asm-generic/vmlinux.lds.h | 10 +++++++++
include/linux/cache.h | 11 ++++++++++
include/linux/init.h | 6 ++++++
init/main.c | 24 +++++++++++++++++++++
kernel/cpu.c | 4 ++--
kernel/module.c | 10 +++++++--
security/selinux/hooks.c | 8 +++++--
9 files changed, 105 insertions(+), 13 deletions(-)