2
0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-21 03:33:59 +08:00
linux-next/arch/arm64/Kconfig.debug
Mark Rutland 604c8e676e arm64: enable CONFIG_SET_MODULE_RONX by default
The SET_MODULE_RONX protections are effectively the same as the
DEBUG_RODATA protections we enabled by default back in commit
57efac2f71 ("arm64: enable CONFIG_DEBUG_RODATA by default"). It
seems unusual to have one but not the other.

As evidenced by the help text, the rationale appears to be that
SET_MODULE_RONX interacts poorly with tracing and patching, but both of
these make use of the insn framework, which takes SET_MODULE_RONX into
account. Any remaining issues are bugs which should be fixed regardless
of the default state of the option.

This patch enables DEBUG_SET_MODULE_RONX by default, and replaces the
help text with a new wording derived from the DEBUG_RODATA help text,
which better describes the functionality. Previously, the DEBUG_RODATA
entry was inconsistently indented with spaces, which are replaced with
tabs as with the other Kconfig entries.

Additionally, the wording of recommended defaults is made consistent for
all options. These are placed in a new paragraph, unquoted, as a full
sentence (with a period/full stop) as this appears to be the most common
form per $(git grep 'in doubt').

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Laura Abbott <labbott@fedoraproject.org>
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-31 14:23:29 +01:00

78 lines
2.6 KiB
Plaintext

menu "Kernel hacking"
source "lib/Kconfig.debug"
config ARM64_PTDUMP
bool "Export kernel pagetable layout to userspace via debugfs"
depends on DEBUG_KERNEL
select DEBUG_FS
help
Say Y here if you want to show the kernel pagetable layout in a
debugfs file. This information is only useful for kernel developers
who are working in architecture specific areas of the kernel.
It is probably not a good idea to enable this feature in a production
kernel.
If in doubt, say N.
config PID_IN_CONTEXTIDR
bool "Write the current PID to the CONTEXTIDR register"
help
Enabling this option causes the kernel to write the current PID to
the CONTEXTIDR register, at the expense of some additional
instructions during context switch. Say Y here only if you are
planning to use hardware trace tools with this kernel.
config ARM64_RANDOMIZE_TEXT_OFFSET
bool "Randomize TEXT_OFFSET at build time"
help
Say Y here if you want the image load offset (AKA TEXT_OFFSET)
of the kernel to be randomized at build-time. When selected,
this option will cause TEXT_OFFSET to be randomized upon any
build of the kernel, and the offset will be reflected in the
text_offset field of the resulting Image. This can be used to
fuzz-test bootloaders which respect text_offset.
This option is intended for bootloader and/or kernel testing
only. Bootloaders must make no assumptions regarding the value
of TEXT_OFFSET and platforms must not require a specific
value.
config DEBUG_SET_MODULE_RONX
bool "Set loadable kernel module data as NX and text as RO"
depends on MODULES
default y
help
Is this is set, kernel module text and rodata will be made read-only.
This is to help catch accidental or malicious attempts to change the
kernel's executable code.
If in doubt, say Y.
config DEBUG_RODATA
bool "Make kernel text and rodata read-only"
default y
help
If this is set, kernel text and rodata will be made read-only. This
is to help catch accidental or malicious attempts to change the
kernel's executable code.
If in doubt, say Y.
config DEBUG_ALIGN_RODATA
depends on DEBUG_RODATA
bool "Align linker sections up to SECTION_SIZE"
help
If this option is enabled, sections that may potentially be marked as
read only or non-executable will be aligned up to the section size of
the kernel. This prevents sections from being split into pages and
avoids a potential TLB penalty. The downside is an increase in
alignment and potentially wasted space. Turn on this option if
performance is more important than memory pressure.
If in doubt, say N.
source "drivers/hwtracing/coresight/Kconfig"
endmenu