[deliverable/linux.git] / arch / arm64 / Kconfig.debug

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_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
Commit	Line	Data
8c2c3df3 CM	1	menu "Kernel hacking"
	2
	3	source "lib/Kconfig.debug"
	4
c9465b4e LA	5	config ARM64_PTDUMP
	6	bool "Export kernel pagetable layout to userspace via debugfs"
	7	depends on DEBUG_KERNEL
	8	select DEBUG_FS
	9	help
	10	Say Y here if you want to show the kernel pagetable layout in a
	11	debugfs file. This information is only useful for kernel developers
	12	who are working in architecture specific areas of the kernel.
	13	It is probably not a good idea to enable this feature in a production
	14	kernel.
604c8e67 MR	15
604c8e67 MR	16	If in doubt, say N.
c9465b4e	17
ec45d1cf WD	18	config PID_IN_CONTEXTIDR
	19	bool "Write the current PID to the CONTEXTIDR register"
	20	help
	21	Enabling this option causes the kernel to write the current PID to
	22	the CONTEXTIDR register, at the expense of some additional
	23	instructions during context switch. Say Y here only if you are
	24	planning to use hardware trace tools with this kernel.
	25
da57a369 MR	26	config ARM64_RANDOMIZE_TEXT_OFFSET
	27	bool "Randomize TEXT_OFFSET at build time"
	28	help
	29	Say Y here if you want the image load offset (AKA TEXT_OFFSET)
	30	of the kernel to be randomized at build-time. When selected,
	31	this option will cause TEXT_OFFSET to be randomized upon any
	32	build of the kernel, and the offset will be reflected in the
	33	text_offset field of the resulting Image. This can be used to
	34	fuzz-test bootloaders which respect text_offset.
	35
	36	This option is intended for bootloader and/or kernel testing
	37	only. Bootloaders must make no assumptions regarding the value
	38	of TEXT_OFFSET and platforms must not require a specific
	39	value.
	40
11d91a77	41	config DEBUG_SET_MODULE_RONX
604c8e67 MR	42	bool "Set loadable kernel module data as NX and text as RO"
	43	depends on MODULES
	44	default y
	45	help
	46	Is this is set, kernel module text and rodata will be made read-only.
	47	This is to help catch accidental or malicious attempts to change the
	48	kernel's executable code.
	49
	50	If in doubt, say Y.
11d91a77	51
da141706	52	config DEBUG_ALIGN_RODATA
97740051	53	depends on DEBUG_RODATA
da141706 LA	54	bool "Align linker sections up to SECTION_SIZE"
	55	help
	56	If this option is enabled, sections that may potentially be marked as
	57	read only or non-executable will be aligned up to the section size of
	58	the kernel. This prevents sections from being split into pages and
	59	avoids a potential TLB penalty. The downside is an increase in
	60	alignment and potentially wasted space. Turn on this option if
	61	performance is more important than memory pressure.
	62
604c8e67	63	If in doubt, say N.
da141706	64
01081f5a	65	source "drivers/hwtracing/coresight/Kconfig"
3288731e	66
8c2c3df3	67	endmenu