android_kernel_samsung_msm8976/arch/arm/Kconfig.debug
Prasad Sodagudi 8ac0074944 arm: Add support for KERNEL_TEXT_RDONLY
When using FORCE_PAGES to allocate the kernel memory into pages,
provide an option to mark the the kernel text section as read only.
Since the kernel text pages are always mapped in the kernel, anyone
can write to the page if they have the address.
Enable this option to mark the kernel text pages as read only to
trigger a fault if any code attempts to write to a page that is
part of the kernel text section.

Change-Id: I27de98e2e82cf6dfe9370695239e1fae26ad0e97
Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
2014-11-25 21:02:03 +05:30

725 lines
22 KiB
Text

menu "Kernel hacking"
source "lib/Kconfig.debug"
config ARM_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 STRICT_DEVMEM
bool "Filter access to /dev/mem"
depends on MMU
---help---
If this option is disabled, you allow userspace (root) access to all
of memory, including kernel and userspace memory. Accidental
access to this is obviously disastrous, but specific access can
be used by people debugging the kernel.
If this option is switched on, the /dev/mem file only allows
userspace access to memory mapped peripherals.
If in doubt, say Y.
# RMK wants arm kernels compiled with frame pointers or stack unwinding.
# If you know what you are doing and are willing to live without stack
# traces, you can get a slightly smaller kernel by setting this option to
# n, but then RMK will have to kill you ;).
config FRAME_POINTER
bool
depends on !THUMB2_KERNEL
default y if !ARM_UNWIND || FUNCTION_GRAPH_TRACER
help
If you say N here, the resulting kernel will be slightly smaller and
faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled,
when a problem occurs with the kernel, the information that is
reported is severely limited.
config ARM_UNWIND
bool "Enable stack unwinding support (EXPERIMENTAL)"
depends on AEABI
default y
help
This option enables stack unwinding support in the kernel
using the information automatically generated by the
compiler. The resulting kernel image is slightly bigger but
the performance is not affected. Currently, this feature
only works with EABI compilers. If unsure say Y.
config OLD_MCOUNT
bool
depends on FUNCTION_TRACER && FRAME_POINTER
default y
config DEBUG_USER
bool "Verbose user fault messages"
help
When a user program crashes due to an exception, the kernel can
print a brief message explaining what the problem was. This is
sometimes helpful for debugging but serves no purpose on a
production system. Most people should say N here.
In addition, you need to pass user_debug=N on the kernel command
line to enable this feature. N consists of the sum of:
1 - undefined instruction events
2 - system calls
4 - invalid data aborts
8 - SIGSEGV faults
16 - SIGBUS faults
config FORCE_PAGES
bool "Force lowmem to be mapped with 4K pages"
help
There are some advanced debug features that can only be done when
memory is mapped with pages instead of sections. Enable this option
to always map lowmem pages with pages. This may have a performance
cost due to increased TLB pressure.
If unsure say N.
config FREE_PAGES_RDONLY
bool "Set pages as read only while on the buddy list"
select FORCE_PAGES
select DEBUG_PAGEALLOC
help
Pages are always mapped in the kernel. This means that anyone
can write to the page if they have the address. Enable this option
to mark pages as read only to trigger a fault if any code attempts
to write to a page on the buddy list. This may have a performance
impact.
If unsure, say N.
config KERNEL_TEXT_RDONLY
bool "Set kernel text section pages as read only"
depends on FREE_PAGES_RDONLY
help
The kernel text pages are always mapped in the kernel.
This means that anyone can write to the page if they have
the address. Enable this option to mark the kernel text pages
as read only to trigger a fault if any code attempts to write
to a page part of the kernel text section. This may have a
performance impact.
If unsure, say N.
# These options are only for real kernel hackers who want to get their hands dirty.
config DEBUG_LL
bool "Kernel low-level debugging functions (read help!)"
depends on DEBUG_KERNEL
help
Say Y here to include definitions of printascii, printch, printhex
in the kernel. This is helpful if you are debugging code that
executes before the console is initialized.
Note that selecting this option will limit the kernel to a single
UART definition, as specified below. Attempting to boot the kernel
image on a different platform *will not work*, so this option should
not be enabled for kernels that are intended to be portable.
choice
prompt "Kernel low-level debugging port"
depends on DEBUG_LL
config AT91_DEBUG_LL_DBGU0
bool "Kernel low-level debugging on rm9200, 9260/9g20, 9261/9g10 and 9rl"
depends on HAVE_AT91_DBGU0
config AT91_DEBUG_LL_DBGU1
bool "Kernel low-level debugging on 9263 and 9g45"
depends on HAVE_AT91_DBGU1
config DEBUG_BCM2835
bool "Kernel low-level debugging on BCM2835 PL011 UART"
depends on ARCH_BCM2835
config DEBUG_CLPS711X_UART1
bool "Kernel low-level debugging messages via UART1"
depends on ARCH_CLPS711X
help
Say Y here if you want the debug print routines to direct
their output to the first serial port on these devices.
config DEBUG_CLPS711X_UART2
bool "Kernel low-level debugging messages via UART2"
depends on ARCH_CLPS711X
help
Say Y here if you want the debug print routines to direct
their output to the second serial port on these devices.
config DEBUG_CNS3XXX
bool "Kernel Kernel low-level debugging on Cavium Networks CNS3xxx"
depends on ARCH_CNS3XXX
help
Say Y here if you want the debug print routines to direct
their output to the CNS3xxx UART0.
config DEBUG_DAVINCI_DA8XX_UART1
bool "Kernel low-level debugging on DaVinci DA8XX using UART1"
depends on ARCH_DAVINCI_DA8XX
help
Say Y here if you want the debug print routines to direct
their output to UART1 serial port on DaVinci DA8XX devices.
config DEBUG_DAVINCI_DA8XX_UART2
bool "Kernel low-level debugging on DaVinci DA8XX using UART2"
depends on ARCH_DAVINCI_DA8XX
help
Say Y here if you want the debug print routines to direct
their output to UART2 serial port on DaVinci DA8XX devices.
config DEBUG_DAVINCI_DMx_UART0
bool "Kernel low-level debugging on DaVinci DMx using UART0"
depends on ARCH_DAVINCI_DMx
help
Say Y here if you want the debug print routines to direct
their output to UART0 serial port on DaVinci DMx devices.
config DEBUG_DAVINCI_TNETV107X_UART1
bool "Kernel low-level debugging on DaVinci TNETV107x using UART1"
depends on ARCH_DAVINCI_TNETV107X
help
Say Y here if you want the debug print routines to direct
their output to UART1 serial port on DaVinci TNETV107X
devices.
config DEBUG_ZYNQ_UART0
bool "Kernel low-level debugging on Xilinx Zynq using UART0"
depends on ARCH_ZYNQ
help
Say Y here if you want the debug print routines to direct
their output to UART0 on the Zynq platform.
config DEBUG_ZYNQ_UART1
bool "Kernel low-level debugging on Xilinx Zynq using UART1"
depends on ARCH_ZYNQ
help
Say Y here if you want the debug print routines to direct
their output to UART1 on the Zynq platform.
If you have a ZC702 board and want early boot messages to
appear on the USB serial adaptor, select this option.
config DEBUG_DC21285_PORT
bool "Kernel low-level debugging messages via footbridge serial port"
depends on FOOTBRIDGE
help
Say Y here if you want the debug print routines to direct
their output to the serial port in the DC21285 (Footbridge).
config DEBUG_FOOTBRIDGE_COM1
bool "Kernel low-level debugging messages via footbridge 8250 at PCI COM1"
depends on FOOTBRIDGE
help
Say Y here if you want the debug print routines to direct
their output to the 8250 at PCI COM1.
config DEBUG_HIGHBANK_UART
bool "Kernel low-level debugging messages via Highbank UART"
depends on ARCH_HIGHBANK
help
Say Y here if you want the debug print routines to direct
their output to the UART on Highbank based devices.
config DEBUG_IMX1_UART
bool "i.MX1 Debug UART"
depends on SOC_IMX1
help
Say Y here if you want kernel low-level debugging support
on i.MX1.
config DEBUG_IMX23_UART
bool "i.MX23 Debug UART"
depends on SOC_IMX23
help
Say Y here if you want kernel low-level debugging support
on i.MX23.
config DEBUG_IMX25_UART
bool "i.MX25 Debug UART"
depends on SOC_IMX25
help
Say Y here if you want kernel low-level debugging support
on i.MX25.
config DEBUG_IMX21_IMX27_UART
bool "i.MX21 and i.MX27 Debug UART"
depends on SOC_IMX21 || SOC_IMX27
help
Say Y here if you want kernel low-level debugging support
on i.MX21 or i.MX27.
config DEBUG_IMX28_UART
bool "i.MX28 Debug UART"
depends on SOC_IMX28
help
Say Y here if you want kernel low-level debugging support
on i.MX28.
config DEBUG_IMX31_UART
bool "i.MX31 Debug UART"
depends on SOC_IMX31
help
Say Y here if you want kernel low-level debugging support
on i.MX31.
config DEBUG_IMX35_UART
bool "i.MX35 Debug UART"
depends on SOC_IMX35
help
Say Y here if you want kernel low-level debugging support
on i.MX35.
config DEBUG_IMX51_UART
bool "i.MX51 Debug UART"
depends on SOC_IMX51
help
Say Y here if you want kernel low-level debugging support
on i.MX51.
config DEBUG_IMX53_UART
bool "i.MX53 Debug UART"
depends on SOC_IMX53
help
Say Y here if you want kernel low-level debugging support
on i.MX53.
config DEBUG_IMX6Q_UART
bool "i.MX6Q/DL Debug UART"
depends on SOC_IMX6Q
help
Say Y here if you want kernel low-level debugging support
on i.MX6Q/DL.
config DEBUG_MMP_UART2
bool "Kernel low-level debugging message via MMP UART2"
depends on ARCH_MMP
help
Say Y here if you want kernel low-level debugging support
on MMP UART2.
config DEBUG_MMP_UART3
bool "Kernel low-level debugging message via MMP UART3"
depends on ARCH_MMP
help
Say Y here if you want kernel low-level debugging support
on MMP UART3.
config DEBUG_MVEBU_UART
bool "Kernel low-level debugging messages via MVEBU UART"
depends on ARCH_MVEBU
help
Say Y here if you want kernel low-level debugging support
on MVEBU based platforms.
config DEBUG_NOMADIK_UART
bool "Kernel low-level debugging messages via NOMADIK UART"
depends on ARCH_NOMADIK
help
Say Y here if you want kernel low-level debugging support
on NOMADIK based platforms.
config DEBUG_OMAP2PLUS_UART
bool "Kernel low-level debugging messages via OMAP2PLUS UART"
depends on ARCH_OMAP2PLUS
help
Say Y here if you want kernel low-level debugging support
on OMAP2PLUS based platforms.
config DEBUG_PICOXCELL_UART
depends on ARCH_PICOXCELL
bool "Use PicoXcell UART for low-level debug"
help
Say Y here if you want kernel low-level debugging support
on PicoXcell based platforms.
config DEBUG_PXA_UART1
depends on ARCH_PXA
bool "Use PXA UART1 for low-level debug"
help
Say Y here if you want kernel low-level debugging support
on PXA UART1.
config DEBUG_REALVIEW_STD_PORT
bool "RealView Default UART"
depends on ARCH_REALVIEW
help
Say Y here if you want the debug print routines to direct
their output to the serial port on RealView EB, PB11MP, PBA8
and PBX platforms.
config DEBUG_REALVIEW_PB1176_PORT
bool "RealView PB1176 UART"
depends on MACH_REALVIEW_PB1176
help
Say Y here if you want the debug print routines to direct
their output to the standard serial port on the RealView
PB1176 platform.
config DEBUG_S3C_UART0
depends on PLAT_SAMSUNG
select DEBUG_EXYNOS_UART if ARCH_EXYNOS
bool "Use S3C UART 0 for low-level debug"
help
Say Y here if you want the debug print routines to direct
their output to UART 0. The port must have been initialised
by the boot-loader before use.
The uncompressor code port configuration is now handled
by CONFIG_S3C_LOWLEVEL_UART_PORT.
config DEBUG_S3C_UART1
depends on PLAT_SAMSUNG
select DEBUG_EXYNOS_UART if ARCH_EXYNOS
bool "Use S3C UART 1 for low-level debug"
help
Say Y here if you want the debug print routines to direct
their output to UART 1. The port must have been initialised
by the boot-loader before use.
The uncompressor code port configuration is now handled
by CONFIG_S3C_LOWLEVEL_UART_PORT.
config DEBUG_S3C_UART2
depends on PLAT_SAMSUNG
select DEBUG_EXYNOS_UART if ARCH_EXYNOS
bool "Use S3C UART 2 for low-level debug"
help
Say Y here if you want the debug print routines to direct
their output to UART 2. The port must have been initialised
by the boot-loader before use.
The uncompressor code port configuration is now handled
by CONFIG_S3C_LOWLEVEL_UART_PORT.
config DEBUG_S3C_UART3
depends on PLAT_SAMSUNG && ARCH_EXYNOS
select DEBUG_EXYNOS_UART
bool "Use S3C UART 3 for low-level debug"
help
Say Y here if you want the debug print routines to direct
their output to UART 3. The port must have been initialised
by the boot-loader before use.
The uncompressor code port configuration is now handled
by CONFIG_S3C_LOWLEVEL_UART_PORT.
config DEBUG_SOCFPGA_UART
depends on ARCH_SOCFPGA
bool "Use SOCFPGA UART for low-level debug"
help
Say Y here if you want kernel low-level debugging support
on SOCFPGA based platforms.
config DEBUG_SUNXI_UART0
bool "Kernel low-level debugging messages via sunXi UART0"
depends on ARCH_SUNXI
help
Say Y here if you want kernel low-level debugging support
on Allwinner A1X based platforms on the UART0.
config DEBUG_SUNXI_UART1
bool "Kernel low-level debugging messages via sunXi UART1"
depends on ARCH_SUNXI
help
Say Y here if you want kernel low-level debugging support
on Allwinner A1X based platforms on the UART1.
config DEBUG_TEGRA_UART
depends on ARCH_TEGRA
bool "Use Tegra UART for low-level debug"
help
Say Y here if you want kernel low-level debugging support
on Tegra based platforms.
config DEBUG_SIRFPRIMA2_UART1
bool "Kernel low-level debugging messages via SiRFprimaII UART1"
depends on ARCH_PRIMA2
help
Say Y here if you want the debug print routines to direct
their output to the uart1 port on SiRFprimaII devices.
config DEBUG_SIRFMARCO_UART1
bool "Kernel low-level debugging messages via SiRFmarco UART1"
depends on ARCH_MARCO
help
Say Y here if you want the debug print routines to direct
their output to the uart1 port on SiRFmarco devices.
config DEBUG_UX500_UART
depends on ARCH_U8500
bool "Use Ux500 UART for low-level debug"
help
Say Y here if you want kernel low-level debugging support
on Ux500 based platforms.
config DEBUG_VEXPRESS_UART0_DETECT
bool "Autodetect UART0 on Versatile Express Cortex-A core tiles"
depends on ARCH_VEXPRESS && CPU_CP15_MMU
help
This option enables a simple heuristic which tries to determine
the motherboard's memory map variant (original or RS1) and then
choose the relevant UART0 base address.
Note that this will only work with standard A-class core tiles,
and may fail with non-standard SMM or custom software models.
config DEBUG_VEXPRESS_UART0_CA9
bool "Use PL011 UART0 at 0x10009000 (V2P-CA9 core tile)"
depends on ARCH_VEXPRESS
help
This option selects UART0 at 0x10009000. Except for custom models,
this applies only to the V2P-CA9 tile.
config DEBUG_VEXPRESS_UART0_RS1
bool "Use PL011 UART0 at 0x1c090000 (RS1 complaint tiles)"
depends on ARCH_VEXPRESS
help
This option selects UART0 at 0x1c090000. This applies to most
of the tiles using the RS1 memory map, including all new A-class
core tiles, FPGA-based SMMs and software models.
config DEBUG_VT8500_UART0
bool "Use UART0 on VIA/Wondermedia SoCs"
depends on ARCH_VT8500
help
This option selects UART0 on VIA/Wondermedia System-on-a-chip
devices, including VT8500, WM8505, WM8650 and WM8850.
config DEBUG_LL_UART_NONE
bool "No low-level debugging UART"
depends on !ARCH_MULTIPLATFORM
help
Say Y here if your platform doesn't provide a UART option
below. This relies on your platform choosing the right UART
definition internally in order for low-level debugging to
work.
config DEBUG_ICEDCC
bool "Kernel low-level debugging via EmbeddedICE DCC channel"
help
Say Y here if you want the debug print routines to direct
their output to the EmbeddedICE macrocell's DCC channel using
co-processor 14. This is known to work on the ARM9 style ICE
channel and on the XScale with the PEEDI.
Note that the system will appear to hang during boot if there
is nothing connected to read from the DCC.
config DEBUG_SEMIHOSTING
bool "Kernel low-level debug output via semihosting I/O"
help
Semihosting enables code running on an ARM target to use
the I/O facilities on a host debugger/emulator through a
simple SVC call. The host debugger or emulator must have
semihosting enabled for the special svc call to be trapped
otherwise the kernel will crash.
This is known to work with OpenOCD, as well as
ARM's Fast Models, or any other controlling environment
that implements semihosting.
For more details about semihosting, please see
chapter 8 of DUI0203I_rvct_developer_guide.pdf from ARM Ltd.
endchoice
config DEBUG_EXYNOS_UART
bool
config DEBUG_IMX_UART_PORT
int "i.MX Debug UART Port Selection" if DEBUG_IMX1_UART || \
DEBUG_IMX25_UART || \
DEBUG_IMX21_IMX27_UART || \
DEBUG_IMX31_UART || \
DEBUG_IMX35_UART || \
DEBUG_IMX51_UART || \
DEBUG_IMX53_UART || \
DEBUG_IMX6Q_UART
default 1
depends on ARCH_MXC
help
Choose UART port on which kernel low-level debug messages
should be output.
choice
prompt "Low-level debug console UART"
depends on DEBUG_OMAP2PLUS_UART
config DEBUG_OMAP2UART1
bool "OMAP2/3/4 UART1 (omap2/3 sdp boards and some omap3 boards)"
help
This covers at least h4, 2430sdp, 3430sdp, 3630sdp,
omap3 torpedo and 3530 lv som.
config DEBUG_OMAP2UART2
bool "OMAP2/3/4 UART2"
config DEBUG_OMAP2UART3
bool "OMAP2 UART3 (n8x0)"
config DEBUG_OMAP3UART3
bool "OMAP3 UART3 (most omap3 boards)"
help
This covers at least cm_t3x, beagle, crane, devkit8000,
igep00x0, ldp, n900, n9(50), pandora, overo, touchbook,
and 3517evm.
config DEBUG_OMAP4UART3
bool "OMAP4/5 UART3 (omap4 blaze, panda, omap5 sevm)"
config DEBUG_OMAP3UART4
bool "OMAP36XX UART4"
config DEBUG_OMAP4UART4
bool "OMAP4/5 UART4"
config DEBUG_TI81XXUART1
bool "TI81XX UART1 (ti8148evm)"
config DEBUG_TI81XXUART2
bool "TI81XX UART2"
config DEBUG_TI81XXUART3
bool "TI81XX UART3 (ti8168evm)"
config DEBUG_AM33XXUART1
bool "AM33XX UART1"
config DEBUG_ZOOM_UART
bool "Zoom2/3 UART"
endchoice
choice
prompt "Low-level debug console UART"
depends on DEBUG_LL && DEBUG_TEGRA_UART
config TEGRA_DEBUG_UART_AUTO_ODMDATA
bool "Via ODMDATA"
help
Automatically determines which UART to use for low-level debug based
on the ODMDATA value. This value is part of the BCT, and is written
to the boot memory device using nvflash, or other flashing tool.
When bits 19:18 are 3, then bits 17:15 indicate which UART to use;
0/1/2/3/4 are UART A/B/C/D/E.
config TEGRA_DEBUG_UARTA
bool "UART A"
config TEGRA_DEBUG_UARTB
bool "UART B"
config TEGRA_DEBUG_UARTC
bool "UART C"
config TEGRA_DEBUG_UARTD
bool "UART D"
config TEGRA_DEBUG_UARTE
bool "UART E"
endchoice
config DEBUG_LL_INCLUDE
string
default "debug/bcm2835.S" if DEBUG_BCM2835
default "debug/cns3xxx.S" if DEBUG_CNS3XXX
default "debug/exynos.S" if DEBUG_EXYNOS_UART
default "debug/highbank.S" if DEBUG_HIGHBANK_UART
default "debug/icedcc.S" if DEBUG_ICEDCC
default "debug/imx.S" if DEBUG_IMX1_UART || \
DEBUG_IMX25_UART || \
DEBUG_IMX21_IMX27_UART || \
DEBUG_IMX31_UART || \
DEBUG_IMX35_UART || \
DEBUG_IMX51_UART || \
DEBUG_IMX53_UART ||\
DEBUG_IMX6Q_UART
default "debug/mvebu.S" if DEBUG_MVEBU_UART
default "debug/mxs.S" if DEBUG_IMX23_UART || DEBUG_IMX28_UART
default "debug/nomadik.S" if DEBUG_NOMADIK_UART
default "debug/omap2plus.S" if DEBUG_OMAP2PLUS_UART
default "debug/picoxcell.S" if DEBUG_PICOXCELL_UART
default "debug/pxa.S" if DEBUG_PXA_UART1 || DEBUG_MMP_UART2 || \
DEBUG_MMP_UART3
default "debug/sirf.S" if DEBUG_SIRFPRIMA2_UART1 || DEBUG_SIRFMARCO_UART1
default "debug/socfpga.S" if DEBUG_SOCFPGA_UART
default "debug/sunxi.S" if DEBUG_SUNXI_UART0 || DEBUG_SUNXI_UART1
default "debug/tegra.S" if DEBUG_TEGRA_UART
default "debug/ux500.S" if DEBUG_UX500_UART
default "debug/vexpress.S" if DEBUG_VEXPRESS_UART0_DETECT || \
DEBUG_VEXPRESS_UART0_CA9 || DEBUG_VEXPRESS_UART0_RS1
default "debug/vt8500.S" if DEBUG_VT8500_UART0
default "debug/zynq.S" if DEBUG_ZYNQ_UART0 || DEBUG_ZYNQ_UART1
default "mach/debug-macro.S"
config DEBUG_UNCOMPRESS
bool
default y if ARCH_MULTIPLATFORM && DEBUG_LL && \
!DEBUG_OMAP2PLUS_UART && \
!DEBUG_TEGRA_UART
config UNCOMPRESS_INCLUDE
string
default "debug/uncompress.h" if ARCH_MULTIPLATFORM
default "mach/uncompress.h"
config EARLY_PRINTK
bool "Early printk"
depends on DEBUG_LL
help
Say Y here if you want to have an early console using the
kernel low-level debugging functions. Add earlyprintk to your
kernel parameters to enable this console.
config EARLY_PRINTK_DIRECT
bool "Early printk direct"
depends on DEBUG_LL
help
Say Y here if you want to have an early console using the
kernel low-level debugging functions and EARLY_PRINTK is
not early enough.
config OC_ETM
bool "On-chip ETM and ETB"
depends on ARM_AMBA
help
Enables the on-chip embedded trace macrocell and embedded trace
buffer driver that will allow you to collect traces of the
kernel code.
config ARM_KPROBES_TEST
tristate "Kprobes test module"
depends on KPROBES && MODULES
help
Perform tests of kprobes API and instruction set simulation.
config PID_IN_CONTEXTIDR
bool "Write the current PID to the CONTEXTIDR register"
depends on CPU_COPY_V6
help
Enabling this option causes the kernel to write the current PID to
the PROCID field of 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 DEBUG_SET_MODULE_RONX
bool "Set loadable kernel module data as NX and text as RO"
depends on MODULES
---help---
This option helps catch unintended modifications to loadable
kernel module's text and read-only data. It also prevents execution
of module data. Such protection may interfere with run-time code
patching and dynamic kernel tracing - and they might also protect
against certain classes of kernel exploits.
If in doubt, say "N".
endmenu