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|
menu "Kernel hacking"
source "lib/Kconfig.debug"
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
# 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_IMX6SL_UART
bool "i.MX6SL Debug UART"
depends on SOC_IMX6SL
help
Say Y here if you want kernel low-level debugging support
on i.MX6SL.
config DEBUG_KEYSTONE_UART0
bool "Kernel low-level debugging on KEYSTONE2 using UART0"
depends on ARCH_KEYSTONE
help
Say Y here if you want the debug print routines to direct
their output to UART0 serial port on KEYSTONE2 devices.
config DEBUG_KEYSTONE_UART1
bool "Kernel low-level debugging on KEYSTONE2 using UART1"
depends on ARCH_KEYSTONE
help
Say Y here if you want the debug print routines to direct
their output to UART1 serial port on KEYSTONE2 devices.
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_MSM_UART1
bool "Kernel low-level debugging messages via MSM UART1"
depends on ARCH_MSM7X00A || ARCH_MSM7X30 || ARCH_QSD8X50
help
Say Y here if you want the debug print routines to direct
their output to the first serial port on MSM devices.
config DEBUG_MSM_UART2
bool "Kernel low-level debugging messages via MSM UART2"
depends on ARCH_MSM7X00A || ARCH_MSM7X30 || ARCH_QSD8X50
help
Say Y here if you want the debug print routines to direct
their output to the second serial port on MSM devices.
config DEBUG_MSM_UART3
bool "Kernel low-level debugging messages via MSM UART3"
depends on ARCH_MSM7X00A || ARCH_MSM7X30 || ARCH_QSD8X50
help
Say Y here if you want the debug print routines to direct
their output to the third serial port on MSM devices.
config DEBUG_MSM8660_UART
bool "Kernel low-level debugging messages via MSM 8660 UART"
depends on ARCH_MSM8X60
select MSM_HAS_DEBUG_UART_HS
help
Say Y here if you want the debug print routines to direct
their output to the serial port on MSM 8660 devices.
config DEBUG_MSM8960_UART
bool "Kernel low-level debugging messages via MSM 8960 UART"
depends on ARCH_MSM8960
select MSM_HAS_DEBUG_UART_HS
help
Say Y here if you want the debug print routines to direct
their output to the serial port on MSM 8960 devices.
config DEBUG_MVEBU_UART
bool "Kernel low-level debugging messages via MVEBU UART (old bootloaders)"
depends on ARCH_MVEBU
help
Say Y here if you want kernel low-level debugging support
on MVEBU based platforms.
This option should be used with the old bootloaders
that left the internal registers mapped at
0xd0000000. As of today, this is the case on
platforms such as the Globalscale Mirabox or the
Plathome OpenBlocks AX3, when using the original
bootloader.
If the wrong DEBUG_MVEBU_UART* option is selected,
when u-boot hands over to the kernel, the system
silently crashes, with no serial output at all.
config DEBUG_MVEBU_UART_ALTERNATE
bool "Kernel low-level debugging messages via MVEBU UART (new bootloaders)"
depends on ARCH_MVEBU
help
Say Y here if you want kernel low-level debugging support
on MVEBU based platforms.
This option should be used with the new bootloaders
that remap the internal registers at 0xf1000000.
If the wrong DEBUG_MVEBU_UART* option is selected,
when u-boot hands over to the kernel, the system
silently crashes, with no serial output at all.
config DEBUG_NOMADIK_UART
bool "Kernel low-level debugging messages via NOMADIK UART"
depends on ARCH_NOMADIK
|