| 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 |
| 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" |
| depends on AEABI && EXPERIMENTAL |
| 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 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 DEBUG_ERRORS |
| bool "Verbose kernel error messages" |
| depends on DEBUG_KERNEL |
| help |
| This option controls verbose debugging information which can be |
| printed when the kernel detects an internal error. This debugging |
| information is useful to kernel hackers when tracking down problems, |
| but mostly meaningless to other people. It's safe to say Y unless |
| you are concerned with the code size or don't want to see these |
| messages. |
| |
| config DEBUG_STACK_USAGE |
| bool "Enable stack utilization instrumentation" |
| depends on DEBUG_KERNEL |
| help |
| Enables the display of the minimum amount of free stack which each |
| task has ever had available in the sysrq-T output. |
| |
| # These options are only for real kernel hackers who want to get their hands dirty. |
| config DEBUG_LL |
| bool "Kernel low-level debugging functions" |
| 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. |
| |
| 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 DEBUG_ICEDCC |
| bool "Kernel low-level debugging via EmbeddedICE DCC channel" |
| depends on DEBUG_LL |
| 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. |
| |
| It does include a timeout to ensure that the system does not |
| totally freeze when there is nothing connected to read. |
| |
| config OC_ETM |
| bool "On-chip ETM and ETB" |
| select 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 DEBUG_DC21285_PORT |
| bool "Kernel low-level debugging messages via footbridge serial port" |
| depends on DEBUG_LL && FOOTBRIDGE |
| help |
| Say Y here if you want the debug print routines to direct their |
| output to the serial port in the DC21285 (Footbridge). Saying N |
| will cause the debug messages to appear on the first 16550 |
| serial port. |
| |
| config DEBUG_CLPS711X_UART2 |
| bool "Kernel low-level debugging messages via UART2" |
| depends on DEBUG_LL && 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. Saying N will |
| cause the debug messages to appear on the first serial port. |
| |
| config DEBUG_S3C_UART |
| depends on PLAT_SAMSUNG |
| int "S3C UART to use for low-level debug" |
| default "0" |
| help |
| Choice for UART for kernel low-level using S3C UARTS, |
| should be between zero and two. 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. |
| |
| endmenu |