menu "Kernel hacking" source "lib/Kconfig.debug" # RMK wants arm kernels compiled with frame pointers so hardwire this to y. # 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 default y help If you say N here, the resulting kernel will be slightly smaller and faster. However, when a problem occurs with the kernel, the information that is reported is severely limited. Most people should say Y here. 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. It does include a timeout to ensure that the system does not totally freeze when there is nothing connected to read. 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_PORT depends on DEBUG_LL && PLAT_S3C bool "Kernel low-level debugging messages via S3C UART" help Say Y here if you want debug print routines to go to one of the S3C internal UARTs. The chosen UART must have been configured before it is used. config DEBUG_S3C_UART depends on PLAT_S3C 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