Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | menu "Kernel hacking" |
| 2 | |
| 3 | source "lib/Kconfig.debug" |
| 4 | |
Nicolas Pitre | 087aaff | 2010-09-22 18:34:36 -0400 | [diff] [blame] | 5 | config STRICT_DEVMEM |
| 6 | bool "Filter access to /dev/mem" |
| 7 | depends on MMU |
| 8 | ---help--- |
| 9 | If this option is disabled, you allow userspace (root) access to all |
| 10 | of memory, including kernel and userspace memory. Accidental |
| 11 | access to this is obviously disastrous, but specific access can |
| 12 | be used by people debugging the kernel. |
| 13 | |
| 14 | If this option is switched on, the /dev/mem file only allows |
| 15 | userspace access to memory mapped peripherals. |
| 16 | |
| 17 | If in doubt, say Y. |
| 18 | |
Catalin Marinas | adf8b37 | 2009-02-12 13:56:34 +0100 | [diff] [blame] | 19 | # RMK wants arm kernels compiled with frame pointers or stack unwinding. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | # If you know what you are doing and are willing to live without stack |
| 21 | # traces, you can get a slightly smaller kernel by setting this option to |
| 22 | # n, but then RMK will have to kill you ;). |
| 23 | config FRAME_POINTER |
| 24 | bool |
Catalin Marinas | 16c7965 | 2009-07-24 12:33:02 +0100 | [diff] [blame] | 25 | depends on !THUMB2_KERNEL |
Rabin Vincent | 0e341af | 2010-11-06 23:03:53 +0530 | [diff] [blame] | 26 | default y if !ARM_UNWIND || FUNCTION_GRAPH_TRACER |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | help |
| 28 | If you say N here, the resulting kernel will be slightly smaller and |
Catalin Marinas | adf8b37 | 2009-02-12 13:56:34 +0100 | [diff] [blame] | 29 | faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled, |
| 30 | when a problem occurs with the kernel, the information that is |
| 31 | reported is severely limited. |
| 32 | |
| 33 | config ARM_UNWIND |
Russell King | 4a50bfe | 2010-12-05 23:06:22 +0000 | [diff] [blame] | 34 | bool "Enable stack unwinding support (EXPERIMENTAL)" |
Catalin Marinas | adf8b37 | 2009-02-12 13:56:34 +0100 | [diff] [blame] | 35 | depends on AEABI && EXPERIMENTAL |
| 36 | default y |
| 37 | help |
| 38 | This option enables stack unwinding support in the kernel |
| 39 | using the information automatically generated by the |
| 40 | compiler. The resulting kernel image is slightly bigger but |
| 41 | the performance is not affected. Currently, this feature |
| 42 | only works with EABI compilers. If unsure say Y. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | |
Rabin Vincent | 09bfafa | 2010-08-10 19:32:37 +0100 | [diff] [blame] | 44 | config OLD_MCOUNT |
| 45 | bool |
| 46 | depends on FUNCTION_TRACER && FRAME_POINTER |
| 47 | default y |
| 48 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | config DEBUG_USER |
| 50 | bool "Verbose user fault messages" |
| 51 | help |
| 52 | When a user program crashes due to an exception, the kernel can |
| 53 | print a brief message explaining what the problem was. This is |
| 54 | sometimes helpful for debugging but serves no purpose on a |
| 55 | production system. Most people should say N here. |
| 56 | |
| 57 | In addition, you need to pass user_debug=N on the kernel command |
| 58 | line to enable this feature. N consists of the sum of: |
| 59 | |
| 60 | 1 - undefined instruction events |
| 61 | 2 - system calls |
| 62 | 4 - invalid data aborts |
| 63 | 8 - SIGSEGV faults |
| 64 | 16 - SIGBUS faults |
| 65 | |
Sascha Hauer | ddf4e42c | 2007-07-24 18:37:01 +0200 | [diff] [blame] | 66 | config DEBUG_STACK_USAGE |
| 67 | bool "Enable stack utilization instrumentation" |
| 68 | depends on DEBUG_KERNEL |
| 69 | help |
| 70 | Enables the display of the minimum amount of free stack which each |
| 71 | task has ever had available in the sysrq-T output. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 72 | |
| 73 | # These options are only for real kernel hackers who want to get their hands dirty. |
| 74 | config DEBUG_LL |
| 75 | bool "Kernel low-level debugging functions" |
| 76 | depends on DEBUG_KERNEL |
| 77 | help |
Russell King | 35efb60 | 2005-09-09 15:57:17 +0100 | [diff] [blame] | 78 | Say Y here to include definitions of printascii, printch, printhex |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 79 | in the kernel. This is helpful if you are debugging code that |
| 80 | executes before the console is initialized. |
| 81 | |
Catalin Marinas | 93fd03a | 2009-12-09 10:02:18 +0000 | [diff] [blame] | 82 | config EARLY_PRINTK |
| 83 | bool "Early printk" |
| 84 | depends on DEBUG_LL |
| 85 | help |
| 86 | Say Y here if you want to have an early console using the |
| 87 | kernel low-level debugging functions. Add earlyprintk to your |
| 88 | kernel parameters to enable this console. |
| 89 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 90 | config DEBUG_ICEDCC |
| 91 | bool "Kernel low-level debugging via EmbeddedICE DCC channel" |
| 92 | depends on DEBUG_LL |
| 93 | help |
| 94 | Say Y here if you want the debug print routines to direct their |
| 95 | output to the EmbeddedICE macrocell's DCC channel using |
| 96 | co-processor 14. This is known to work on the ARM9 style ICE |
Jean-Christop PLAGNIOL-VILLARD | c633c3c | 2009-02-25 04:20:40 +0100 | [diff] [blame] | 97 | channel and on the XScale with the PEEDI. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 98 | |
| 99 | It does include a timeout to ensure that the system does not |
| 100 | totally freeze when there is nothing connected to read. |
| 101 | |
Alexander Shishkin | c5d6c77 | 2009-12-01 14:00:51 +0100 | [diff] [blame] | 102 | config OC_ETM |
| 103 | bool "On-chip ETM and ETB" |
| 104 | select ARM_AMBA |
| 105 | help |
| 106 | Enables the on-chip embedded trace macrocell and embedded trace |
| 107 | buffer driver that will allow you to collect traces of the |
| 108 | kernel code. |
| 109 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 110 | config DEBUG_DC21285_PORT |
| 111 | bool "Kernel low-level debugging messages via footbridge serial port" |
| 112 | depends on DEBUG_LL && FOOTBRIDGE |
| 113 | help |
| 114 | Say Y here if you want the debug print routines to direct their |
| 115 | output to the serial port in the DC21285 (Footbridge). Saying N |
| 116 | will cause the debug messages to appear on the first 16550 |
| 117 | serial port. |
| 118 | |
| 119 | config DEBUG_CLPS711X_UART2 |
| 120 | bool "Kernel low-level debugging messages via UART2" |
| 121 | depends on DEBUG_LL && ARCH_CLPS711X |
| 122 | help |
| 123 | Say Y here if you want the debug print routines to direct their |
| 124 | output to the second serial port on these devices. Saying N will |
| 125 | cause the debug messages to appear on the first serial port. |
| 126 | |
Ben Dooks | 3ec2052 | 2007-07-22 16:12:04 +0100 | [diff] [blame] | 127 | config DEBUG_S3C_UART |
Ben Dooks | 89f1fa0 | 2010-01-29 09:02:17 +0000 | [diff] [blame] | 128 | depends on PLAT_SAMSUNG |
Ben Dooks | 3ec2052 | 2007-07-22 16:12:04 +0100 | [diff] [blame] | 129 | int "S3C UART to use for low-level debug" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | default "0" |
| 131 | help |
Ben Dooks | 3ec2052 | 2007-07-22 16:12:04 +0100 | [diff] [blame] | 132 | Choice for UART for kernel low-level using S3C UARTS, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | should be between zero and two. The port must have been |
Egry Gabor | c41045a | 2006-06-04 21:22:11 +0100 | [diff] [blame] | 134 | initialised by the boot-loader before use. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 135 | |
| 136 | The uncompressor code port configuration is now handled |
Ben Dooks | c765784 | 2007-07-22 16:11:20 +0100 | [diff] [blame] | 137 | by CONFIG_S3C_LOWLEVEL_UART_PORT. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 138 | |
| 139 | endmenu |