Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | menu "Kernel hacking" |
| 2 | |
| 3 | source "lib/Kconfig.debug" |
| 4 | |
| 5 | config EARLY_PRINTK |
| 6 | bool "Early printk" if EMBEDDED && DEBUG_KERNEL |
| 7 | default y |
| 8 | help |
| 9 | Write kernel log output directly into the VGA buffer or to a serial |
| 10 | port. |
| 11 | |
| 12 | This is useful for kernel debugging when your machine crashes very |
| 13 | early before the console code is initialized. For normal operation |
| 14 | it is not recommended because it looks ugly and doesn't cooperate |
| 15 | with klogd/syslogd or the X server. You should normally N here, |
| 16 | unless you want to debug such a crash. |
| 17 | |
| 18 | config DEBUG_STACKOVERFLOW |
| 19 | bool "Check for stack overflows" |
| 20 | depends on DEBUG_KERNEL |
Adrian Bunk | dab175f | 2005-07-27 11:44:23 -0700 | [diff] [blame] | 21 | help |
| 22 | This option will cause messages to be printed if free stack space |
| 23 | drops below a certain limit. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | config DEBUG_STACK_USAGE |
| 26 | bool "Stack utilization instrumentation" |
| 27 | depends on DEBUG_KERNEL |
| 28 | help |
| 29 | Enables the display of the minimum amount of free stack which each |
| 30 | task has ever had available in the sysrq-T and sysrq-P debug output. |
| 31 | |
| 32 | This option will slow down process creation somewhat. |
| 33 | |
Chuck Ebbert | 4d7d8c8 | 2006-03-23 02:59:30 -0800 | [diff] [blame] | 34 | config STACK_BACKTRACE_COLS |
| 35 | int "Stack backtraces per line" if DEBUG_KERNEL |
| 36 | range 1 3 |
| 37 | default 2 |
| 38 | help |
| 39 | Selects how many stack backtrace entries per line to display. |
| 40 | |
| 41 | This can save screen space when displaying traces. |
| 42 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | comment "Page alloc debug is incompatible with Software Suspend on i386" |
| 44 | depends on DEBUG_KERNEL && SOFTWARE_SUSPEND |
| 45 | |
| 46 | config DEBUG_PAGEALLOC |
Andrew Morton | 4a2f0ac | 2006-03-25 03:07:22 -0800 | [diff] [blame] | 47 | bool "Debug page memory allocations" |
Chen, Kenneth W | a7d06ca | 2006-03-25 03:06:50 -0800 | [diff] [blame] | 48 | depends on DEBUG_KERNEL && !SOFTWARE_SUSPEND && !HUGETLBFS |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | help |
| 50 | Unmap pages from the kernel linear mapping after free_pages(). |
| 51 | This results in a large slowdown, but helps to find certain types |
| 52 | of memory corruptions. |
| 53 | |
Arjan van de Ven | 63aaf30 | 2006-01-06 00:12:02 -0800 | [diff] [blame] | 54 | config DEBUG_RODATA |
| 55 | bool "Write protect kernel read-only data structures" |
| 56 | depends on DEBUG_KERNEL |
| 57 | help |
| 58 | Mark the kernel read-only data as write-protected in the pagetables, |
| 59 | in order to catch accidental (and incorrect) writes to such const |
| 60 | data. This option may have a slight performance impact because a |
| 61 | portion of the kernel code won't be covered by a 2MB TLB anymore. |
| 62 | If in doubt, say "N". |
| 63 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 64 | config 4KSTACKS |
| 65 | bool "Use 4Kb for kernel stacks instead of 8Kb" |
| 66 | depends on DEBUG_KERNEL |
| 67 | help |
| 68 | If you say Y here the kernel will use a 4Kb stacksize for the |
| 69 | kernel stack attached to each process/thread. This facilitates |
| 70 | running more threads on a system and also reduces the pressure |
| 71 | on the VM subsystem for higher order allocations. This option |
| 72 | will also use IRQ stacks to compensate for the reduced stackspace. |
| 73 | |
| 74 | config X86_FIND_SMP_CONFIG |
| 75 | bool |
| 76 | depends on X86_LOCAL_APIC || X86_VOYAGER |
| 77 | default y |
| 78 | |
| 79 | config X86_MPPARSE |
| 80 | bool |
| 81 | depends on X86_LOCAL_APIC && !X86_VISWS |
| 82 | default y |
| 83 | |
Andi Kleen | 102e41f | 2006-04-18 12:35:22 +0200 | [diff] [blame] | 84 | config DOUBLEFAULT |
| 85 | default y |
| 86 | bool "Enable doublefault exception handler" if EMBEDDED |
| 87 | help |
| 88 | This option allows trapping of rare doublefault exceptions that |
| 89 | would otherwise cause a system to silently reboot. Disabling this |
| 90 | option saves about 4k and might cause you much additional grey |
| 91 | hair. |
| 92 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 93 | endmenu |