LXR linux/arch/i386/Kconfig.debug

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