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Merge up to 2.6.11
Merge of 2.6.x-xfs-melb:linux:21721a by kenmcd.

menu "Kernel hacking"

source "lib/Kconfig.debug"

config EARLY_PRINTK
	bool "Early printk" if EMBEDDED
	default y
	help
	  Write kernel log output directly into the VGA buffer or to a serial
	  port.

	  This is useful for kernel debugging when your machine crashes very
	  early before the console code is initialized. For normal operation
	  it is not recommended because it looks ugly and doesn't cooperate
	  with klogd/syslogd or the X server. You should normally N here,
	  unless you want to debug such a crash.

config DEBUG_STACKOVERFLOW
	bool "Check for stack overflows"
	depends on DEBUG_KERNEL

config KPROBES
	bool "Kprobes"
	depends on DEBUG_KERNEL
	help
	  Kprobes allows you to trap at almost any kernel address and
	  execute a callback function.  register_kprobe() establishes
	  a probepoint and specifies the callback.  Kprobes is useful
	  for kernel debugging, non-intrusive instrumentation and testing.
	  If in doubt, say "N".

config DEBUG_STACK_USAGE
	bool "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 and sysrq-P debug output.

	  This option will slow down process creation somewhat.

config DEBUG_PAGEALLOC
	bool "Page alloc debugging"
	depends on DEBUG_KERNEL
	help
	  Unmap pages from the kernel linear mapping after free_pages().
	  This results in a large slowdown, but helps to find certain types
	  of memory corruptions.

config 4KSTACKS
	bool "Use 4Kb for kernel stacks instead of 8Kb"
	help
	  If you say Y here the kernel will use a 4Kb stacksize for the
	  kernel stack attached to each process/thread. This facilitates
	  running more threads on a system and also reduces the pressure
	  on the VM subsystem for higher order allocations. This option
	  will also use IRQ stacks to compensate for the reduced stackspace.

config X86_FIND_SMP_CONFIG
	bool
	depends on X86_LOCAL_APIC || X86_VOYAGER
	default y

config X86_MPPARSE
	bool
	depends on X86_LOCAL_APIC && !X86_VISWS
	default y

config KDB
	bool "Built-in Kernel Debugger support"
	depends on DEBUG_KERNEL
	select KALLSYMS
	select KALLSYMS_ALL
	help
	  This option provides a built-in kernel debugger.  The built-in
	  kernel debugger contains commands which allow memory to be examined,
	  instructions to be disassembled and breakpoints to be set.  For details,
	  see Documentation/kdb/kdb.mm and the manual pages kdb_bt, kdb_ss, etc.
	  Kdb can also be used via the serial port.  Set up the system to
	  have a serial console (see Documentation/serial-console.txt).
	  The key sequence <escape>KDB on the serial port will cause the
	  kernel debugger to be entered with input from the serial port and
	  output to the serial console.  If unsure, say N.

config KDB_MODULES
	tristate "KDB modules"
	depends on KDB
	help
	  KDB can be extended by adding your own modules, in directory
	  kdb/modules.  This option selects the way that these modules should
	  be compiled, as free standing modules (select M) or built into the
	  kernel (select Y).  If unsure say M.

config KDB_OFF
	bool "KDB off by default"
	depends on KDB
	help
	  Normally kdb is activated by default, as long as CONFIG_KDB is set.
	  If you want to ship a kernel with kdb support but only have kdb
	  turned on when the user requests it then select this option.  When
	  compiled with CONFIG_KDB_OFF, kdb ignores all events unless you boot
	  with kdb=on or you echo "1" > /proc/sys/kernel/kdb.  This option also
	  works in reverse, if kdb is normally activated, you can boot with
	  kdb=off or echo "0" > /proc/sys/kernel/kdb to deactivate kdb. If
	  unsure, say N.

config KDB_CONTINUE_CATASTROPHIC
	int "KDB continues after catastrophic errors"
	depends on KDB
	default "0"
	help
	  This integer controls the behaviour of kdb when the kernel gets a
  	  catastrophic error, i.e. for a panic, oops, NMI or other watchdog
  	  tripping.  CONFIG_KDB_CONTINUE_CATASTROPHIC interacts with
  	  /proc/sys/kernel/kdb and CONFIG_DUMP (if your kernel has the LKCD
  	  patch).
  	  When KDB is active (/proc/sys/kernel/kdb == 1) and a catastrophic
  	  error occurs, nothing extra happens until you type 'go'.
	  CONFIG_KDB_CONTINUE_CATASTROPHIC == 0 (default).  The first time
    	  you type 'go', kdb warns you.  The second time you type 'go', KDB
    	  tries to continue - no guarantees that the kernel is still usable.
    	  CONFIG_KDB_CONTINUE_CATASTROPHIC == 1.  KDB tries to continue - no
    	  guarantees that the kernel is still usable.
    	  CONFIG_KDB_CONTINUE_CATASTROPHIC == 2.  If your kernel has the LKCD
    	  patch and LKCD is configured to take a dump then KDB forces a dump.
    	  Whether or not a dump is taken, KDB forces a reboot.
  	  When KDB is not active (/proc/sys/kernel/kdb == 0) and a catastrophic
  	  error occurs, the following steps are automatic, no human
  	  intervention is required.
    	  CONFIG_KDB_CONTINUE_CATASTROPHIC == 0 (default) or 1.  KDB attempts
    	  to continue - no guarantees that the kernel is still usable.
    	  CONFIG_KDB_CONTINUE_CATASTROPHIC == 2.  If your kernel has the LKCD
    	  patch and LKCD is configured to take a dump then KDB automatically
    	  forces a dump.  Whether or not a dump is taken, KDB forces a
    	  reboot.
  	  If you are not sure, say 0.  Read Documentation/kdb/dump.txt before
  	  setting to 2.

# KDB_USB does not work, the usb code needs to be
# converted from 2.4.19 to 2.5.40 APIs.  Omit it until somebody
# fixes CONFIG_KDB_USB.
#config KDB_USB
#	bool "Support for USB Keyboard in KDB"
#	depends on KDB && USB
#	help
#	  If you want to use kdb from a USB keyboard then say Y here.  If you
#	  say N then kdb can only be used from a PC (AT) keyboard or a serial
#	  console.

endmenu