Merge branch 'for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/nico/orion into fixes

    kgdb is a source level debugger for linux kernel. It is used along

    with gdb to debug a linux kernel.  The expectation is that gdb can

    be used to "break in" to the kernel to inspect memory, variables

    and look through a cal stack information similar to what an

    and look through call stack information similar to what an

    application developer would use gdb for.  It is possible to place

    breakpoints in kernel code and perform some limited execution

    stepping.

  <chapter id="CompilingAKernel">

    <title>Compiling a kernel</title>

    <para>

    To enable <symbol>CONFIG_KGDB</symbol>, look under the "Kernel debugging"

    and then select "KGDB: kernel debugging with remote gdb".

    To enable <symbol>CONFIG_KGDB</symbol> you should first turn on

    "Prompt for development and/or incomplete code/drivers"

    (CONFIG_EXPERIMENTAL) in  "General setup", then under the

    "Kernel debugging" select "KGDB: kernel debugging with remote gdb".

    </para>

    <para>

    Next you should choose one of more I/O drivers to interconnect debugging

	void (*destroy_inode)(struct inode *);

	void (*dirty_inode) (struct inode *);

	int (*write_inode) (struct inode *, int);

	void (*put_inode) (struct inode *);

	void (*drop_inode) (struct inode *);

	void (*delete_inode) (struct inode *);

	void (*put_super) (struct super_block *);

destroy_inode:		no

dirty_inode:		no				(must not sleep)

write_inode:		no

put_inode:		no

drop_inode:		no				!!!inode_lock!!!

delete_inode:		no

put_super:		yes	yes	no

        void (*dirty_inode) (struct inode *);

        int (*write_inode) (struct inode *, int);

        void (*put_inode) (struct inode *);

        void (*drop_inode) (struct inode *);

        void (*delete_inode) (struct inode *);

        void (*put_super) (struct super_block *);

	inode to disc.  The second parameter indicates whether the write

	should be synchronous or not, not all filesystems check this flag.

  put_inode: called when the VFS inode is removed from the inode

	cache.

  drop_inode: called when the last access to the inode is dropped,

	with the inode_lock spinlock held.

limits FOO to module (=m) or disabled (=n).

Build limited by a third config symbol which may be =y or =m

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

A common idiom that we see (and sometimes have problems with) is this:

When option C in B (module or subsystem) uses interfaces from A (module

or subsystem), and both A and B are tristate (could be =y or =m if they

were independent of each other, but they aren't), then we need to limit

C such that it cannot be built statically if A is built as a loadable

module.  (C already depends on B, so there is no dependency issue to

take care of here.)

If A is linked statically into the kernel image, C can be built

statically or as loadable module(s).  However, if A is built as loadable

module(s), then C must be restricted to loadable module(s) also.  This

can be expressed in kconfig language as:

config C

	depends on A = y || A = B

or for real examples, use this command in a kernel tree:

$ find . -name Kconfig\* | xargs grep -ns "depends on.*=.*||.*=" | grep -v orig

	mac5380=	[HW,SCSI] Format:

			<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>

	mac53c9x=	[HW,SCSI] Format:

			<num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>

	machvec=	[IA64] Force the use of a particular machine-vector

			(machvec) in a generic kernel.

			Example: machvec=hpzx1_swiotlb

				This is normally done in pci_enable_device(),

				so this option is a temporary workaround

				for broken drivers that don't call it.

		skip_isa_align	[X86] do not align io start addr, so can

				handle more pci cards

		firmware	[ARM] Do not re-enumerate the bus but instead

				just use the configuration from the

				bootloader. This is currently used on