There are a few places in the kernel where the init task is signaled.  The
ctrl+alt+del sequence is one them.  It kills a task, usually init, using a
cached pid (cad_pid).

This patch replaces the pid_t by a struct pid to avoid pid wrap around
problem.  The struct pid is initialized at boot time in init() and can be
modified through systctl with

	/proc/sys/kernel/cad_pid

[ I haven't found any distro using it ? ]

It also introduces a small helper routine kill_cad_pid() which is used
where it seemed ok to use cad_pid instead of pid 1.

[akpm@osdl.org: cleanups, build fix]
Signed-off-by: NCedric Le Goater <clg@fr.ibm.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Currently the snsc driver uses force_sig to send init a SIGPWR when the
system overheats.  This patch switches it to kill_proc instead which has
the following advantages:

 (1) gets rid of one of the last remaining tasklist_lock users
     in modular code
 (2) simplifies the snsc code significantly

The downside is that an init implementation could in theory block SIGPWR
and it would not get delivered.  The sysvinit code used by all major
distributions doesn't do this and blocking this signal in init would be a
rather stupid thing to do.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Change driver to use kzalloc rather than kmalloc+memset
Signed-off-by: NJes Sorensen <jes@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Handle system controller power down pending events
on SN systems. This allows the system to gracefully shutdown
before the system controller removes power due to
an adverse environmental condition.
Signed-off-by: NAaron Young <ayoung@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

It's been pointed out that environmental events from the system
controllers on Altix machines cause the kernel to complain about
unaligned memory accesses.  This turns out to be because
"be32_to_cpup()" didn't do everything I thought/hoped it did.
I've added calls to pull the offending integers out of the
buffers using get_unaligned() before feeding them to
be32_to_cpup().
Signed-off-by: NGreg Howard <ghoward@sgi.com>
Signed-off-by: NTony Luck <tony.luck@intel.com>

Forgot the "bk new" to add this file. Part of the patch
from Greg Howard
Signed-off-by: NTony Luck <tony.luck@intel.com>