Al viro broke us with

commit edd63a2763bdae0daa4f0a4d4c5d61d1154352a5
Author: Al Viro <viro@zeniv.linux.org.uk>
Date:   Fri Apr 27 13:42:45 2012 -0400

    set_restore_sigmask() is never called without SIGPENDING (and never should be)

Although it's pretty much our fault since parisc's asm/bug.h uses
BUGWARN_TAINT but doesn't include the file that defines it.  Fix that.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>

WARN() is used in some places to report firmware or hardware bugs that
are then worked-around.  These bugs do not affect the stability of the
kernel and should not set the flag for TAINT_WARN.  To allow for this,
add WARN_TAINT() and WARN_TAINT_ONCE() macros that take a taint number
as argument.

Architectures that implement warnings using trap instructions instead
of calls to warn_slowpath_*() now implement __WARN_TAINT(taint)
instead of __WARN().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Acked-by: Helge Deller <deller@gmx.de>
Tested-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>

Use the new unreachable() macro instead of for(;;);

Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>