commit 51b563fc93c8cb5bff1d67a0a71c374e4a4ea049 upstream.

Albin Tonnerre <albin.tonnerre@free-electrons.com> reported:

    Bash 4 filters out variables which contain a dot in them.
    This happends to be the case of CPPFLAGS_vmlinux.lds.
    This is rather unfortunate, as it now causes
    build failures when using SHELL=/bin/bash to compile,
    or when bash happens to be used by make (eg when it's /bin/sh)

Remove the common definition of CPPFLAGS_vmlinux.lds by
pushing relevant stuff to either Makefile.build or the
arch specific kernel/Makefile where we build the linker script.

This is also nice cleanup as we move the information out where
it is used.

Notes for the different architectures touched:

arm - we use an already exported symbol
cris - we use a config symbol aleady available
       [Not build tested]
mips - the jiffies complexity has moved to vmlinux.lds.S where we need it.
       Added a few variables to CPPFLAGS - they are only used by
       the linker script.
       [Not build tested]
powerpc - removed assignment that is not needed
          [not build tested]
sparc - simplified it using $(BITS)
um - introduced a few new exported variables to deal with this
xtensa - added options to CPP invocation
         [not build tested]

Cc: Albin Tonnerre <albin.tonnerre@free-electrons.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

preserve_crunch_context() calls __copy_to_user() which expects the
destination address to be in __user space.  setup_sigframe() properly
passes the destination address.

restore_crunch_context() calls __copy_from_user() which expects the
source address to be in __user space.  restore_sigframe() properly
passes the source address.

This fixes {preserve/restore}_crunch_context() to accept the
address as __user space and resolves the following sparse warnings:

  arch/arm/kernel/signal.c:146:31:
     warning: incorrect type in argument 1 (different address spaces)
        expected void [noderef] <asn:1>*to
        got struct crunch_sigframe *frame

  arch/arm/kernel/signal.c:156:38:
     warning: incorrect type in argument 2 (different address spaces)
        expected void const [noderef] <asn:1>*from
        got struct crunch_sigframe *frame

  arch/arm/kernel/signal.c:250:48:
     warning: incorrect type in argument 1 (different address spaces)
        expected struct crunch_sigframe *frame
        got struct crunch_sigframe [noderef] <asn:1>*<noident>

  arch/arm/kernel/signal.c:365:49:
     warning: incorrect type in argument 1 (different address spaces)
        expected struct crunch_sigframe *frame
        got struct crunch_sigframe [noderef] <asn:1>*<noident>

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

After ftrace_trace_function is called r1 is probably clobbered so don't
try to use its value for restoring.

This was introduced in v2.6.29~38^2~7

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Update the link script for ARM to use PAGE_SIZE instead of hard-
coded 4096. Also the old RODATA macro is deprecated
for the RO_DATA(PAGE_SIZE) macro. As a consequence the PAGE_SIZE
was changed from (1UL << PAGE_SHIFT) to (_AC(1,UL) << PAGE_SHIFT)
because the linker does not understand the "UL" suffix to numeric
constants.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

handle_bad_irq() expects the IRQ number to be valid (used for statistics),
so it cannot be called with an illegal vector. The problem was reported
by a static analysis tool.

The change makes bad_irq_desc redundant, so delete it.

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

pm_idle is used by infrastructure (eg, cpuidle) which expects architectures
to call it in a certain way.  Arrange for ARM to follow x86's lead on this
and call pm_idle() with interrupts already disabled.  However, we expect
pm_idle() to enable interrupts before it returns.

Also, OMAP wants to be able to disable hlt-ing, so allow hlt_counter to
prevent all calls to pm_idle.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

When a kthread function returns, it branches to do_exit(). However, the
unwinding information isn't valid anymore and any stack trace caused by
do_exit() may be incorrect. This patch adds a kernel_thread_exit()
function and annotated with '.cantunwind' so that the unwinder stops
when reaching it.

Tested-by: Tony Lindgren <tony@atomide.com>

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

There are situations where the unwinder goes beyond stack boundaries and
unwinds random data. This patch moves the stack boundaries check after
the unwind_exec_insn() call and adds an extra check for possible
infinite loops (like "mov pc, lr" with pc == lr).

The patch also fixes a bug in the unwind instructions interpreter. The
0xb0 instruction can only set PC to LR if this wasn't already set by
a previous instruction (this is used on exceptions taken while in kernel
mode where svc_entry is annotated with ".save {r0 - pc}").

Tested-by: Tony Lindgren <tony@atomide.com>

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Not discarding these sections when hotplug isn't available prevents the
kernel from building.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>