Pull ARM fixes from Russell King:
 "The usual random collection of relatively small ARM fixes"

* 'fixes' of git://ftp.arm.linux.org.uk/~rmk/linux-arm:
  ARM: 8063/1: bL_switcher: fix individual online status reporting of removed CPUs
  ARM: 8064/1: fix v7-M signal return
  ARM: 8057/1: amba: Add Qualcomm vendor ID.
  ARM: 8052/1: unwind: Fix handling of "Pop r4-r[4+nnn],r14" opcode
  ARM: 8051/1: put_user: fix possible data corruption in put_user
  ARM: 8048/1: fix v7-M setup stack location

According to arm procedure call standart r2 register is call-cloberred.
So after the result of x expression was put into r2 any following
function call in p may overwrite r2. To fix this, the result of p
expression must be saved to the temporary variable before the
assigment x expression to __r2.

Signed-off-by: Andrey Ryabinin <a.ryabinin@samsung.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The setup_max_cpus variable is only defined if CONFIG_SMP is set. Add
a preprocessor condition to avoid the following compilation error if
CONFIG_SMP is not set:

    arch/arm/include/asm/trusted_foundations.h: In function 'register_trusted_foundations':
    arch/arm/include/asm/trusted_foundations.h:57:2: error: 'setup_max_cpus' undeclared (first use in this function)

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Acked-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Pull xen bug fixes from David Vrabel:
 - Fix arm64 crash on boot.
 - Quiet a noisy arm build warning (virt_to_pfn() redefined).

* tag 'stable/for-linus-3.15-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  arm64: introduce virt_to_pfn
  xen/events/fifo: correctly align bitops
  arm/xen: Remove definiition of virt_to_pfn in asm/xen/page.h

virt_to_pfn has been defined in asm/memory.h by the commit e26a9e0 "ARM: Better
virt_to_page() handling"

This will result of a compilation warning when CONFIG_XEN is enabled.

arch/arm/include/asm/xen/page.h:80:0: warning: "virt_to_pfn" redefined [enabled by default]
 #define virt_to_pfn(v)          (PFN_DOWN(__pa(v)))
 ^
In file included from arch/arm/include/asm/page.h:163:0,
                 from arch/arm/include/asm/xen/page.h:4,
                 from include/xen/page.h:4,
                 from arch/arm/xen/grant-table.c:33:

The definition in memory.h is nearly the same (it directly expand PFN_DOWN),
so we can safely drop virt_to_pfn in xen include.

Signed-off-by: Julien Grall <julien.grall@linaro.org>
Signed-off-by: David Vrabel <david.vrabel@citrix.com>

This merges the patch to fix possible loss of dirty bit on munmap() or
madvice(DONTNEED).  If there are concurrent writers on other CPU's that
have the unmapped/unneeded page in their TLBs, their writes to the page
could possibly get lost if a third CPU raced with the TLB flush and did
a page_mkclean() before the page was fully written.

Admittedly, if you unmap() or madvice(DONTNEED) an area _while_ another
thread is still busy writing to it, you deserve all the lost writes you
could get.  But we kernel people hold ourselves to higher quality
standards than "crazy people deserve to lose", because, well, we've seen
people do all kinds of crazy things.

So let's get it right, just because we can, and we don't have to worry
about it.

* safe-dirty-tlb-flush:
  mm: split 'tlb_flush_mmu()' into tlb flushing and memory freeing parts

The mmu-gather operation 'tlb_flush_mmu()' has done two things: the
actual tlb flush operation, and the batched freeing of the pages that
the TLB entries pointed at.

This splits the operation into separate phases, so that the forced
batched flushing done by zap_pte_range() can now do the actual TLB flush
while still holding the page table lock, but delay the batched freeing
of all the pages to after the lock has been dropped.

This in turn allows us to avoid a race condition between
set_page_dirty() (as called by zap_pte_range() when it finds a dirty
shared memory pte) and page_mkclean(): because we now flush all the
dirty page data from the TLB's while holding the pte lock,
page_mkclean() will be held up walking the (recently cleaned) page
tables until after the TLB entries have been flushed from all CPU's.

Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit fdb487f5c961b94486a78fa61fa28b8eff1954ab
  ("ARM: 8015/1: Add cpu_is_pj4 to distinguish PJ4 because it
    has some differences with V7")
introduced a cpuid check for Marvell PJ4 processors to fix a
regression caused by adding PJ4 based Marvell Dove into
multi_v7.

Unfortunately, this check is too narrow to catch PJ4 used on
Dove itself and breaks iWMMXt support.

This patch therefore relaxes the cpuid mask to match both PJ4
and PJ4B. Also, rework the given comment about PJ4/PJ4B
modifications to be a little bit more specific about the
differences.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The switcher should not depend on MAX_CLUSTER to determine ifit should
be activated or not. In a multiplatform kernel binary it is possible to
have dual-cluster and quad-cluster platforms configured in. In that case
MAX_CLUSTER which is a build time limit should be 4 and that shouldn't
prevent the switcher from working if the kernel is booted on a b.L
dual-cluster system.

In bL_switcher_halve_cpus() we already have a runtime validation check
to make sure we're dealing with only two clusters, so booting on a quad
cluster system will be caught and switcher activation aborted.

However, the b.L switcher must ensure the MCPM layer is initialized on
the booted hardware before doing anything.  The mcpm_is_available()
function is added to that effect.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Abhilash Kesavan <kesavan.abhilash@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>