In split page table lock case, we embed spinlock_t into struct page.
For obvious reason, we don't want to increase size of struct page if
spinlock_t is too big, like with DEBUG_SPINLOCK or DEBUG_LOCK_ALLOC or
on -rt kernel.  So we disable split page table lock, if spinlock_t is
too big.

This patchset allows to allocate the lock dynamically if spinlock_t is
big.  In this page->ptl is used to store pointer to spinlock instead of
spinlock itself.  It costs additional cache line for indirect access,
but fix page fault scalability for multi-threaded applications.

LOCK_STAT depends on DEBUG_SPINLOCK, so on current kernel enabling
LOCK_STAT to analyse scalability issues breaks scalability.  ;)

The patchset mostly fixes this.  Results for ./thp_memscale -c 80 -b 512M
on 4-socket machine:

baseline, no CONFIG_LOCK_STAT:	9.115460703 seconds time elapsed
baseline, CONFIG_LOCK_STAT=y:	53.890567123 seconds time elapsed
patched, no CONFIG_LOCK_STAT:	8.852250368 seconds time elapsed
patched, CONFIG_LOCK_STAT=y:	11.069770759 seconds time elapsed

Patch count is scary, but most of them trivial. Overview:

 Patches 1-4	Few bug fixes. No dependencies to other patches.
		Probably should applied as soon as possible.

 Patch 5	Changes signature of pgtable_page_ctor(). We will use it
		for dynamic lock allocation, so it can fail.

 Patches 6-8	Add missing constructor/destructor calls on few archs.
		It's fixes NR_PAGETABLE accounting and prepare to use
		split ptl.

 Patches 9-33	Add pgtable_page_ctor() fail handling to all archs.

 Patches 34	Finally adds support of dynamically-allocated page->pte.
		Also contains documentation for split page table lock.

This patch (of 34):

I've missed that we preallocate few pmds on pgd_alloc() if X86_PAE
enabled.  Let's add missed constructor/destructor calls.

I haven't noticed it during testing since prep_new_page() clears
page->mapping and therefore page->ptl.  It's effectively equal to
spin_lock_init(&page->ptl).
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Guan Xuetao <gxt@mprc.pku.edu.cn>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Enable PMD split page table lock for X86_64 and PAE.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: NAlex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Reviewed-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently mm->pmd_huge_pte protected by page table lock.  It will not
work with split lock.  We have to have per-pmd pmd_huge_pte for proper
access serialization.

For now, let's just introduce wrapper to access mm->pmd_huge_pte.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: NAlex Thorlton <athorlton@sgi.com>
Cc: Alex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We're going to introduce split page table lock for PMD level.  Let's
rename existing split ptlock for PTE level to avoid confusion.
Signed-off-by: NKirill A. Shutemov <kirill.shutemov@linux.intel.com>
Tested-by: NAlex Thorlton <athorlton@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: "Paul E . McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The get_dumpable() return value is not boolean.  Most users of the
function actually want to be testing for non-SUID_DUMP_USER(1) rather than
SUID_DUMP_DISABLE(0).  The SUID_DUMP_ROOT(2) is also considered a
protected state.  Almost all places did this correctly, excepting the two
places fixed in this patch.

Wrong logic:
    if (dumpable == SUID_DUMP_DISABLE) { /* be protective */ }
        or
    if (dumpable == 0) { /* be protective */ }
        or
    if (!dumpable) { /* be protective */ }

Correct logic:
    if (dumpable != SUID_DUMP_USER) { /* be protective */ }
        or
    if (dumpable != 1) { /* be protective */ }

Without this patch, if the system had set the sysctl fs/suid_dumpable=2, a
user was able to ptrace attach to processes that had dropped privileges to
that user.  (This may have been partially mitigated if Yama was enabled.)

The macros have been moved into the file that declares get/set_dumpable(),
which means things like the ia64 code can see them too.

CVE-2013-2929
Reported-by: NVasily Kulikov <segoon@openwall.com>
Signed-off-by: NKees Cook <keescook@chromium.org>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since gen_pool_dma_alloc() is introduced, we implement it to simplify code.
Signed-off-by: NNicolin Chen <b42378@freescale.com>
Cc: Sekhar Nori <nsekhar@ti.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Only a couple of arches (sh/x86) use fpu_counter in task_struct so it can
be moved out into ARCH specific thread_struct, reducing the size of
task_struct for other arches.

Compile tested i386_defconfig + gcc 4.7.3
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Acked-by: NIngo Molnar <mingo@kernel.org>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Only a couple of arches (sh/x86) use fpu_counter in task_struct so it can
be moved out into ARCH specific thread_struct, reducing the size of
task_struct for other arches.

Compile tested sh defconfig + sh4-linux-gcc (4.6.3)
Signed-off-by: NVineet Gupta <vgupta@synopsys.com>
Cc: Paul Mundt <paul.mundt@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

glibc recently changed the error string for ESTALE to remove "NFS" -

https://sourceware.org/git/?p=glibc.git;a=commitdiff;h=96945714ec61951cc748da2b4b8a80cf02127ee9

from: [ERR_REMAP (ESTALE)] = N_("Stale NFS file handle"),
to:   [ERR_REMAP (ESTALE)] = N_("Stale file handle"),

And some have expressed concern that the kernel's errno.h
comments still refer to NFS.

So make that change... note that this is a comment-only change,
and has no functional difference.
Signed-off-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The hot-Pluggable field in SRAT specifies which memory is hotpluggable.
As we mentioned before, if hotpluggable memory is used by the kernel, it
cannot be hot-removed.  So memory hotplug users may want to set all
hotpluggable memory in ZONE_MOVABLE so that the kernel won't use it.

Memory hotplug users may also set a node as movable node, which has
ZONE_MOVABLE only, so that the whole node can be hot-removed.

But the kernel cannot use memory in ZONE_MOVABLE.  By doing this, the
kernel cannot use memory in movable nodes.  This will cause NUMA
performance down.  And other users may be unhappy.

So we need a way to allow users to enable and disable this functionality.
In this patch, we introduce movable_node boot option to allow users to
choose to not to consume hotpluggable memory at early boot time and later
we can set it as ZONE_MOVABLE.

To achieve this, the movable_node boot option will control the memblock
allocation direction.  That said, after memblock is ready, before SRAT is
parsed, we should allocate memory near the kernel image as we explained in
the previous patches.  So if movable_node boot option is set, the kernel
does the following:

1. After memblock is ready, make memblock allocate memory bottom up.
2. After SRAT is parsed, make memblock behave as default, allocate memory
   top down.

Users can specify "movable_node" in kernel commandline to enable this
functionality.  For those who don't use memory hotplug or who don't want
to lose their NUMA performance, just don't specify anything.  The kernel
will work as before.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Suggested-by: NKamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Suggested-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Memory reserved for crashkernel could be large.  So we should not allocate
this memory bottom up from the end of kernel image.

When SRAT is parsed, we will be able to know which memory is hotpluggable,
and we can avoid allocating this memory for the kernel.  So reorder
reserve_crashkernel() after SRAT is parsed.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The Linux kernel cannot migrate pages used by the kernel.  As a result,
kernel pages cannot be hot-removed.  So we cannot allocate hotpluggable
memory for the kernel.

In a memory hotplug system, any numa node the kernel resides in should be
unhotpluggable.  And for a modern server, each node could have at least
16GB memory.  So memory around the kernel image is highly likely
unhotpluggable.

ACPI SRAT (System Resource Affinity Table) contains the memory hotplug
info.  But before SRAT is parsed, memblock has already started to allocate
memory for the kernel.  So we need to prevent memblock from doing this.

So direct memory mapping page tables setup is the case.
init_mem_mapping() is called before SRAT is parsed.  To prevent page
tables being allocated within hotpluggable memory, we will use bottom-up
direction to allocate page tables from the end of kernel image to the
higher memory.

Note:
As for allocating page tables in lower memory, TJ said:

: This is an optional behavior which is triggered by a very specific kernel
: boot param, which I suspect is gonna need to stick around to support
: memory hotplug in the current setup unless we add another layer of address
: translation to support memory hotplug.

As for page tables may occupy too much lower memory if using 4K mapping
(CONFIG_DEBUG_PAGEALLOC and CONFIG_KMEMCHECK both disable using >4k
pages), TJ said:

: But as I said in the same paragraph, parsing SRAT earlier doesn't solve
: the problem in itself either.  Ignoring the option if 4k mapping is
: required and memory consumption would be prohibitive should work, no?
: Something like that would be necessary if we're gonna worry about cases
: like this no matter how we implement it, but, frankly, I'm not sure this
: is something worth worrying about.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Create a new function memory_map_top_down to factor out of the top-down
direct memory mapping pagetable setup.  This is also a preparation for the
following patch, which will introduce the bottom-up memory mapping.  That
said, we will put the two ways of pagetable setup into separate functions,
and choose to use which way in init_mem_mapping, which makes the code more
clear.
Signed-off-by: NTang Chen <tangchen@cn.fujitsu.com>
Signed-off-by: NZhang Yanfei <zhangyanfei@cn.fujitsu.com>
Acked-by: NTejun Heo <tj@kernel.org>
Acked-by: NToshi Kani <toshi.kani@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Thomas Renninger <trenn@suse.de>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Jiang Liu <jiang.liu@huawei.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Implement mmap base randomization for the bottom up direction, so ASLR
works for both mmap layouts on s390.  See also commit df54d6fa ("x86
get_unmapped_area(): use proper mmap base for bottom-up direction").
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Cc: Radu Caragea <sinaelgl@gmail.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use more appropriate NUMA_NO_NODE instead of -1 in all archs' module_alloc()
Signed-off-by: NJianguo Wu <wujianguo@huawei.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use "pgdat_end_pfn()" instead of "pgdat->node_start_pfn +
pgdat->node_spanned_pages".  Simplify the code, no functional change.
Signed-off-by: NXishi Qiu <qiuxishi@huawei.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The callers of free_pgd_range() and hugetlb_free_pgd_range() don't hold
page table locks.  The comments seems to be obsolete, so let's remove
them.
Signed-off-by: NNaoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Use __free_reserved_page() to simplify the code in arch.

It used split_page() in consistent_alloc()/__dma_alloc_coherent()/dma_alloc_coherent(),
so page->_count == 1, and we can free it safely.

__free_reserved_page()
	ClearPageReserved()
	init_page_count()  // it won't change the value
	__free_page()
Signed-off-by: NXishi Qiu <qiuxishi@huawei.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

On cris arch, the functions below aren't defined:

  drivers/media/platform/sh_veu.c: In function 'sh_veu_reg_read':

  drivers/media/platform/sh_veu.c:228:2: error: implicit declaration of function 'ioread32' [-Werror=implicit-function-declaration]
  drivers/media/platform/sh_veu.c: In function 'sh_veu_reg_write':

  drivers/media/platform/sh_veu.c:234:2: error: implicit declaration of function 'iowrite32' [-Werror=implicit-function-declaration]
  drivers/media/platform/vsp1/vsp1.h: In function 'vsp1_read':
  drivers/media/platform/vsp1/vsp1.h:66:2: error: implicit declaration of function 'ioread32' [-Werror=implicit-function-declaration]
  drivers/media/platform/vsp1/vsp1.h: In function 'vsp1_write':
  drivers/media/platform/vsp1/vsp1.h:71:2: error: implicit declaration of function 'iowrite32' [-Werror=implicit-function-declaration]
  drivers/media/platform/vsp1/vsp1.h: In function 'vsp1_read':
  drivers/media/platform/vsp1/vsp1.h:66:2: error: implicit declaration of function 'ioread32' [-Werror=implicit-function-declaration]
  drivers/media/platform/vsp1/vsp1.h: In function 'vsp1_write':
  drivers/media/platform/vsp1/vsp1.h:71:2: error: implicit declaration of function 'iowrite32' [-Werror=implicit-function-declaration]
  drivers/media/platform/soc_camera/rcar_vin.c: In function 'rcar_vin_setup':
  drivers/media/platform/soc_camera/rcar_vin.c:284:3: error: implicit declaration of function 'iowrite32' [-Werror=implicit-function-declaration]

  drivers/media/platform/soc_camera/rcar_vin.c: In function 'rcar_vin_request_capture_stop':
  drivers/media/platform/soc_camera/rcar_vin.c:353:2: error: implicit declaration of function 'ioread32' [-Werror=implicit-function-declaration]

Yet, they're available, as CONFIG_GENERIC_IOMAP is defined.  What happens
is that asm/io.h was not including asm-generic/iomap.h.
Suggested-by: NBen Hutchings <ben@decadent.org.uk>
Signed-off-by: NMauro Carvalho Chehab <m.chehab@samsung.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Remove useless variable 'regs' to avoid the related warnings (warning is
treated as error).
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

'fn' is not defined, according to the implementation copy_thread() in
'sh32', need use 'usp' instead of.
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Do it the same way as done in microcode_intel.c: use pr_debug()
for missing firmware files.

There seem to be CPUs out there for which no microcode update
has been submitted to kernel-firmware repo yet resulting in
scary sounding error messages in dmesg:

  microcode: failed to load file amd-ucode/microcode_amd_fam16h.bin
Signed-off-by: NThomas Renninger <trenn@suse.de>
Acked-by: NBorislav Petkov <bp@suse.de>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/1384274383-43510-1-git-send-email-trenn@suse.deSigned-off-by: NIngo Molnar <mingo@kernel.org>

Consider a kernel crash in a module, simulated the following way:

 static int my_init(void)
 {
         char *map = (void *)0x5;
         *map = 3;
         return 0;
 }
 module_init(my_init);

When we turn off FRAME_POINTERs, the very first instruction in
that function causes a BUG. The problem is that we print IP in
the BUG report using %pB (from printk_address). And %pB
decrements the pointer by one to fix printing addresses of
functions with tail calls.

This was added in commit 71f9e598 ("x86, dumpstack: Use
%pB format specifier for stack trace") to fix the call stack
printouts.

So instead of correct output:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000005
  IP: [<ffffffffa01ac000>] my_init+0x0/0x10 [pb173]

We get:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000005
  IP: [<ffffffffa0152000>] 0xffffffffa0151fff

To fix that, we use %pS only for stack addresses printouts (via
newly added printk_stack_address) and %pB for regs->ip (via
printk_address). I.e. we revert to the old behaviour for all
except call stacks. And since from all those reliable is 1, we
remove that parameter from printk_address.
Signed-off-by: NJiri Slaby <jslaby@suse.cz>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: joe@perches.com
Cc: jirislaby@gmail.com
Link: http://lkml.kernel.org/r/1382706418-8435-1-git-send-email-jslaby@suse.czSigned-off-by: NIngo Molnar <mingo@kernel.org>

This reverts commit 8eba1842.

uv_trace() is not used by anything, nor is uv_trace_nmi_func, nor
uv_trace_func.

That's not how we do instrumentation code in the kernel: we add
tracepoints, printk()s, etc. so that everyone not just those with
magic kernel modules can debug a system.

So remove this unused (and misguied) piece of code.
Signed-off-by: NIngo Molnar <mingo@kernel.org>
Cc: Mike Travis <travis@sgi.com>
Cc: Dimitri Sivanich <sivanich@sgi.com>
Cc: Hedi Berriche <hedi@sgi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Jason Wessel <jason.wessel@windriver.com>
Link: http://lkml.kernel.org/n/tip-tumfBffmr4jmnt8Gyxanoblg@git.kernel.org

Tracepoints are named hierachially, and it makes more sense to keep a
general flow of information level from general to specific from left
to right, i.e.

	x86_exceptions.page_fault_user|kernel

rather than

	x86_exceptions.user|kernel_page_fault
Suggested-by: NIngo Molnar <mingo@kernel.org>
Acked-by: NSeiji Aguchi <seiji.aguchi@hds.com>
Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/20131111082955.GB12405@gmail.com

Commit b5b4bb3f (of: only include prom.h on sparc) removed implicit
includes of of_*.h headers by powerpc's prom.h. Some components were
missed in initial clean-up patch, so add the necessary includes to fix
powerpc builds.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-ide@vger.kernel.org
Cc: linux-crypto@vger.kernel.org

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

dump_skip to given alignment...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

just getting rid of bitrot
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

In current kernel wide source code, except other architectures, only
s390 scsi drivers use atomic_clear_mask(), and arm/arm64 need not
support s390 drivers.

So remove atomic_clear_mask() from "arm[64]/include/asm/atomic.h".
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

For atomic_cmpxchg(), the type of 'oldval' need be 'int' to match the
type of "*ptr" (used by 'ldrex' instruction) and 'old' (used by 'teq'
instruction).
Reviewed-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

atomic* value is signed value, and atomic* functions need also process
signed value (parameter value, and return value), so 32-bit arm need
use 'long long' instead of 'u64'.

After replacement, it will also fix a bug for atomic64_add_negative():
"u64 is never less than 0".

The modifications are:

  in vim, use "1,% s/\<u64\>/long long/g" command.
  remove '__aligned(8)' which is useless for 64-bit.
  be sure of 80 column limitation after replacement.
Acked-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NChen Gang <gang.chen@asianux.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

If we're running a kernel compiled with SMP_ON_UP=y and the
hardware only supports UP operation there isn't any
smp_cross_call function assigned. Unfortunately, we call
smp_cross_call() unconditionally in arch_irq_work_raise() and
crash the kernel on UP devices. Check to make sure we're running
on an SMP device before calling smp_cross_call() here.

Unable to handle kernel NULL pointer dereference at virtual address 00000000
pgd = c0004000
[00000000] *pgd=00000000
Internal error: Oops: 80000005 [#1] SMP ARM
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.12.0-rc6-00018-g8d451442-dirty #16
task: de05b440 ti: de05c000 task.ti: de05c000
PC is at 0x0
LR is at arch_irq_work_raise+0x3c/0x48
pc : [<00000000>]    lr : [<c0019590>]    psr: 60000193
sp : de05dd60  ip : 00000001  fp : 00000000
r10: c085e2f0  r9 : de05c000  r8 : c07be0a4
r7 : de05c000  r6 : de05c000  r5 : c07c5778  r4 : c0824554
r3 : 00000000  r2 : 00000000  r1 : 00000006  r0 : c0529a58
Flags: nZCv  IRQs off  FIQs on  Mode SVC_32  ISA ARM Segment kernel
Control: 10c5387d  Table: 80004019  DAC: 00000017
Process swapper/0 (pid: 1, stack limit = 0xde05c248)
Stack: (0xde05dd60 to 0xde05e000)
dd60: c07b9dbc c00cb2dc 00000001 c08242c0 c08242c0 60000113 c07be0a8 c00b0590
dd80: de05c000 c085e2f0 c08242c0 c08242c0 c1414c28 c00b07cc de05b440 c1414c28
dda0: c08242c0 c00b0af8 c0862bb0 c0862db0 c1414cd8 de05c028 c0824840 de05ddb8
ddc0: 00000000 00000009 00000001 00000024 c07be0a8 c07be0a4 de05c000 c085e2f0
dde0: 00000000 c004a4b0 00000010 de00d2dc 00000054 00000100 00000024 00000000
de00: de05c028 0000000a ffff8ae7 00200040 00000016 de05c000 60000193 de05c000
de20: 00000054 00000000 00000000 00000000 00000000 c004a704 00000000 de05c008
de40: c07ba254 c004aa1c c07c5778 c0014b70 fa200000 00000054 de05de80 c0861244
de60: 00000000 c0008634 de05b440 c051c778 20000113 ffffffff de05deb4 c051d0a4
de80: 00000001 00000001 00000000 de05b440 c082afac de057ac0 de057ac0 de0443c0
dea0: 00000000 00000000 00000000 00000000 c082afbc de05dec8 c009f2a0 c051c778
dec0: 20000113 ffffffff 00000000 c016edb0 00000000 000002b0 de057ac0 de057ac0
dee0: 00000000 c016ee40 c0875e50 de05df2e de057ac0 00000000 00000013 00000000
df00: 00000000 c016f054 de043600 de0443c0 c008eb38 de004ec0 c0875e50 c008eb44
df20: 00000012 00000000 00000000 3931f0f8 00000000 00000000 00000014 c0822e84
df40: 00000000 c008ed2c 00000000 00000000 00000000 c07b7490 c07b7490 c075ab3c
df60: 00000000 c00701ac 00000002 00000000 c0070160 dffadb73 7bf8edb4 00000000
df80: c051092c 00000000 00000000 00000000 00000000 00000000 00000000 c0510934
dfa0: de05aa40 00000000 c051092c c0013ce8 00000000 00000000 00000000 00000000
dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 07efffe5 4dfac6f5
[<c0019590>] (arch_irq_work_raise+0x3c/0x48) from [<c00cb2dc>] (irq_work_queue+0xe4/0xf8)
[<c00cb2dc>] (irq_work_queue+0xe4/0xf8) from [<c00b0590>] (rcu_accelerate_cbs+0x1d4/0x1d8)
[<c00b0590>] (rcu_accelerate_cbs+0x1d4/0x1d8) from [<c00b07cc>] (rcu_start_gp+0x34/0x48)
[<c00b07cc>] (rcu_start_gp+0x34/0x48) from [<c00b0af8>] (rcu_process_callbacks+0x318/0x608)
[<c00b0af8>] (rcu_process_callbacks+0x318/0x608) from [<c004a4b0>] (__do_softirq+0x114/0x2a0)
[<c004a4b0>] (__do_softirq+0x114/0x2a0) from [<c004a704>] (do_softirq+0x6c/0x74)
[<c004a704>] (do_softirq+0x6c/0x74) from [<c004aa1c>] (irq_exit+0xac/0x100)
[<c004aa1c>] (irq_exit+0xac/0x100) from [<c0014b70>] (handle_IRQ+0x54/0xb4)
[<c0014b70>] (handle_IRQ+0x54/0xb4) from [<c0008634>] (omap3_intc_handle_irq+0x60/0x74)
[<c0008634>] (omap3_intc_handle_irq+0x60/0x74) from [<c051d0a4>] (__irq_svc+0x44/0x5c)
Exception stack(0xde05de80 to 0xde05dec8)
de80: 00000001 00000001 00000000 de05b440 c082afac de057ac0 de057ac0 de0443c0
dea0: 00000000 00000000 00000000 00000000 c082afbc de05dec8 c009f2a0 c051c778
dec0: 20000113 ffffffff
[<c051d0a4>] (__irq_svc+0x44/0x5c) from [<c051c778>] (_raw_spin_unlock_irq+0x28/0x2c)
[<c051c778>] (_raw_spin_unlock_irq+0x28/0x2c) from [<c016edb0>] (proc_alloc_inum+0x30/0xa8)
[<c016edb0>] (proc_alloc_inum+0x30/0xa8) from [<c016ee40>] (proc_register+0x18/0x130)
[<c016ee40>] (proc_register+0x18/0x130) from [<c016f054>] (proc_mkdir_data+0x44/0x6c)
[<c016f054>] (proc_mkdir_data+0x44/0x6c) from [<c008eb44>] (register_irq_proc+0x6c/0x128)
[<c008eb44>] (register_irq_proc+0x6c/0x128) from [<c008ed2c>] (init_irq_proc+0x74/0xb0)
[<c008ed2c>] (init_irq_proc+0x74/0xb0) from [<c075ab3c>] (kernel_init_freeable+0x84/0x1c8)
[<c075ab3c>] (kernel_init_freeable+0x84/0x1c8) from [<c0510934>] (kernel_init+0x8/0x150)
[<c0510934>] (kernel_init+0x8/0x150) from [<c0013ce8>] (ret_from_fork+0x14/0x2c)
Code: bad PC value

Fixes: bf18525f "ARM: 7872/1: Support arch_irq_work_raise() via self IPIs"
Reported-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NStephen Boyd <sboyd@codeaurora.org>
Tested-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>