Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This adds preliminary support for the SH7786 CPU subtype.

While this is a dual-core CPU, only UP is supported for now. L2 cache
support is likewise not yet implemented.

More information on this particular CPU subtype is available at:

	http://www.renesas.com/fmwk.jsp?cnt=sh7786_root.jsp&fp=/products/mpumcu/superh_family/sh7780_series/sh7786_group/Signed-off-by: NKuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Acked-by: NGreg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

With the recent entry.S refactoring, the SH-X3 path had a mov.l for a
register to register copy, resulting in:

  AS      arch/sh/kernel/cpu/sh4/../sh3/entry.o
arch/sh/kernel/cpu/sh4/../sh3/entry.S: Assembler messages:
arch/sh/kernel/cpu/sh4/../sh3/entry.S:366: Error: invalid operands for opcode
make[3]: *** [arch/sh/kernel/cpu/sh4/../sh3/entry.o] Error 1

Switch it over to a mov to fix it up.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Update intc tables and platform data to use one linux irq
per maskable interrupt source instead of keeping the one-to-one
mapping between vectors and linux irqs.

This fixes potential irq masking issues for sh7785 hardware
blocks such as SCIF/DMAC/PCIC5/MMCIF/GDTA/FLCTL/GPIO
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Tested-by: NYoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Update intc tables and platform data to use one linux irq
per maskable interrupt source instead of keeping the one-to-one
mapping between vectors and linux irqs.

This fixes potential irq masking issues for sh7780 hardware
blocks such as SCIF/RTC/DMAC/PCIC5/MMCIF/FLCTL/GPIO
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Update intc tables and platform data to use one linux irq
per maskable interrupt source instead of keeping the one-to-one
mapping between vectors and linux irqs.

This fixes potential irq masking issues for sh775x hardware
blocks such as SCI/SCIF/RTC/DMAC/TMU2/REF.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Instead of keeping the single vector -> single linux irq mapping
we extend the intc code to support merging of vectors to a single
linux irq. This helps processors such as sh7750, sh7780 and sh7785
which have more vectors than masking ability. With this patch in
place we can modify the intc tables to use one irq per maskable
irq source. Please note the following:

 - If multiple vectors share the same enum then only the
   first vector will be available as a linux irq.

 - Drivers may need to be rewritten to get pending irq
   source from the hardware block instead of irq number.

This patch together with the sh7785 specific intc tables solves
DMA controller irq issues related to buggy interrupt masking.
Reported-by: NYoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Fix iounmap() of pass-through P4 addresses. Without this patch
iounmap() on the sh7780 rtc area results in a warning message.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Add support for single IRQ hardware to the sh-rtc driver.

This is useful for processors with limited interrupt masking
support such as sh7750 and sh7780. With this patch in place we
can add logic to the intc code that merges all RTC vectors into
a single linux interrupt with proper masking/unmasking support.

Specify a single IRQ in the platform data to use this new shared
IRQ feature. Separate Periodic/Carry/Alarm IRQs are still supported.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Modify the serial console code to wait for the transmit FIFO,
make sure all bits have been put on the wire before returning.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

The SH-3 does not support 'pref'-based prefetching, only SH-2A and SH-4A
parts do. Remove SH-3 from the list.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Prefetch early exception data. There is unused space in our
exception handler cache line anyway, so this is almost free.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

Remove EXPEVT vector from the stack, lookup_exception_vector()
for sh3/sh4/sh4a is already using k2 to get the vector.
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch reworks the sh3/sh4/sh4a register restore code in
the following ways:
 - break out restore_regs() from restore_all()
 - the register saving order is unchanged
 - use restore_regs() in sh_bios_handler and restore_all
 - document the function
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch reworks the sh3/sh4/sh4a register saving code in
the following ways:
 - break out prepare_stack_save_dsp() from handle_exception()
 - break out save_regs() from handle_exception()
 - the register saving order is unchanged
 - align new functions to fit in cache lines
 - separate exception code from interrupt code
 - keep main code flow in a single cache line per exception vector
 - use bsr/rts for regular functions (save pr first)
 - keep data in one shared cache line (exception_data)
 - document the functions
 - tie in the hp6xx code
Signed-off-by: NMagnus Damm <damm@igel.co.jp>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

This patch updates the maple bus to support asynchronous block reads
and writes as well as generally improving the quality of the code and
supporting concurrency (all needed to support the Dreamcast visual
memory unit - a driver will also be posted for that).

Changes in the bus driver necessitate some changes in the two maple bus
input drivers that are currently in mainline.

As well as supporting block reads and writes this code clean up removes
some poor handling of locks, uses an atomic status variable to serialise
access to devices and more robusly handles the general performance
problems of the bus.
Signed-off-by: NAdrian McMenamin <adrian@mcmen.demon.co.uk>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

There was a typo for the overrun bit definition, causing it not to be
handled correctly on SH7785, fix it up.
Signed-off-by: NKuninori Morimoto <morimoto.kuninori@renesas.com>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

The C99 specification states in section 6.11.5:

The placement of a storage-class specifier other than at the
beginning of the declaration specifiers in a declaration is an
obsolescent feature.
Signed-off-by: NTobias Klauser <tklauser@distanz.ch>
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

* git://git.infradead.org/users/cbou/battery-2.6.29:
  pcf50633_charger: Fix typo

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12646

When the temperature exceeds 32767 milli-degrees the temperature overflows
to -32768 millidegrees.  These are bothe well within the -55 - +125 degree
range for the sensor.

Fix overflow in left-shift of a u8.
Signed-off-by: NIan Dall <ian@beware.dropbear.id.au>
Signed-off-by: NEvgeniy Polyakov <zbr@ioremap.net>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix a problem that causes I/O to a disconnected (or partially initialized)
nbd device to hang indefinitely.  To reproduce:

# ioctl NBD_SET_SIZE_BLOCKS /dev/nbd23 514048
# dd if=/dev/nbd23 of=/dev/null bs=4096 count=1

...hangs...

This can also occur when an nbd device loses its nbd-client/server
connection.  Although we clear the queue of any outstanding I/Os after the
client/server connection fails, any additional I/Os that get queued later
will hang.

This bug may also be the problem reported in this bug report:
http://bugzilla.kernel.org/show_bug.cgi?id=12277

Testing would need to be performed to determine if the two issues are the
same.

This problem was introduced by the new request handling thread code ("NBD:
allow nbd to be used locally", 3/2008), which entered into mainline around
2.6.25.

The fix, which is fairly simple, is to restore the check for lo->sock
being NULL in do_nbd_request.  This causes I/O to an uninitialized nbd to
immediately fail with an I/O error, as it did prior to the introduction of
this bug.
Signed-off-by: NPaul Clements <paul.clements@steeleye.com>
Reported-by: NJon Nelson <jnelson-kernel-bugzilla@jamponi.net>
Acked-by: NPavel Machek <pavel@ucw.cz>
Cc: <stable@kernel.org>		[2.6.26.x, 2.6.27.x, 2.6.28.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Christophe Saout reported [in precursor to:
http://marc.info/?l=linux-kernel&m=123209902707347&w=4]:

> Note that I also some a different issue with CONFIG_UNEVICTABLE_LRU.
> Seems like Xen tears down current->mm early on process termination, so
> that __get_user_pages in exit_mmap causes nasty messages when the
> process had any mlocked pages.  (in fact, it somehow manages to get into
> the swapping code and produces a null pointer dereference trying to get
> a swap token)

Jeremy explained:

Yes.  In the normal case under Xen, an in-use pagetable is "pinned",
meaning that it is RO to the kernel, and all updates must go via hypercall
(or writes are trapped and emulated, which is much the same thing).  An
unpinned pagetable is not currently in use by any process, and can be
directly accessed as normal RW pages.

As an optimisation at process exit time, we unpin the pagetable as early
as possible (switching the process to init_mm), so that all the normal
pagetable teardown can happen with direct memory accesses.

This happens in exit_mmap() -> arch_exit_mmap().  The munlocking happens
a few lines below.  The obvious thing to do would be to move
arch_exit_mmap() to below the munlock code, but I think we'd want to
call it even if mm->mmap is NULL, just to be on the safe side.

Thus, this patch:

exit_mmap() needs to unlock any locked vmas before calling arch_exit_mmap,
as the latter may switch the current mm to init_mm, which would cause the
former to fail.
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Christophe Saout <christophe@saout.de>
Cc: Keir Fraser <keir.fraser@eu.citrix.com>
Cc: Christophe Saout <christophe@saout.de>
Cc: Alex Williamson <alex.williamson@hp.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since netmos 9835 with subids 0x1014(IBM):0x0299 is now bound with
serial/8250_pci, because it has no parallel ports and subdevice id isn't
in the expected form, return -ENODEV from probe function.

This is performed in netmos preinit_hook.
Signed-off-by: NJiri Slaby <jirislaby@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit dcf6a79d ("write-back: fix
nr_to_write counter") fixed nr_to_write counter, but didn't set the break
condition properly.

If nr_to_write == 0 after being decremented it will loop one more time
before setting done = 1 and breaking the loop.

[akpm@linux-foundation.org: coding-style fixes]
Cc: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Acked-by: NNick Piggin <npiggin@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With the new system call defines we get this on uml:

arch/um/sys-i386/built-in.o: In function `sys_call_table':
(.rodata+0x308): undefined reference to `sys_sigprocmask'

Reason for this is that uml passes the preprocessor option
-Dsigprocmask=kernel_sigprocmask to gcc when compiling the kernel.
This causes SYSCALL_DEFINE3(sigprocmask, ...) to be expanded to
SYSCALL_DEFINEx(3, kernel_sigprocmask, ...) and finally to a system
call named sys_kernel_sigprocmask.  However sys_sigprocmask is missing
because of this.

To avoid macro expansion for the system call name just concatenate the
name at first define instead of carrying it through severel levels.
This was pointed out by Al Viro.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: NWANG Cong <wangcong@zeuux.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

For a reason that I was unable to understand in three months of debugging,
mount ext2 -o remount stopped working properly when remounting from
regular operation to xip, or the other way around.  According to a git
bisect search, the problem was introduced with the VM_MIXEDMAP/PTE_SPECIAL
rework in the vm:

commit 70688e4d
Author: Nick Piggin <npiggin@suse.de>
Date:   Mon Apr 28 02:13:02 2008 -0700

    xip: support non-struct page backed memory

In the failing scenario, the filesystem is mounted read only via root=
kernel parameter on s390x.  During remount (in rc.sysinit), the inodes of
the bash binary and its libraries are busy and cannot be invalidated (the
bash which is running rc.sysinit resides on subject filesystem).
Afterwards, another bash process (running ifup-eth) recurses into a
subshell, runs dup_mm (via fork).  Some of the mappings in this bash
process were created from inodes that could not be invalidated during
remount.

Both parent and child process crash some time later due to inconsistencies
in their address spaces.  The issue seems to be timing sensitive, various
attempts to recreate it have failed.

This patch refuses to change the xip flag during remount in case some
inodes cannot be invalidated.  This patch keeps users from running into
that issue.

[akpm@linux-foundation.org: cleanup]
Signed-off-by: NCarsten Otte <cotte@de.ibm.com>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Jared Hulbert <jaredeh@gmail.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I enabled all cgroup subsystems when compiling kernel, and then:
 # mount -t cgroup -o net_cls xxx /mnt
 # mkdir /mnt/0

This showed up immediately:
 BUG: MAX_LOCKDEP_SUBCLASSES too low!
 turning off the locking correctness validator.

It's caused by the cgroup hierarchy lock:
	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
		struct cgroup_subsys *ss = subsys[i];
		if (ss->root == root)
			mutex_lock_nested(&ss->hierarchy_mutex, i);
	}

Now we have 9 cgroup subsystems, and the above 'i' for net_cls is 8, but
MAX_LOCKDEP_SUBCLASSES is 8.

This patch uses different lockdep keys for different subsystems.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPaul Menage <menage@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add Li Zefan as co-maintainer.
Acked-by: NPaul Menage <menage@google.com>
Acked-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

With a postfix decrement t will reach -1 rather than 0, so neither the
warning nor the `goto error_out' will occur.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Acked-by: NManuel Lauss <mano@roarinelk.homelinux.net>
Acked-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc processing of SYSCALL wrappers.

The SYSCALL wrapper patches played havoc with kernel-doc for
syscalls.  Syscalls that were scanned for DocBook processing
reported warnings like this one, for sys_tgkill:

Warning(kernel/signal.c:2285): No description found for parameter 'tgkill'
Warning(kernel/signal.c:2285): No description found for parameter 'pid_t'
Warning(kernel/signal.c:2285): No description found for parameter 'int'

because the macro parameters all "look like" function parameters,
although they are not:

/**
 *  sys_tgkill - send signal to one specific thread
 *  @tgid: the thread group ID of the thread
 *  @pid: the PID of the thread
 *  @sig: signal to be sent
 *
 *  This syscall also checks the @tgid and returns -ESRCH even if the PID
 *  exists but it's not belonging to the target process anymore. This
 *  method solves the problem of threads exiting and PIDs getting reused.
 */
SYSCALL_DEFINE3(tgkill, pid_t, tgid, pid_t, pid, int, sig)
{
...

This patch special-cases the handling SYSCALL_DEFINE* function
prototypes by expanding them to
	long sys_foobar(type1 arg1, type1 arg2, ...)
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc-nano-HOWTO.txt to use */ as the ending marker in kernel-doc
examples and state that */ is the preferred ending marker.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Reported-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

page_cgroup's page allocation at init/memory hotplug uses kmalloc() and
vmalloc(). If kmalloc() failes, vmalloc() is used.

This is because vmalloc() is very limited resource on 32bit systems.
We want to use kmalloc() first.

But in this kind of call, __GFP_NOWARN should be specified.
Reported-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NUwe Kleine-Koenig <ukleinek@strlen.de>
Signed-off-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Update my email address.
Signed-off-by: NMarcel Selhorst <m.selhorst@sirrix.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When I tested following program, I found that the mlocked counter
is strange.  It cannot free some mlocked pages.

It is because try_to_unmap_file() doesn't check real
page mappings in vmas.

That is because the goal of an address_space for a file is to find all
processes into which the file's specific interval is mapped.  It is
related to the file's interval, not to pages.

Even if the page isn't really mapped by the vma, it returns SWAP_MLOCK
since the vma has VM_LOCKED, then calls try_to_mlock_page.  After this the
mlocked counter is increased again.

COWed anon page in a file-backed vma could be a such case.  This patch
resolves it.

-- my test program --

int main()
{
       mlockall(MCL_CURRENT);
       return 0;
}

-- before --

root@barrios-target-linux:~# cat /proc/meminfo | egrep 'Mlo|Unev'
Unevictable:           0 kB
Mlocked:               0 kB

-- after --

root@barrios-target-linux:~# cat /proc/meminfo | egrep 'Mlo|Unev'
Unevictable:           8 kB
Mlocked:               8 kB
Signed-off-by: NMinChan Kim <minchan.kim@gmail.com>
Acked-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: NKOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit c87591b7.

Since journal_start_commit() is now fixed to return 1 when we started a
transaction commit, there's some transaction waiting to be committed or
there's a transaction already committing, we don't need to call
ext3_force_commit() in ext3_sync_fs().  Furthermore ext3_force_commit()
can unnecessarily create sync transaction which is expensive so it's
worthwhile to remove it when we can.

Cc: Eric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

journal_start_commit() returns 1 if either a transaction is committing or
the function has queued a transaction commit.  But it returns 0 if we
raced with somebody queueing the transaction commit as well.  This
resulted in ext3_sync_fs() not functioning correctly (description from
Arthur Jones): In the case of a data=ordered umount with pending long
symlinks which are delayed due to a long list of other I/O on the backing
block device, this causes the buffer associated with the long symlinks to
not be moved to the inode dirty list in the second phase of fsync_super.
Then, before they can be dirtied again, kjournald exits, seeing the UMOUNT
flag and the dirty pages are never written to the backing block device,
causing long symlink corruption and exposing new or previously freed block
data to userspace.

This can be reproduced with a script created by Eric Sandeen
<sandeen@redhat.com>:

        #!/bin/bash

        umount /mnt/test2
        mount /dev/sdb4 /mnt/test2
        rm -f /mnt/test2/*
        dd if=/dev/zero of=/mnt/test2/bigfile bs=1M count=512
        touch /mnt/test2/thisisveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryverylongfilename
        ln -s /mnt/test2/thisisveryveryveryveryveryveryveryveryveryveryveryveryveryveryveryverylongfilename
        /mnt/test2/link
        umount /mnt/test2
        mount /dev/sdb4 /mnt/test2
        ls /mnt/test2/

This patch fixes journal_start_commit() to always return 1 when there's
a transaction committing or queued for commit.

Cc: Eric Sandeen <sandeen@redhat.com>
Cc: Mike Snitzer <snitzer@gmail.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We need to pass an unsigned long as the minimum, because it gets casted
to an unsigned long in the sysctl handler. If we pass an int, we'll
access four more bytes on 64bit arches, resulting in a random minimum
value.

[rientjes@google.com: fix type of `old_bytes']
Signed-off-by: NSven Wegener <sven.wegener@stealer.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>