There is a bug in error path of mem_cgroup_move_parent.
Extra refcnt got from try_charge should be dropped, and usages incremented
by try_charge should be decremented in both error paths:
A: failure at get_page_unless_zero
B: failure at isolate_lru_page
This bug makes this parent directory unremovable.
In case of A, rmdir doesn't return, because res.usage doesn't go down to 0
at mem_cgroup_force_empty even after all the pc in lru are removed.
In case of B, rmdir fails and returns -EBUSY, because it has extra ref
counts even after res.usage goes down to 0.
Signed-off-by: Daisuke Nishimura <nishimura@mxp.nes.nec.co.jp>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The light sensors ALV0 and ALV1 on newer MacBooks (early 2008 and later)
changed to report 10 bytes instead the earlier 6, and the sensor encoding
subsequently changed. As a result, the reported light sensors readings
are much too low.
Via experiments leading up to this patch, it seems only the ALV0 is
reporting data, and the most useful value therein is a 10-bit big-endian
value at offset 6. This suggests that a new protocol was added as a
backward-compatible replacement on top of the old one.
This patch makes applesmc report the improved light sensor reading for the
new machines, on a scale in conformance with earlier ones.
Signed-off-by: Alex Murray <murray.alex@gmail.com>
Signed-off-by: Henrik Rydberg <rydberg@euromail.se>
Cc: Nicolas Boichat <nicolas@boichat.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In the general use case struct seq_operations should be a const object.
Check for and warn where it is not.
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should not be continuing a braced section with an if, for example:
if (...) {
} if (...) {
}
Detect this and suggest adding a newline.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we allow return to have surrounding parentheses when containing
comparison operators we are not correctly handling the case where the
values contain array sufffixes. Squash them.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We should not be complaining about the prefix spacing for types and casts.
We are triggering here because the check for spacing between '*'s is
overly loose. Tighten this up.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If the #if opening statement is not in the context then the context stack
can be empty. Handle this by ensuring there is always a blank entry in
the stack.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Tested-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Two nbd-clients at same time are bad idea, and cause WARN_ON from nbd in
2.6.28-rc7 from sysfs_add_one. This simply prevents that from happening.
To reproduce:
cat /dev/zero | head -c 10000000 > /tmp/delme.fstest.fs
nbd-server 9100 -l /anyone.can.connect > /tmp/delme.fstest.fs &
sleep 1
nbd-client localhost 9100 /dev/nd0 &
nbd-client localhost 9100 /dev/nd0 &
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the standard magic.h for btrfs and squashfs.
Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Now that people are using freezer for non-suspend/hibernation stuff, it
should have separate maintainers entry so that it is easier to find.
Signed-off-by: Pavel Machek <pavel@suse.cz>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix __request_region() parameter kernel-doc notation and parameter name:
Warning(linux-2.6.28-git10//kernel/resource.c:627): No description found for parameter 'flags'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix jbd header file kernel-doc notation:
Warning(linux-2.6.28-git13//include/linux/jbd.h:823): No description found for parameter 'j_average_commit_time'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When no option is passed to getdelays it just hangs, waiting
for a reply which will never come.
This patch prints usage() when no output marker is specified.
Signed-off-by: Marcus Meissner <meissner@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
idr_get_new_above() and ida_get_new_above() return an id in the range of
@staring_id ... 0x7fffffff, not 0 ... 0x7fffffff.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- move CONFIG_PROC_PID_CPUSET into cgroup menu
- move MM_OWNER to the bottom for better menu indent
- fix typos
- use tabs not spaces
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Acked-by: Paul Menage <menage@google.com>
Acked-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Enable ring indicator interrupt.
- Remove vendor specific CVS version tags.
Signed-off-by: Paul Fulghum <paulkf@microgate.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After XPC has been up and running on multiple partitions for any length of
time, if XPC on one of the partitions is stopped and restarted (either by
a rmmod/insmod or a system restart), it is possible for the XPCs running
on the other partitions to falsely detect a lack of heartbeat from the XPC
that was just restarted. This false detection will occur if the restarted
XPC comes up within the five-seconds preceding one of the other XPC's
heartbeat check (which occurs once every twenty seconds).
The detection of no heartbeat results in the detecting XPC deactivating
from the just restarted XPC. The only remedy is to restart one of the
XPCs and hope that one doesn't hit this five-second window on any of the
other partitions.
Signed-off-by: Dean Nelson <dcn@sgi.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A triggering RTC alarm should be able to power on a device that has been
powered off. This patch enables that on twl4030 by not masking the alarm
interrupt at shutdown.
Signed-off-by: Matti Halme <matti.halme@nokia.com>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Acked-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Samuel Ortiz <sameo@openedhand.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix these build errors:
CC drivers/rtc/rtc-pxa.o
drivers/rtc/rtc-pxa.c: In function `pxa_rtc_init':
drivers/rtc/rtc-pxa.c:472: error: implicit declaration of function `cpu_is_pxa27x'
drivers/rtc/rtc-pxa.c:472: error: implicit declaration of function `cpu_is_pxa3xx'
Signed-off-by: Antonio Ospite <ao2@openezx.org>
Signed-off-by: Alessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add an explanitory comment as to why we modify the kernel console loglevel
rather than simply moving sysrq messages to KERN_EMERG level.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Document the interactions between loglevel and the sysrq output. Also
document how to work round it should output be required on the console.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Martin Mares <mj@ucw.cz>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
git is maintaining the last update time much more accuratly than the
internal update time. Remove it.
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
i5400 EDAC driver were added upstream by those changesets:
- 920c8df6ac "edac: driver for i5400 MCH (Seaburg)"
- 8375d4909a "edac: driver for i5400 MCH (update)"
Update MAINTAINERS entry for this file to correspond to the driver
maintainer.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Ben Woodard <woodard@redhat.com>
Cc: Doug Thompson <norsk5@yahoo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On alpha, we have to map some stuff in the VMALLOC space very early in the
boot process (to make SRM console callbacks work and so on, see
arch/alpha/mm/init.c). For old VM allocator, we just manually placed a
vm_struct onto the global vmlist and this worked for ages.
Unfortunately, the new allocator isn't aware of this, so it constantly
tries to allocate the VM space which is already in use, making vmalloc on
alpha defunct.
This patch forces KVA to import vmlist entries on init.
[akpm@linux-foundation.org: remove unneeded check (per Johannes)]
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Nick Piggin <npiggin@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Force fb_var_screeninfo color format on all Blackfin Framebuffer Drivers.
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Cc: Mike Frysinger <vapier.adi@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A number of drivers in drivers/gpio return -ENODEV when confronted with
missing setup parameters such as the platform data. However, returning
-ENODEV causes the driver layer to silently ignore the driver as it
assumes the probe did not find anything and was only speculative.
To make life easier to discern why a driver is not being attached, change
to returning -EINVAL, which is a better description of the fact that the
driver data was not valid.
Also add a set of dev_dbg() statements to the error paths to provide an
better explanation of the error as there may be more that one point in the
driver.
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For some reason I have to slowdown clock to touchscreen device.
In atmel_spi_setup() there is comment that max_speed_hz == 0 means as slow
as possible and divider is set to maximum value. But in
atmel_spi_transfer() function is check against not zero max_speed_hz with
EINVAL returned.
Probably driver should setup divider for each transfer based on
transfer->speed_hz value, but I think that would be not necessary overhead
as all used devices have constant clock.
Below patch works fine for me.
Signed-off-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix the following problem, related to hardware flow control (CTS/RTS):
Transmitting while CTS line is asserted in DMA mode, due to not checking
for tx-stopped condition.
We found these problems while testing the UARTs with hardware
flow-control.
Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: "Andrew Victor" <avictor.za@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Update Documentation/sysctl/vm.txt and Documentation/filesystems/proc.txt.
More specifically, the section on /proc/sys/vm in
Documentation/filesystems/proc.txt was removed and a link to
Documentation/sysctl/vm.txt added.
Most of the verbiage from proc.txt was simply moved in vm.txt, with new
addtional text for "swappiness" and "stat_interval".
Signed-off-by: Peter W Morreale <pmorreale@novell.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This reverts commit 58dab916df, which
makes my Nehalem come to a nasty crawling almost-halt. It looks like it
turns off caching of regular kernel RAM, with the understandable
slowdown of a few orders of magnitude as a result.
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Peter Anvin <hpa@zytor.com>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6:
[IA64] SN specific version of dma_get_required_mask()
[IA64] generic_defconfig: Enable SATA_VITESSE
[IA64] dump stack on kernel unaligned warnings
[IA64] Turn on CONFIG_HAVE_UNSTABLE_CLOCK
[IA64] Update to use account_{steal,idle}_ticks
Update employer's care-of address in CREDITS file, and remove references
to some _very_ old stuff I'd forgotten I'd ever done.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6:
ALSA: hda - Fix invalid amp value for STAC925x
ASoC: Fix the power update function for snd_soc_dapm_value_mux
sound: virtuoso: do not overwrite EEPROM on Xonar D2/D2X
ALSA: hda - Fix HP dv5 mic input
ALSA: hda - Fix missing initialization of NID 0x0e for STAC925x
ALSA: USB quirk for Logitech Quickcam Pro 9000 name
ALSA: hda - Fix stac92hd83xxx_amp_nids[]
ALSA: hda - Add automatic model setting for Samsung Q45
ALSA: hda - Don't reset HP pinctl in patch_sigmatel.c
ALSA: hda: stac92hd8xxx amp mixers
ALSA: hda - Fix silent headphone output on Panasonic CF-74
ALSA: hda - Update model descriptions in patch_sigmatel.c
ALSA: hda - Use queue_delayed_work()
ALSA: hda - Add quirk for another HP dv5
ALSA: hda - Add support of NVidia MCP78 HDMI
ALSA: hda - Fix a typo
ALSA: hda - More fixes on Gateway entries
ALSA: patch_sigmatel: Add missing Gateway entries and autodetection
ALSA: hda - Add a new function to seek for a codec ID
This patch is for Alan Cox as it related to the tty layer.
Hopefully the hso driver is again relatively stable with this fix.
Signed-off-by: Denis Joseph Barrow <D.Barow@option.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The HSO changes for kref introduced a recursive spinlock take. All
functions which call put_rxbuf_data already have serial->serial_lock
grabbed.
[Comment to code added-AC]
Signed-off-by: Denis Joseph Barrow <D.Barrow@option.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit 4a90f09b20 added kref stuff to
ftdi_sio, but missed tty_kref_put at one exit point in
ftdi_process_read.
Signed-off-by: Jim Paris <jim@jtan.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This was not implemented correctly for the pnx8xxx_uart driver.
[From further discussion:
Correct, you can look to it as two separate bugs:
a) the next character is not ignored while it should;
b) the status bits 31-8 are copied to the 'ch' variable while they shouldn't.
Both bugs prevent correct break signal handling (and therefore correct
behaviour of the magic SysRq key). Bug b didn't cause too much trouble
earlier because in most situations the status bits are all zero; for
this case they unfortunately aren't.
]
Signed-off-by: Mischa Jonker <mischa.jonker@nxp.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add SupraExpress 336i PnP Voice Modem
Tested and working with the following device: (output from lspnp -v)
01:01.00 SUP1381 (unknown)
state = active
io 0x2f8-0x2ff
irq 3
Signed-off-by: Daniel Gagnon <daniel.gagnon@yahoo.com>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Most of netmos 9835 hardware is handled by parport-serial. IBM introduces
a device which doesn't have any parallel ports and have screwed subdevice
PCI id (not corresponding to port numbers).
Handle this device (9710:9835 1014:0299) properly.
Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If you issue an ioctl to flush a tty as the line discipline is changing or
otherwise unplugged you can get a crash. The bug is very old but the rest
of the BKL lock dropping and some very "good" luck on Ingo's part caught
an example.
Use the correct ldisc_ref form so that we wait for the ldisc change to
complete and then flush
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Create a platform specific version of dma_get_required_mask()
for ia64 SN Altix. All SN Altix platforms support 64 bit DMA
addressing regardless of the size of system memory.
Create an ia64 machvec for dma_get_required_mask, with the
SN version unconditionally returning DMA_64BIT_MASK.
Signed-off-by: John Keller <jpk@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
CONFIG_SATA_VITESSE=y was not added to generic_defconfig when
sn2_defconfig was removed. SGI Altix systems that use an IO10
base IO card to drive the root device are unable to boot without
the Vitesse controller.
Signed-off-by: Brent Casavant <bcasavan@sgi.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Jes Sorensen <jes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Often the cause of kernel unaligned access warnings is not
obvious from just the ip displayed in the warning. This adds
the option via proc to dump the stack in addition to the warning.
The default is off (just display the 1 line warning). To enable
the stack to be shown: echo 1 > /proc/sys/kernel/unaligned-dump-stack
Signed-off-by: Doug Chapman <doug.chapman@hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
sched_clock() on ia64 is based on ar.itc, so is never
completely synchronized between cpus. On some platforms
(e.g. certain models of SGI Altix) it may be running at
radically different frequencies.
Based on a patch from Dimitri Sivanich which set this
just for SN2 && GENERIC kernels ... it is needed for
all ia64 machines.
Signed-off-by: Tony Luck <tony.luck@intel.com>
This patch fixes the following errors caused by
79741dd357 which changed
the prototypes of account_steal_time() and account_idle_time().
> CC arch/ia64/xen/time.o
> arch/ia64/xen/time.c: In function 'consider_steal_time':
> arch/ia64/xen/time.c:132: warning: passing argument 1 of 'account_steal_time' makes integer from pointer without a cast
> arch/ia64/xen/time.c:132: error: too many arguments to function 'account_steal_time'
> arch/ia64/xen/time.c:133: warning: passing argument 1 of 'account_steal_time' makes integer from pointer without a cast
> arch/ia64/xen/time.c:133: error: too many arguments to function 'account_steal_time'
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Daisuke Nishimura
Alex Murray
Andy Whitcroft
Pavel Machek
Qinghuang Feng
Randy Dunlap
Marcus Meissner
Li Zefan
Paul Fulghum
Dean Nelson
Matti Halme
Antonio Ospite
Alessandro Zummo
Mauro Carvalho Chehab
Ivan Kokshaysky
Michael Hennerich
Ben Dooks
Stanislaw Gruszka
Itai Levi
Peter W Morreale
Linus Torvalds
David Woodhouse
Denis Joseph Barrow
Denis Joseph Barrow
Alan Cox
Jim Paris
Mischa Jonker
Daniel Gagnon
Jiri Slaby
John Keller
Brent Casavant
Doug Chapman
Tony Luck
Isaku Yamahata