The ns_cgroup is a control group interacting with the namespaces.  When a
new namespace is created, a corresponding cgroup is automatically created
too.  The cgroup name is the pid of the process who did 'unshare' or the
child of 'clone'.

This cgroup is tied with the namespace because it prevents a process to
escape the control group and use the post_clone callback, so the child
cgroup inherits the values of the parent cgroup.

Unfortunately, the more we use this cgroup and the more we are facing
problems with it:

(1) when a process unshares, the cgroup name may conflict with a
    previous cgroup with the same pid, so unshare or clone return -EEXIST

(2) the cgroup creation is out of control because there may have an
    application creating several namespaces where the system will
    automatically create several cgroups in his back and let them on the
    cgroupfs (eg.  a vrf based on the network namespace).

(3) the mix of (1) and (2) force an administrator to regularly check
    and clean these cgroups.

This patchset removes the ns_cgroup by adding a new flag to the cgroup and
the cgroupfs mount option.  It enables the copy of the parent cgroup when
a child cgroup is created.  We can then safely remove the ns_cgroup as
this flag brings a compatibility.  We have now to manually create and add
the task to a cgroup, which is consistent with the cgroup framework.

This patch:

Sent as an answer to a previous thread around the ns_cgroup.

https://lists.linux-foundation.org/pipermail/containers/2009-June/018627.html

It adds a control file 'clone_children' for a cgroup.  This control file
is a boolean specifying if the child cgroup should be a clone of the
parent cgroup or not.  The default value is 'false'.

This flag makes the child cgroup to call the post_clone callback of all
the subsystem, if it is available.

At present, the cpuset is the only one which had implemented the
post_clone callback.

The option can be set at mount time by specifying the 'clone_children'
mount option.
Signed-off-by: NDaniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: NSerge E. Hallyn <serge.hallyn@canonical.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: NPaul Menage <menage@google.com>
Reviewed-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Jamal Hadi Salim <hadi@cyberus.ca>
Cc: Matt Helsley <matthltc@us.ibm.com>
Acked-by: NBalbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There are 4 state transitions possible for a freezer.  Only FREEZING ->
FROZEN transaction is done lazily.  This patch allows update_freezer_state
only to perform this transaction and renames the function to
update_if_frozen.

Moreover is_task_frozen_enough function is removed and its every occurence
is replaced with frozen().  Therefore for a group to become FROZEN every
task must be frozen.

The previous version could trigger a following bug: When cgroup is in the
process of freezing (but none of its tasks are frozen yet),
update_freezer_state() (called from freezer_read or freezer_write) would
incorrectly report that a group is 'THAWED' (because nfrozen = 0),
allowing the transaction FREEZING -> THAWED without writing anything to
'freezer.state'.  This is incorrect according to the documentation.  This
could result in a 'THAWED' cgroup with frozen tasks inside.

A code to reproduce this bug is available here:
http://pentium.hopto.org/~thinred/repos/linux-misc/freezer_bug2.c

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NTomasz Buchert <tomasz.buchert@inria.fr>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It is possible to move a task from its cgroup even if this group is
'FREEZING'.  This results in a nasty bug - the moved task will become
frozen OUTSIDE its original cgroup and will remain in a permanent 'D'
state.

This patch allows to migrate the task only between THAWED cgroups.

This behavior was observed and easily reproduced on a single core laptop.
Notice that reproducibility depends highly on the machine used.  Program
and instructions how to reproduce the bug can be fetched from:
http://pentium.hopto.org/~thinred/repos/linux-misc/freezer_bug.cSigned-off-by: NTomasz Buchert <tomasz.buchert@inria.fr>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The root freezer_state is always CGROUP_THAWED so we can remove the
special case from the code.  The test itself can be handy and is extracted
to static function.
Signed-off-by: NTomasz Buchert <tomasz.buchert@inria.fr>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When dirty_ratio or dirty_bytes is written the other parameter is disabled
and set to 0 (in dirty_bytes_handler() / dirty_ratio_handler()).

We do the same for dirty_background_ratio and dirty_background_bytes.

However, in the sysctl documentation, we say that the counterpart becomes
a function of the old value, that is not correct.

Clarify the documentation reporting the actual behaviour.
Reviewed-by: NGreg Thelen <gthelen@google.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NAndrea Righi <arighi@develer.com>
Cc: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If a CD has both Rock Ridge and Joliet extensions and the ISO root
directory is empty, no files are visible.  Disable Rock Ridge extensions
in this case and use Joliet root directory instead.
Signed-off-by: NOndrej Zary <linux@rainbow-software.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Guenter Roeck <guenter.roeck@ericsson.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Untested, but looks like an obvious typo to me.
Signed-off-by: NNicolas Kaiser <nikai@nikai.net>
Cc: Tomi Valkeinen <tomi.valkeinen@nokia.com>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This code is preceded by a call to framebuffer_alloc, which allocates
memory, so this memory should be freed before leaving the function in an
error case.  out_release_framebuffer just frees the frame buffer and
returns.

A simplified version of the semantic match that finds this problem is:
(http://coccinelle.lip6.fr/)

// <smpl>
@r exists@
local idexpression x;
expression E;
identifier f1;
iterator I;
@@

x = framebuffer_alloc(...);
<... when != x
     when != true (x == NULL || ...)
     when != if (...) { <+...x...+> }
     when != I (...) { <+...x...+> }
(
 x == NULL
|
 x == E
|
 x->f1
)
...>
* return ...;
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fb_{read,write} access the framebuffer using lots of fb_{read,write}l's
but don't check that the file position is aligned which can cause problems
on some architectures which do not support unaligned accesses.

Since the operations are essentially memcpy_{from,to}io, new
fb_memcpy_{from,to}fb macros have been defined and these are used instead.

For Sparc, fb_{read,write} macros use sbus_{read,write}, so this defines
new sbus_memcpy_{from,to}io functions the same as memcpy_{from,to}io but
using sbus_{read,write}b instead of {read,write}b.
Signed-off-by: NJames Hogan <james@albanarts.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NFlorian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change a few lines of indentation to tabs.
Signed-off-by: NJames Hogan <james@albanarts.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The function has an unsigned return type, but returns a negative constant
to indicate an error condition.  The result of calling the function is
only tested by comparison to 0, and thus unsigned is not needed and can be
dropped from the return type.

A sematic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@exists@
identifier f;
constant C;
@@

 unsigned f(...)
 { <+...
*  return -C;
 ...+> }
// </smpl>
Signed-off-by: NJulia Lawall <julia@diku.dk>
Cc: Petr Vandrovec <vandrove@vc.cvut.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I tested savagefb on 3 different Savage 4 cards:
Diamond Stealth III S520
Number Nine SR9
Datapath Horizon 2S (two savage chips on a PCI card)

it worked except the DDC which did not work on any of them.

Looking at the BIOS code, it does not use MMIO register 0xff20 but CRT
register 0xa0 or 0xb1 - depending on the chip revision and something in
register 0xa6.  With this patch, DDC works fine on all 3 cards (even on
the second head of Horizon 2S - although it does not display anything as
it's misconfigured because of missing BIOS).
Signed-off-by: NOndrej Zary <linux@rainbow-software.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The CONFIG_FB_MATROX_G ifdef isn't necessary at this point, because it is
checked in an outer ifdef level already and has no effect here.
Signed-off-by: NChristian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
Acked-by: NJean Delvare <khali@linux-fr.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In this case the logic is very similar but the IRQs are not exposed and
the device is not picked up via PCI

Based on a separate internal whitney point driver by Yin Kangkai.
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Cc: Yin Kangkai <kangkai.yin@intel.com>
Cc: Alek Du <alek.du@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Deweird this driver.

Cc: Alek Du <alek.du@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Topcliff PCH is the platform controller hub that is going to be used in
Intel's upcoming general embedded platform.  All IO peripherals in
Topcliff PCH are actually devices sitting on AMBA bus.  Topcliff PCH has
GPIO I/F.  Using this I/F, it is able to access system devices connected
to GPIO.

[akpm@linux-foundation.org: ese DEFINE_PCI_DEVICE_TABLE (per Joe Perches)]
Signed-off-by: NTomoya MORINAGA <tomoya-linux@dsn.okisemi.com>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Rabin Vincent <rabin.vincent@stericsson.com>
Cc: Samuel Ortiz <sameo@linux.intel.com>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Tomoya MORINAGA <morinaga526@dsn.okisemi.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some ADP5588 functions take a pointer to an i2c_client, but if the i2c
header doesn't happen to be included first, we hit the standard "struct
declared inside parameter list" warnings from gcc.  So add a simple
forward decl of the i2c_client struct.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Common code interprets this as a signed value (a negative value is used to
request dynamic ID allocation), so make sure the platform data has proper
types to support that.
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Implement irq_chip functionality on ADP5588/5587 GPIO expanders.  Only
level sensitive interrupts are supported.  Interrupts provided by this
irq_chip must be requested using request_threaded_irq().
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add support for generic 74x164 serial-in/parallel-out 8-bits shift
register.  This driver can be used as a GPIO output expander.

[akpm@linux-foundation.org: remove unused local `refresh']
Signed-off-by: NMiguel Gaio <miguel.gaio@efixo.com>
Signed-off-by: NJuhos Gabor <juhosg@openwrt.org>
Signed-off-by: NFlorian Fainelli <florian@openwrt.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some versions of the hardware can trash the IER register if simultaneous
interrupts occur.  This patch works around it by using a local copy of the
register and restoring it after every interrupt.
Signed-off-by: NTomas Hallenberg <tomas.hallenberg@pelagicore.com>
Acked-by: NRichard Röjfors <richard.rojfors@pelagicore.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 7444a72e ("gpiolib: allow user-selection")
removed HAVE_GPIO_LIB Kconfig symbol, but the header file still uses the
name [to confuse readers wrt #ifdef/#else/#endif location].

The real Kconfig symbol nowadays is CONFIG_GPIOLIB.
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
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>

The basic GPIO controllers may be found in various on-board FPGA and ASIC
solutions that are used to control board's switches, LEDs, chip-selects,
Ethernet/USB PHY power, etc.

These controllers may not provide any means of pin setup
(in/out/open drain).

The driver supports:
- 8/16/32/64 bits registers;
- GPIO controllers with clear/set registers;
- GPIO controllers with a single "data" register;
- Big endian bits/GPIOs ordering (mostly used on PowerPC).
Signed-off-by: NAnton Vorontsov <cbouatmailru@gmail.com>
Reviewed-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Cc: David Brownell <david-b@pacbell.net>
Cc: Samuel Ortiz <sameo@linux.intel.com>,
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add the "alarm" function to the jz4740 RTC.  Interrupts will now be raised
when the "alarm" time is reached.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NPaul Cercueil <paul@crapouillou.net>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Paul Gortmaker <p_gortmaker@yahoo.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The DS3232 RTC driver only has the tick function.  Add an alarm function
so the driver is complete.
Signed-off-by: NLan Chunhe-B25806 <b25806@freescale.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add "rtc_valid_tm" in s3c_rtc_gettime() as per Wan ZongShun's suggestion.
Suggested-by: NWan ZongShun <mcuos.com@gmail.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change RTC initialization method in probe().  The 'rtc_valid_tm(tm)' can
check whether RTC BCD is valid or not.  And change the method of checking
because the previous method cannot validate RTC BCD registers properly.
Signed-off-by: NChanghwan Youn <chaos.youn@samsung.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix debug message format.
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Acked-by: NBen Dooks <ben-linux@fluff.org>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The alarm_irq_enable function should be implemented to support RTC alarm.
And fix tabs instead of white space around the proc field.
Signed-off-by: NChanghwan Youn <chaos.youn@samsung.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Acked-by: NBen Dooks <ben-linux@fluff.org>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Current s3c_rtc_getalarm() sets missing field of alarm time with 0xff.
But this value should be -1 according to drivers/rtc/interface.c.
Signed-off-by: NChanghwan Youn <chaos.youn@samsung.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Acked-by: NBen Dooks <ben-linux@fluff.org>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

S3C2410_RTCCON of TYPE_S3C64XX RTC should be read/written by readw and
writew, because TYPE_S3C64XX RTC uses bit 8 and 9.  And TYPE_S3C2410 RTC
also can access it by readw and writew.

[atul.dahiya@samsung.com: tested on smdk2416]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NChanghwan Youn <chaos.youn@samsung.com>
Signed-off-by: NKukjin Kim <kgene.kim@samsung.com>
Tested-by: NAtul Dahiya <atul.dahiya@samsung.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The rtc-omap driver currently hardcodes the RTC wakeup capability to be
"not capable".  While this seems to be true for existing OMAP1 boards
which are not wired for this, the DA850/OMAP-L138 SoC, the RTC can always
be wake up source from its "deep sleep" mode.

This patch lets the wakeup capability be set from platform data and does
not override the setting from the driver.  For DA850/OMAP-L138, this is
done from arch/arm/mach-davinci/devices-da8xx.c:da8xx_register_rtc()

Note that this patch does not change the behavior on any existing OMAP1
board since the platform device registration sets the wakeup capability to
0 by default.
Signed-off-by: NSekhar Nori <nsekhar@ti.com>
Signed-off-by: NKevin Hilman <khilman@deeprootsystems.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
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>

If device_register() fails then call put_device().  See comment to
device_register.
Signed-off-by: NVasiliy Kulikov <segooon@gmail.com>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The rest of the driver had debug markings already.  This also standardizes
the usage of "dev" a bit.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

By unifying the RTC_ISTAT clearing steps, we shrink the interrupt handler
and avoid multiple writes to the hardware registers.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>
Acked-by: NAlessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add an RTC driver for the built-in RTC in the LPC32XX SoC.  This patch
includes updates from the initial review comments and updates from the v3
review.
Signed-off-by: NKevin Wells <wellsk40@gmail.com>
Signed-off-by: NDurgesh Pattamatta <durgesh.pattamatta@nxp.com>
Reviewed-by: NWolfram Sang <w.sang@pengutronix.de>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When all VT's are in use, VT_OPENQRY casts -1 to unsigned char before
returning it to userspace as an int.  VT255 is not the next available
console.
Signed-off-by: NGraham Gower <graham.gower@gmail.com>
Cc: Greg KH <greg@kroah.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Put basic system information in the dmesg log.  There are lots of dmesg
logs on the web, and it would be useful if they contained this information
for debugging platform problems.  "BOARD/PRODUCT" format copied from
show_regs_common(), which is used in the oops path.
Signed-off-by: NBjorn Helgaas <bjorn.helgaas@hp.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: NChris Metcalf <cmetcalf@tilera.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Christoph reported a nice splat which illustrated a race in the new stack
based kmap_atomic implementation.

The problem is that we pop our stack slot before we're completely done
resetting its state -- in particular clearing the PTE (sometimes that's
CONFIG_DEBUG_HIGHMEM).  If an interrupt happens before we actually clear
the PTE used for the last slot, that interrupt can reuse the slot in a
dirty state, which triggers a BUG in kmap_atomic().

Fix this by introducing kmap_atomic_idx() which reports the current slot
index without actually releasing it and use that to find the PTE and delay
the _pop() until after we're completely done.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: NChristoph Hellwig <hch@infradead.org>
Acked-by: NRik van Riel <riel@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>