Add information about the mapping state of the direct mapping to
/proc/meminfo. I chose /proc/meminfo because that is where all the other
memory statistics are too and it is a generally useful metric even
outside debugging situations. A lot of split kernel pages means the
kernel will run slower.

This way we can see how many large pages are really used for it and how
many are split.

Useful for general insight into the kernel.

v2: Add hotplug locking to 64bit to plug a very obscure theoretical race.
    32bit doesn't need it because it doesn't support hotadd for lowmem.
    Fix some typos
v3: Rename dpages_cnt
    Add CONFIG ifdef for count update as requested by tglx
    Expand description
v4: Fix stupid bugs added in v3
    Move update_page_count to pageattr.c
Signed-off-by: NAndi Kleen <andi@firstfloor.org>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* 'kvm-updates-2.6.26' of git://git.kernel.org/pub/scm/linux/kernel/git/avi/kvm:
  KVM: IOAPIC: Fix level-triggered irq injection hang
  x86: KVM guest: Add memory clobber to hypercalls

The pxa27x DMA controller defaults to 64-bit alignment. This caused
the SCR reads to fail (and, depending on card type, error out) when
card->raw_scr was not aligned on a 8-byte boundary.

For performance reasons all scatter-gather addresses passed to
pxamci_request should be aligned on 8-byte boundaries, but if
this can't be guaranteed, byte aligned DMA transfers in the
have to be enabled in the controller to get correct behaviour.
Signed-off-by: NPhilipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit e8721549.

Andrey Borzenkov reports that it resulted in a totally hung machine for
him when loading the OHCI driver.  Extensive netconsole capture with
SysRq output shows that modprobe gets stuck in ohci_hub_status_data()
when probing and enabling the OHCI controller, see for example

	http://lkml.org/lkml/2008/7/5/236

for an analysis.

The problem appears to be an interrupt flood triggered by the commit
that gets reverted, and Andrey confirmed that the revert makes things
work for him again.
Reported-and-tested-by: NAndrey Borzenkov <arvidjaar@mail.ru>
Acked-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NDavid Brownell <david-b@pacbell.net>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The "remote_irr" variable is used to indicate an interrupt
which has been received by the LAPIC, but not acked.

In our EOI handler, we unset remote_irr and re-inject the
interrupt if the interrupt line is still asserted.

However, we do not set remote_irr here, leading to a
situation where if kvm_ioapic_set_irq() is called, then we go
ahead and call ioapic_service(). This means that IRR is
re-asserted even though the interrupt is currently in service
(i.e. LAPIC IRR is cleared and ISR/TMR set)

The issue with this is that when the currently executing
interrupt handler finishes and writes LAPIC EOI, then TMR is
unset and EOI sent to the IOAPIC. Since IRR is now asserted,
but TMR is not, then when the second interrupt is handled,
no EOI is sent and if there is any pending interrupt, it is
not re-injected.

This fixes a hang only seen while running mke2fs -j on an
8Gb virtio disk backed by a fully sparse raw file, with
aliguori "avoid fragmented virtio-blk transfers by copying"
changes.
Signed-off-by: NMark McLoughlin <markmc@redhat.com>
Acked-by: NMarcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Hypercalls can modify arbitrary regions of memory.  Make sure to indicate this
in the clobber list.  This fixes a hang when using KVM_GUEST kernel built with
GCC 4.3.0.

This was originally spotted and analyzed by Marcelo.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAvi Kivity <avi@qumranet.com>

Fix some issues in pagemap_read noted by Alexey:

- initialize pagemap_walk.mm to "mm" , so the code starts working as
  advertised

- initialize ->private to "&pm" so it wouldn't immediately oops in
  pagemap_pte_hole()

- unstatic struct pagemap_walk, so two threads won't fsckup each other
  (including those started by root, including flipping ->mm when you don't
  have permissions)

- pagemap_read() contains two calls to ptrace_may_attach(), second one
  looks unneeded.

- avoid possible kmalloc(0) and integer wraparound.

Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
[ Personally, I'd just remove the functionality entirely  - Linus ]
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

These two macros are useful beyond lock debugging. Moved definitions from
include/linux/debug_locks.h to include/linux/kernel.h, so code that needs
them does not have to include the former, which would have been a less
intuitive choice of a header.
Signed-off-by: NEduard - Gabriel Munteanu <eduard.munteanu@linux360.ro>
Acked-by: NPekka Enberg <penberg@cs.helsinki.fi>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge branch 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'core-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  softlockup: print a module list on being stuck

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86 ACPI: fix resume from suspend to RAM on uniprocessor x86-64
  x86 ACPI: normalize segment descriptor register on resume

Don't use a static entry, so as to prevent races during concurrent use
of this function.
Reported-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6:
  ide: ide_unregister() locking bugfix
  ide: ide_unregister() warm-plug bugfix
  ide: fix hwif->gendev refcounting

Commit ea0c62f7 tried to clear all
bits in irq_stat but it didn't actually achieve that as irq_stat was
anded with port_map right after read.  This patch makes ahci driver
always use the unmasked value to clear irq_status.

While at it, add explanation on the peculiarities of ahci IRQ
clearing.

This was spotted by Linus Torvalds.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Holding ide_lock for ide_release_dma_engine() call is unnecessary
and triggers WARN_ON(irqs_disabled()) in dma_free_coherent().
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Fix ide_unregister() to work for ports with no devices attached to them.
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

class->dev_release is called by device_release() iff dev->release
is not present so ide_port_class_release() is never called and the
last hwif->gendev reference is not dropped.

Fix it by removing ide_port_class_release() and get_device() call
from ide_register_port() (device_create_drvdata() takes a hwif->gendev
reference anyway).

This patch fixes hang on wait_for_completion(&hwif->gendev_rel_comp)
in ide_unregister() reported by Pavel Machek.

Cc: Pavel Machek <pavel@suse.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: NBartlomiej Zolnierkiewicz <bzolnier@gmail.com>

Most places in the kernel that go BUG: print a module list
(which is very useful for doing statistics and finding patterns),
however the softlockup detector does not do this yet.

This patch adds the one line change to fix this gap.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Since the trampoline code is now used for ACPI resume from suspend to RAM,
the trampoline page tables have to be fixed up during boot not only on SMP
systems, but also on UP systems that use the trampoline.

Reference: http://bugzilla.kernel.org/show_bug.cgi?id=10923Reported-by: NDionisus Torimens <djtm@gmx.net>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: pm list <linux-pm@lists.linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Some Dell laptops enter resume with apparent garbage in the segment
descriptor registers (almost certainly the result of a botched
transition from protected to real mode.)  The only way to clean that
up is to enter protected mode ourselves and clean out the descriptor
registers.

This fixes resume on Dell XPS M1210 and Dell D620.

Reference: http://bugzilla.kernel.org/show_bug.cgi?id=10927Signed-off-by: NH. Peter Anvin <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: pm list <linux-pm@lists.linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Tested-by: NKirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Flags considered internal to the mempolicy kernel code are stored as part
of the "flags" member of struct mempolicy.

Before exposing a policy type to userspace via get_mempolicy(), these
internal flags must be masked.  Flags exposed to userspace, however,
should still be returned to the user.
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  xen: fix address truncation in pte mfn<->pfn conversion
  arch/x86/mm/init_64.c: early_memtest(): fix types
  x86: fix Intel Mac booting with EFI

Even the newer ENE controllers have bugs in their DMA engine that make
it too dangerous to use. Disable it until someone has figured out under
which conditions it corrupts data.

This has caused problems at least once, and can be found as bug report
10925 in the kernel bugzilla.
Signed-off-by: NPierre Ossman <drzeus@drzeus.cx>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Document the kernel boot parameter: relax_domain_level=.
Signed-off-by: NPaul Jackson <pj@sgi.com>
Cc: Michael Kerrisk <mtk.manpages@googlemail.com>
Reviewed-by: NLi Zefan <lizf@cn.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

 # cat /devcg/devices.list
 a *:* rwm
 # echo a > devices.allow
 # cat /devcg/devices.list
 a *:* rwm
 a 0:0 rwm

This is odd and maybe confusing.  With this patch, writing 'a' to
devices.allow will add 'a *:* rwm' to the whitelist.

Also a few fixes and updates to the document.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Cc: Serge E. Hallyn <serue@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
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>

Acked-By: NDebora Velarde <debora@linux.vnet.ibm.com>
Cc: <zohar@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

There is a bug in the output of /sys/devices/system/node/node[n]/meminfo
where the Active and Inactive values are in pages instead of Kbytes.

Looks like this occurred back in 2.6.20 when the code was changed
over to use node_page_state().

Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In linux-next there is a commit ("x86: Add performance variants of cpumask
operators") which, as part of the 4096 cpu support work adds some new APIs
for dealing with cpu masks.  Add trivial versions of these now so that
subsystems can update in a timely manner and avoid conflicts in linux-next
and the next merge window.

Cc: Mike Travis <travis@sgi.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The CaFe chip has a hardware bug that ends up with us getting a timeout
value that's too small, causing the following sorts of problems:

[   60.525138] mmcblk0: error -110 transferring data
[   60.531477] end_request: I/O error, dev mmcblk0, sector 1484353
[   60.533371] Buffer I/O error on device mmcblk0p2, logical block 181632
[   60.533371] lost page write due to I/O error on mmcblk0p2

Presumably this is an off-by-one error in the hardware.  Incrementing
the timeout count value that we stuff into the TIMEOUT_CONTROL register
gets us a value that works.  This bug was originally discovered by
Pierre Ossman, I believe.

[thanks to Robert Millan for proving that this was still a problem]
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This has been sitting around unloved for way too long..

The Marvell CaFe chip's SD implementation chokes during card insertion
if one attempts to set the voltage and power up in the same
SDHCI_POWER_CONTROL register write.  This adds a quirk that does
that particular dance in two steps.

It also adds an entry to pci_ids.h for the CaFe chip's SD device.
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Cc: Pierre Ossman <drzeus-list@drzeus.cx>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch changes the way we determine the maximum number of outstanding
commands for each controller.

Most Smart Array controllers can support up to 1024 commands, the notable
exceptions are the E200 and E200i.

The next generation of controllers which were just added support a mode of
operation called Zero Memory Raid (ZMR).  In this mode they only support
64 outstanding commands.  In Full Function Raid (FFR) mode they support
1024.

We have been setting the queue depth by arbitrarily assigning some value
for each controller.  We needed a better way to set the queue depth to
avoid lots of annoying "fifo full" messages.  So we made the driver a
little smarter.  We now read the config table and subtract 4 from the
returned value.  The -4 is to allow some room for ioctl calls which are
not tracked the same way as io commands are tracked.

Please consider this for inclusion.
Signed-off-by: NMike Miller <mike.miller@hp.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The old one bounces.
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Cc: Andreas Dilger <adilger@sun.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Provide a little documentation for the two new fields, Cpus_allowed_list
and Mems_allowed_list, that were added to each /proc/<pid>/status file a
while back.
Signed-off-by: NPaul Jackson <pj@sgi.com>
Acked-by: NMichael Kerrisk <mtk.manpages@gmail.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The build of the Alpha Linux kernel currently fails[1] with inconsistent
kallsyms data.  As I never saw that before, I thought about hardware
problems.  But in fact it is a bug in the Linux kernel.

The end of the rodata section is marked with the "__end_rodata" symbol.
This symbol have different aligning constraints than the inittext parts
and therefor the start marked "_sinittext".  Because of that the
__end_rodata symbol shifts between < _sinittext and == _sinittext.  The
later variant is seen as a code symbol and recorded in the kallsyms data.

On fix would be to move the exception table a little bit and get some
space between that two areas.

[1]: http://buildd.debian.org/fetch.cgi?pkg=linux-2.6&arch=alpha&ver=2.6.25-5&stamp=1213919009&file=log&as=raw

Cc: maximilian attems <max@stro.at>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The filesystem capability support meaning for CAP_SETPCAP is less powerful
than the non-filesystem capability support.  As such, when filesystem
capabilities are configured, we should not permit CAP_SETPCAP to 'enhance'
the current process through strace manipulation of a child process.
Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This commit includes a bugfix for the fragile setuid fixup code in the
case that filesystem capabilities are supported (in access()).  The effect
of this fix is gated on filesystem capability support because changing
securebits is only supported when filesystem capabilities support is
configured.)

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NAndrew G. Morgan <morgan@kernel.org>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Maintain the kernel's Documentation/ tree.

This includes tree layout and contents, although not much in terms of new
content production.  That will usually have to be done by someone familiar
with the software, at least in some rough form.

Includes review and editorial assistance for people contributing changes
to /Documentation.

Also includes prodding people for content if something is in need of
documentation.
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Acked-by: NMichael Kerrisk <mtk.manpages@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This got broken by the recent "fix rmmod $spi_driver while spidev-user is
active".  I tested the rmmod & write path but didn't check the read path.
I am sorry.  The read logic changed and spidev_sync_read() +
spidev_sync_write() do not return zero on success anymore but the number
of bytes that has been transfered over the bus.  This patch changes the
logic and copy_to_user() gets called again.

The write path returns the number of bytes which are written to the
underlying device what may be less than the requested size.  This patch
makes the same change to the read path or else we request a read of 20
bytes, get 10, don't call copy to user and report to the user that we read
10 bytes.

[akpm@linux-foundation.org: remove test of known-to-be-zero local]
Signed-off-by: NSebastian Siewior <bigeasy@linutronix.de>
Acked-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Document that a pid of zero(0) can be used to refer to the current task
when attaching a task to a cgroup, as in the following usage:

	# echo 0 > /dev/cgroup/tasks

This is consistent with existing cpuset behavior.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPaul Jackson <pj@sgi.com>
Acked-by: NDhaval Giani <dhaval@linux.vnet.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Andrea Righi <righi.andrea@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>