Impact: fix boot crash with numcpus=0 on certain systems

Fix early exception in __get_smp_config with nosmp.

Bail out early when there is no MP table.
Reported-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Tested-by: NWu Fengguang <fengguang.wu@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge branch 'oprofile-for-tip' of git://git.kernel.org/pub/scm/linux/kernel/git/rric/oprofile into x86/urgent

Alan Jenkins wrote:
> This is on an EeePC 701, /proc/cpuinfo as attached.
>
> Is this expected?  Will the next release work?
>
> Thanks, Alan
>
> # opcontrol --setup --no-vmlinux
> cpu_type 'unset' is not valid
> you should upgrade oprofile or force the use of timer mode
>
> # opcontrol -v
> opcontrol: oprofile 0.9.4 compiled on Nov 29 2008 22:44:10
>
> # cat /dev/oprofile/cpu_type
> i386/p6
> # uname -r
> 2.6.28-rc6eeepc

Hi Alan,

Looking at the kernel driver code for oprofile it can return the "i386/p6" for
the cpu_type. However, looking at the user-space oprofile code there isn't the
matching entry in libop/op_cpu_type.c or the events/unit_mask files in
events/i386 directory.

The Intel AP-485 says this is a "Intel Pentium M processor model D". Seems like
the oprofile kernel driver should be identifying the processor as "i386/p6_mobile"

The driver identification code doesn't look quite right in nmi_init.c

http://git.kernel.org/?p=linux/kernel/git/sfr/linux-next.git;a=blob;f=arch/x86/oprofile/nmi_int.c;h=022cd41ea9b4106e5884277096e80e9088a7c7a9;hb=HEAD

has:

409         case 10 ... 13:
410                 *cpu_type = "i386/p6";
411                 break;

Referring to the Intel AP-485:
case 10 and 11 should produce "i386/piii"
case 13 should produce "i386/p6_mobile"

I didn't see anything for case 12.

Something like the attached patch. I don't have a celeron machine to verify that
changes in this area of the kernel fix thing.

-Will
Signed-off-by: NWilliam Cohen <wcohen@redhat.com>
Tested-by: NAlan Jenkins <alan-jenkins@tuffmail.co.uk>
Acked-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

If oprofile statically compiled in kernel, a cpu unplug triggers
a panic in ppro_stop(), because a NULL pointer is dereferenced.
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NRobert Richter <robert.richter@amd.com>

Merge branch 'iommu-fixes-2.6.28' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu into x86/urgent

The access to the iommu->need_sync member needs to be protected by the
iommu->lock. Otherwise this is a possible race condition. Fix it with
this patch.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

In some rare cases a request can arrive an IOMMU with its originial
requestor id even it is aliased. Handle this by setting the device table
entry to the same protection domain for the original and the aliased
requestor id.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Remove 16 bytes of padding from struct amd_iommu on 64bit builds
reducing its size to 120 bytes, allowing it to span one fewer
cachelines.
Signed-off-by: NRichard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>

Impact: remove stale IOTLB entries

In the non-default nofullflush case the GART is only flushed when
next_bit wraps around. But it can happen that an unmap operation unmaps
memory which is behind the current next_bit location. If these addresses
are reused it may result in stale GART IO/TLB entries. Fix this by
setting the GART next_bit always behind an unmapped location.
Signed-off-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (25 commits)
  em28xx: remove backward compat macro added on a previous fix
  V4L/DVB (9748): em28xx: fix compile warning
  V4L/DVB (9743): em28xx: fix oops audio
  V4L/DVB (9742): em28xx-alsa: implement another locking schema
  V4L/DVB (9732): sms1xxx: use new firmware for Hauppauge WinTV MiniStick
  V4L/DVB (9691): gspca: Move the video device to a separate area.
  V4L/DVB (9690): gspca: Lock the subdrivers via module_get/put.
  V4L/DVB (9689): gspca: Memory leak when disconnect while streaming.
  V4L/DVB (9668): em28xx: fix a race condition with hald
  V4L/DVB (9664): af9015: don't reconnect device in USB-bus
  V4L/DVB (9647): em28xx: void having two concurrent control URB's
  V4L/DVB (9646): em28xx: avoid allocating/dealocating memory on every control urb
  V4L/DVB (9645): em28xx: Avoid memory leaks if registration fails
  V4L/DVB (9639): Make dib0700 remote control support work with firmware v1.20
  V4L/DVB (9635): v4l: s2255drv fix firmware test on big-endian
  V4L/DVB (9634): Make sure the i2c gate is open before powering down tuner
  V4L/DVB (9632): make em28xx aux audio input work
  V4L/DVB (9631): Make s2api work for ATSC support
  V4L/DVB (9627): em28xx: Avoid i2c register error for boards without eeprom
  V4L/DVB (9608): Fix section mismatch warning for dm1105 during make
  ...

drivers/gpu/drm/i915/i915_irq.c: In function 'i915_disable_pipestat':
drivers/gpu/drm/i915/i915_irq.c:101: warning: control may reach end of non-void function 'i915_pipestat' being inlined

Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix module removal bugs of i82875p_edac.  Also i82975x_edac code seems to
have the same module removal bugs as in i82875p_edac.

The problems were:

1. In module removal i82875p_remove_one() is never called.

   Variable i82875p_registered is newer changed from 1, which
   guarantees i82875p_remove_one() is not called (and even if it were
   called, it would be called in wrong order).

   As a result, the edac_mc workque is not stopped and keeps probing.
   If kernel debugging options are not enabled, user may not notice
   anything going wrong.

   if debugging options are enabled and I do "rmmod i82875p_edac", I
   get:

      edac debug: edac_pci_workq_function() checking
      BUG: unable to handle kernel paging request at f882d16f
      ...
      call trace:
       [<f8834df3>] ? edac_mc_workq_function+0x55/0x7e [edac_core]
       [<c0233974>] ? run_workqueue+0xd7/0x1a5
       [<c023392f>] ? run_workqueue+0x92/0x1a5
       [<f8834d9e>] ? edac_mc_workq_function+0x0/0x7e [edac_core]
       [<c0233af9>] ? worker_thread+0xb7/0xc3
       [<c0236a7b>] ? autoremove_wake_function+0x0/0x33
       [<c0233a42>] ? worker_thread+0x0/0xc3
       [<c0236809>] ? kthread+0x3b/0x61
       [<c02367ce>] ? kthread+0x0/0x61
       [<c0204587>] ? kernel_thread_helper+0x7/0x10

   Fix for this is to get rid of needles variable i82875p_registered
   altogether and run i82875p_remove_one() *before*
   pci_unregister_driver().

2. edac_mc_del_mc() uses mci after freeing mci

   edac_mc_del_mc() calls calls edac_remove_sysfs_mci_device().  The
   kobject refcount of mci drops to 0 and mci is freed.  After this
   mci is accessed via debug print and i82875p_remove_one() still
   uses mci->pvt and tries to free mci again with edac_mc_free().

   The fix for this is add kobject_get(&mci->edac_mci_kobj) after
   edac_mc_alloc(). Then the mci is still available after returning
   from edac_mc_del_mc() with refcount 1, and mci->pvt is still
   available. When i82875p_remove_one() finally calls edac_mc_free(),
   this will cause kobject_put() and mci is released properly.
Signed-off-by: NJarkko Lavinen <jlavi@iki.fi>
Cc: Doug Thompson <norsk5@yahoo.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>

When I do "modprobe i82875p_edac" on my Asus P4C800 MB on kernels 2.6.26
or later, the module load fails due to BAR 0 collision.  On 2.6.25 the
module loads just fine.

The overflow device on the MB seems to be hidden and its resources are not
allocated at normal PCI bus init.  Log shows the missing resource problem:

  EDAC DEBUG: i82875p_probe1()
  PCI: 0000:00:06.0 reg 10 32bit mmio: [fecf0000, fecf0fff]
  pci 0000:00:06.0: device not available because of BAR 0
[0xfecf0000-0xfecf0fff] collisions
  EDAC i82875p: i82875p_setup_overfl_dev(): Failed to enable overflow
device

The patch below fixes this by calling pci_bus_assign_resources() after
the overflow device is revealed and added to the bus. With this patch
I am again able to load and use the module.
Signed-off-by: NJarkko Lavinen <jlavi@iki.fi>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
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>

The commit aef7db4b fixed the problem with
recursive locking in fb blanking code if blank is caused by user setting
the /sys/class/graphics/fb*/blank.  However this broke the fbcon timeout
blanking.

If you use a driver that defines ->fb_blank operation and at the same time
that driver relies on other driver (e.g.  backlight or lcd class) to blank
the screen, when the fbcon times out and tries to blank the fb, it will
call only fb driver blanker and won't notify the other driver.  Thus FB
output is disabled, but the screen isn't blanked.

Restore fbcon blanking and at the same time apply the proper fix for the
above problem: if fbcon_blank is called with FBINFO_FLAG_USEREVENT, we are
already called through notification from fb_blank, thus we don't have to
blank the fb again.
Signed-off-by: NDmitry Baryshkov <dbaryshkov@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

kernel-doc handles macros now (it has for quite some time), so change the
ntfs_debug() macro's kernel-doc to be just before the macro instead of
before a phony function prototype.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Cc: Anton Altaparmakov <aia21@cantab.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The method for listing varargs in kernel-doc notation is:
 * @...: these arguments are printed by the @fmt argument

but scripts/kernel-doc is confused:  it always lists varargs as:
	...	variable arguments
and ignores the @...: line's description, but then prints that
line after the list of function parameters as though it's
not part of the function parameters.

This patch makes kernel-doc print the supplied @...  description if it is
present; otherwise a boilerplate "variable arguments" is printed.
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>

2nd part of the fixes needed for
http://bugzilla.kernel.org/show_bug.cgi?id=11796.

When the idr tree is either grown or shrunk, then the update to the number
of layers and the top pointer were not atomic.  This race caused crashes.

The attached patch fixes that by replicating the layers counter in each
layer, thus idr_find doesn't need idp->layers anymore.
Signed-off-by: NManfred Spraul <manfred@colorfullife.com>
Cc: Clement Calmels <cboulte@gmail.com>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: Pierre Peiffer <peifferp@gmail.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

- pci_map_sg/dma_map_sg are used with a scatter gather list that doesn't
  come from the block layer (e.g.  some network drivers do).

- how IOMMUs merge adjacent elements of the scatter/gather list is
  independent of how the block layer determines sees elements.
Signed-off-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix the error handling in sys_mmap2().  Currently, if the pgoff check
fails, fput() might have to be called (which it isn't), so do the pgoff
check first, before fget() is called.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Reported-by: NJulia Lawall <julia@diku.dk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The description for 'D' was missing in the comment...  (causing me a
minute of WTF followed by looking at more of the code)
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The engine on some radeon variants locks up if color expansion is called
for non aligned source data.  This patch enables a feature of the core
fbdev to request aligned input pixmaps and uses the HW clipping engine to
clip the output to the requested size

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=11875Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: NJames Cloos <cloos@jhcloos.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The spi master driver must have num_chipselect set to allow the bus to
initialise.  Pass this through the platform data.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-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>

The spidev_to_sg() call in spi_s3c24xx_gpio.c was using the wrong method
to convert the spi device into the private data for the driver.  Fix this
by using spi_master_get_devdata.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-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>

Fix unsafe order in dma mapping operation: always flush data from the
cache *BEFORE* invalidating it, to allow full duplex transfers where the
same buffer may be used for both writes and reads.  Tested with mmc-spi.
Signed-off-by: NJan Nikitenko <jan.nikitenko@gmail.com>
Signed-off-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>

Corrects spi_imx driver oops during initialization/probing: can't use
drv_data before it's allocated.
Signed-off-by: NJulien Boibessot <julien.boibessot@armadeus.com>
Acked-by: NSascha Hauer <s.hauer@pengutronix.de>
Signed-off-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>

It has been thought that the per-user file descriptors limit would also
limit the resources that a normal user can request via the epoll
interface.  Vegard Nossum reported a very simple program (a modified
version attached) that can make a normal user to request a pretty large
amount of kernel memory, well within the its maximum number of fds.  To
solve such problem, default limits are now imposed, and /proc based
configuration has been introduced.  A new directory has been created,
named /proc/sys/fs/epoll/ and inside there, there are two configuration
points:

  max_user_instances = Maximum number of devices - per user

  max_user_watches   = Maximum number of "watched" fds - per user

The current default for "max_user_watches" limits the memory used by epoll
to store "watches", to 1/32 of the amount of the low RAM.  As example, a
256MB 32bit machine, will have "max_user_watches" set to roughly 90000.
That should be enough to not break existing heavy epoll users.  The
default value for "max_user_instances" is set to 128, that should be
enough too.

This also changes the userspace, because a new error code can now come out
from EPOLL_CTL_ADD (-ENOSPC).  The EMFILE from epoll_create() was already
listed, so that should be ok.

[akpm@linux-foundation.org: use get_current_user()]
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: <stable@kernel.org>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Reported-by: NVegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

According to the manual the "tdfOnExit" flag must be set on the last byte
we want to send.  The PSC controller holds SS low until the flag is set.

However, the flag was set always on the last byte of the FIFO,
independently if it is the last byte of the transfer.  This generates
spurious toggling of the SS signals that breaks the protocol of some
peripherals.  Fix.
Signed-off-by: NStefano Babic <sbabic@denx.de>
Acked-by: NGrant Likely <grant.likely@secretlab.ca>
Signed-off-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>

I saw a kernel oops in spidev_remove() when a spidev device was registered
and I unloaded the SPI master driver:

Unable to handle kernel paging request for data at address 0x00000004
Faulting instruction address: 0xc01c0c50
Oops: Kernel access of bad area, sig: 11 [#1]
CDSPR
Modules linked in: spi_ppc4xx(-)
NIP: c01c0c50 LR: c01bf9e4 CTR: c01c0c34
REGS: cec89c30 TRAP: 0300   Not tainted  (2.6.27.3izt)
MSR: 00021000 <ME>  CR: 24000228  XER: 20000007
DEAR: 00000004, ESR: 00800000
TASK = cf889040[2070] 'rmmod' THREAD: cec88000
GPR00: 00000000 cec89ce0 cf889040 cec8e000 00000004 cec8e000 ffffffff 00000000
GPR08: 0000001c c0336380 00000000 c01c0c34 00000001 1001a338 100e0000 100df49c
GPR16: 100b54c0 100df49c 100ddd20 100f05a8 100b5340 100efd68 00000000 00000000
GPR24: 100ec008 100f0428 c0327788 c0327794 cec8e0ac cec8e000 c0336380 00000000
NIP [c01c0c50] spidev_remove+0x1c/0xe4
LR [c01bf9e4] spi_drv_remove+0x2c/0x3c
Call Trace:
[cec89d00] [c01bf9e4] spi_drv_remove+0x2c/0x3c
[cec89d10] [c01859a0] __device_release_driver+0x78/0xb4
[cec89d20] [c0185ab0] device_release_driver+0x28/0x44
[cec89d40] [c0184be8] bus_remove_device+0xac/0xd8
[cec89d60] [c0183094] device_del+0x100/0x194
[cec89d80] [c0183140] device_unregister+0x18/0x30
[cec89da0] [c01bf30c] __unregister+0x20/0x34
[cec89db0] [c0182778] device_for_each_child+0x38/0x74
[cec89de0] [c01bf2d0] spi_unregister_master+0x28/0x44
[cec89e00] [c01bfeac] spi_bitbang_stop+0x1c/0x58
[cec89e20] [d908a5e0] spi_ppc4xx_of_remove+0x24/0x7c [spi_ppc4xx]
[...]

IMHO a call to spi_set_drvdata() is missing in spidev_probe(). The patch
below helped.
Signed-off-by: NWolfgang Ocker <weo@reccoware.de>
Signed-off-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>

Use __initdata for data, not __init.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-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>

make use of the new dmi device loading support to automatically load the
applesmc driver based on the dmi_match table.
Signed-off-by: NHenrik Rydberg <rydberg@euromail.se>
Cc: Nicolas Boichat <nicolas@boichat.ch>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The netmos_9xx5_combo type assumes that PCI SSID provides always the
correct value for the number of parallel and serial ports, but there are
indeed broken devices with wrong numbers, which may result in Oops.

This patch simply adds the check of the array range.

Reference: Novell bnc#447067
	https://bugzilla.novell.com/show_bug.cgi?id=447067Signed-off-by: NTakashi Iwai <tiwai@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fixes for memcg/memory hotplug.

While memory hotplug allocate/free memmap, page_cgroup doesn't free
page_cgroup at OFFLINE when page_cgroup is allocated via bootomem.
(Because freeing bootmem requires special care.)

Then, if page_cgroup is allocated by bootmem and memmap is freed/allocated
by memory hotplug, page_cgroup->page == page is no longer true.

But current MEM_ONLINE handler doesn't check it and update
page_cgroup->page if it's not necessary to allocate page_cgroup.  (This
was not found because memmap is not freed if SPARSEMEM_VMEMMAP is y.)

And I noticed that MEM_ONLINE can be called against "part of section".
So, freeing page_cgroup at CANCEL_ONLINE will cause trouble.  (freeing
used page_cgroup) Don't rollback at CANCEL.

One more, current memory hotplug notifier is stopped by slub because it
sets NOTIFY_STOP_MASK to return vaule.  So, page_cgroup's callback never
be called.  (low priority than slub now.)

I think this slub's behavior is not intentional(BUG). and fixes it.

Another way to be considered about page_cgroup allocation:
  - free page_cgroup at OFFLINE even if it's from bootmem
    and remove specieal handler. But it requires more changes.

Addresses http://bugzilla.kernel.org/show_bug.cgi?id=12041Signed-off-by: NKAMEZAWA Hiruyoki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Li Zefan <lizf@cn.fujitsu.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Tested-by: NBadari Pulavarty <pbadari@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Jim Radford has reported that the vmap subsystem rewrite was sometimes
causing his VIVT ARM system to behave strangely (seemed like going into
infinite loops trying to fault in pages to userspace).

We determined that the problem was most likely due to a cache aliasing
issue.  flush_cache_vunmap was only being called at the moment the page
tables were to be taken down, however with lazy unmapping, this can happen
after the page has subsequently been freed and allocated for something
else.  The dangling alias may still have dirty data attached to it.

The fix for this problem is to do the cache flushing when the caller has
called vunmap -- it would be a bug for them to write anything else to the
mapping at that point.

That appeared to solve Jim's problems.
Reported-by: NJim Radford <radford@blackbean.org>
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2:
  ocfs2: fix regression in ocfs2_read_blocks_sync()
  ocfs2: fix return value set in init_dlmfs_fs()
  ocfs2: Small documentation update
  ocfs2: fix wake_up in unlock_ast
  ocfs2: initialize stack_user lvbptr
  ocfs2: comments typo fix

We're panicing in ocfs2_read_blocks_sync() if a jbd-managed buffer is seen.
At first glance, this seems ok but in reality it can happen. My test case
was to just run 'exorcist'. A struct inode is being pushed out of memory but
is then re-read at a later time, before the buffer has been checkpointed by
jbd. This causes a BUG to be hit in ocfs2_read_blocks_sync().
Reviewed-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

In init_dlmfs_fs(), if calling kmem_cache_create() failed, the code will use return value from
calling bdi_init(). The correct behavior should be set status as -ENOMEM before going to "bail:".
Signed-off-by: NColy Li <coyli@suse.de>
Acked-by: NSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

Remove some features from the "not-supported" list that are actually
supported now.
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

In ocfs2_unlock_ast(), call wake_up() on lockres before releasing
the spin lock on it.  As soon as the spin lock is released, the
lockres can be freed.
Signed-off-by: NDavid Teigland <teigland@redhat.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>

The locking_state dump, ocfs2_dlm_seq_show, reads the lvb on locks where it
has not yet been initialized by a lock call.
Signed-off-by: NDavid Teigland <teigland@redhat.com>
Acked-by: NJoel Becker <joel.becker@oracle.com>
Signed-off-by: NMark Fasheh <mfasheh@suse.com>