1) drvdata is for a driver to store a pointer to driver specific data
2) If no driver is bound, there is no driver specific data associated with
   the device
3) Thus logically drvdata should be NULL if no driver is bound.

But many drivers don't clear drvdata on device_release, or set drvdata
early on in probe and leave it set on probe error. Both of which results
in a dangling pointer in drvdata.

This patch enforce for drvdata to be NULL after device_release or on probe
failure.
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The 'mutex' in struct w1_master is use for two very different
purposes.

Firstly it protects various data structures such as the list of all
slaves.

Secondly it protects the w1 buss against concurrent accesses.

This can lead to deadlocks when the ->probe code called while adding a
slave needs to talk on the bus, as is the case for power_supply
devices.
ds2780 and ds2781 drivers contain a work around to track which
process hold the lock simply to avoid this deadlock.  bq27000 doesn't
have that work around and so deadlocks.

There are other possible deadlocks involving sysfs.
When removing a device the sysfs s_active lock is held, so the lock
that protects the slave list must take precedence over s_active.
However when access power_supply attributes via sysfs, the s_active
lock must take precedence over the lock that protects accesses to
the bus.

So to avoid deadlocks between w1 slaves and sysfs, these must be
two separate locks.  Making them separate means that the work around
in ds2780 and ds2781 can be removed.

So this patch:
 - adds a new mutex: "bus_mutex" which serialises access to the bus.
 - takes in mutex in w1_search and ds1wm_search while they access
   the bus for searching.  The mutex is dropped before calling the
   callback which adds the slave.
 - changes all slaves to use bus_mutex instead of mutex to
   protect access to the bus
 - removes w1_ds2790_io_nolock and w1_ds2781_io_nolock, and the
   related code from drivers/power/ds278[01]_battery.c which
   calls them.
Signed-off-by: NNeilBrown <neilb@suse.de>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There is no gain in having a loop - there is no risk of missing the
interrupt with wait_event_timeout.
Signed-off-by: NNeilBrown <neilb@suse.de>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

- some debug messages missed spaces
- sometimes no error was returned when it should have been
- sometimes a message is printed when there is no error, rather
  than when there is one.
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This reverts commit 59d4467b.

Turns out it was the wrong version, will apply the correct version after
this.
Reported-by: NNeilBrown <neilb@suse.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There were some return statements around in the w1_uevent, used goto
to cleanup those return statements with the help of err variable,
and also removed a semi colon at the end of the w1_uevent's closing
brace.
Signed-off-by: NDevendra Naga <devendra.aaru@gmail.com>
Acked-by: NEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

w1 devices need a mutex to serial IO.  Most use master->mutex.
However that is used for other purposes and they can conflict.

In particular master->mutex is held while w1_attach_slave_device is
called.

For bq27000, this registers a 'powersupply' device which tries to read the
current status.  The attempt to read will cause a deadlock on
master->mutex.

So create a new per-slave mutex and use that for serializing IO for
bq27000.
Signed-off-by: NNeilBrown <neilb@suse.de>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If !dev->class, device_move() does not respect the dpm_order.
Fix it to do so.
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NRabin Vincent <rabin.vincent@stericsson.com>
Reviewed-by: NSrinidhi Kasagar <srinidhi.kasagar@stericsson.com>
[Fixed a small dangling label compile warning]
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

If the privileges given to root threads (3% of allowable memory) or a
negative value of /proc/pid/oom_score_adj happen to exceed the amount of
rss of a thread, its badness score overflows as a result of commit
a7f638f9 ("mm, oom: normalize oom scores to oom_score_adj scale only
for userspace").

Fix this by making the type signed and return 1, meaning the thread is
still eligible for kill, if the value is negative.
Reported-by: NDave Jones <davej@redhat.com>
Acked-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NDavid Rientjes <rientjes@google.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull scheduler fixes from Ingo Molnar.

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix the relax_domain_level boot parameter
  sched: Validate assumptions in sched_init_numa()
  sched: Always initialize cpu-power
  sched: Fix domain iteration
  sched/rt: Fix lockdep annotation within find_lock_lowest_rq()
  sched/numa: Load balance between remote nodes
  sched/x86: Calculate booted cores after construction of sibling_mask

Fix lots of new kernel-doc warnings in kernel/sched/fair.c:

  Warning(kernel/sched/fair.c:3625): No description found for parameter 'env'
  Warning(kernel/sched/fair.c:3625): Excess function parameter 'sd' description in 'update_sg_lb_stats'
  Warning(kernel/sched/fair.c:3735): No description found for parameter 'env'
  Warning(kernel/sched/fair.c:3735): Excess function parameter 'sd' description in 'update_sd_pick_busiest'
  Warning(kernel/sched/fair.c:3735): Excess function parameter 'this_cpu' description in 'update_sd_pick_busiest'
  .. more warnings
Signed-off-by: NRandy Dunlap <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 9e612a00.

It incorrectly finds VGA connectors where none are attached, apparently
not noticing that nothing replied to the EDID queries, and happily using
the default EDID modes that have nothing to do with actual hardware.

That in turn then causes X to fall down to the lowest common
denominator, which is usually the default 1024x768 mode that is in the
default EDID and pretty much anything supports).

I'd suggest that if not relying on the HDP pin, the code should at least
check whether it gets valid EDID data back, rather than just assume
there's something on the VGA connector.

Cc: Dave Airlie <airlied@linux.ie>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull ext4 bug fixes from Theodore Ts'o:
 "This update contains two bug fixes, both destined for the stable tree.
  Perhaps the most important is one which fixes ext4 when used with file
  systems originally formatted for use with ext3, but then later
  converted to take advantage of ext4."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: don't set i_flags in EXT4_IOC_SETFLAGS
  ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg

Pull powerpc fixes from Paul Mackerras:
 "Two small fixes for powerpc:
   - a fix for a regression since 3.2 that causes 4-second (or longer)
     pauses
   - a fix for a potential oops when loading kernel modules on 32-bit
     embedded systems."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Fix kernel panic during kernel module load
  powerpc/time: Sanity check of decrementer expiration is necessary

Pull UBI/UBIFS fixes from Artem Bityutskiy:
 "Fix UBI and UBIFS - they refuse to work without debugfs.  This was
  broken by the 3.5-rc1 UBI/UBIFS changes when we removed the debugging
  Kconfig switches.

  Also, correct locking in 'ubi_wl_flush()' - it was extended to support
  flushing a specific LEB in 3.5-rc1, and the locking was sub-optimal."

* tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs:
  UBI: correct ubi_wl_flush locking
  UBIFS: fix debugfs-less systems support
  UBI: fix debugfs-less systems support

This reverts commit 7732a557 (and commit
3f50fff4, which was a follow-up
cleanup).

We're chasing an elusive bug that Dave Jones can apparently reproduce
using his system call fuzzer tool, and that looks like some kind of
locking ordering problem on the directory i_mutex chain.  Our i_mutex
locking is rather complex, and depends on the topological ordering of
the directories, which is why we have been very wary of splicing
directory entries around.

Of course, we really don't want to ever see aliased unconnected
directories anyway, so none of this should ever happen, but this revert
aims to basically get us back to a known older state.

Bruce points to some of the previous discussion at

       http://marc.info/?i=<20110310105821.GE22723@ZenIV.linux.org.uk>

and in particular a long post from Neil:

       http://marc.info/?i=<20110311150749.2fa2be66@notabene.brown>

It should be noted that it's possible that Dave's problems come from
other changes altohgether, including possibly just the fact that Dave
constantly is teachning his fuzzer new tricks.  So what appears to be a
new bug could in fact be an old one that just gets newly triggered, but
reverting these patches as "still under heavy discussion" is the right
thing regardless.
Requested-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NJ. Bruce Fields <bfields@fieldses.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull x86 fixes from Ingo Molnar.

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/nmi: Fix section mismatch warnings on 32-bit
  x86/uv: Fix UV2 BAU legacy mode
  x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space
  x86, efi stub: Add .reloc section back into image
  x86/ioapic: Fix NULL pointer dereference on CPU hotplug after disabling irqs
  x86/reboot: Fix a warning message triggered by stop_other_cpus()
  x86/intel/moorestown: Change intel_scu_devices_create() to __devinit
  x86/numa: Set numa_nodes_parsed at acpi_numa_memory_affinity_init()
  x86/gart: Fix kmemleak warning
  x86: mce: Add the dropped timer interval init back
  x86/mce: Fix the MCE poll timer logic

Pull perf fixes from Ingo Molnar:
 "A bit larger than what I'd wish for - half of it is due to hw driver
  updates to Intel Ivy-Bridge which info got recently released,
  cycles:pp should work there now too, amongst other things.  (but we
  are generally making exceptions for hardware enablement of this type.)

  There are also callchain fixes in it - responding to mostly
  theoretical (but valid) concerns.  The tooling side sports perf.data
  endianness/portability fixes which did not make it for the merge
  window - and various other fixes as well."

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  perf/x86: Check user address explicitly in copy_from_user_nmi()
  perf/x86: Check if user fp is valid
  perf: Limit callchains to 127
  perf/x86: Allow multiple stacks
  perf/x86: Update SNB PEBS constraints
  perf/x86: Enable/Add IvyBridge hardware support
  perf/x86: Implement cycles:p for SNB/IVB
  perf/x86: Fix Intel shared extra MSR allocation
  x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix
  perf: Remove duplicate invocation on perf_event_for_each
  perf uprobes: Remove unnecessary check before strlist__delete
  perf symbols: Check for valid dso before creating map
  perf evsel: Fix 32 bit values endianity swap for sample_id_all header
  perf session: Handle endianity swap on sample_id_all header data
  perf symbols: Handle different endians properly during symbol load
  perf evlist: Pass third argument to ioctl explicitly
  perf tools: Update ioctl documentation for PERF_IOC_FLAG_GROUP
  perf tools: Make --version show kernel version instead of pull req tag
  perf tools: Check if callchain is corrupted
  perf callchain: Make callchain cursors TLS
  ...

Pull drm intel and exynos fixes from Dave Airlie:
 "A bunch of fixes for Intel and exynos, nothing too major, a new intel
  PCI ID, and a fix for CRT detection."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
  char/agp: add another Ironlake host bridge
  drm/i915: fix up ivb plane 3 pageflips
  drm/exynos: fixed blending for hdmi graphic layer
  drm/exynos: Remove dummy encoder get_crtc operation implementation
  drm/exynos: Keep a reference to frame buffer GEM objects
  drm/exynos: Don't cast GEM object to Exynos GEM object when not needed
  drm/exynos: DRIVER_BUS_PLATFORM is not a driver feature
  drm/exynos: fixed size type.
  drm/exynos: Use DRM_FORMAT_{NV12, YUV420} instead of DRM_FORMAT_{NV12M, YUV420M}
  drm/i915: hold forcewake around ring hw init
  drm/i915: Mark the ringbuffers as being in the GTT domain
  drm/i915/crt: Do not rely upon the HPD presence pin
  drm/i915: Reset last_retired_head when resetting ring

Pull leap second timer fix from Thomas Gleixner.

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Fix CLOCK_MONOTONIC inconsistency during leapsecond

Merge tag 'moduleparam-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

Pull minor module param fixes from Rusty Russell:
 "One bugfix for multiple moduleparam levels, one removal of overzealous
  printk."

* tag 'moduleparam-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  init: Drop initcall level output
  module_param: stop double-calling parameters.

It was reported that compiling for 32-bit caused a bunch of
section mismatch warnings:

 VDSOSYM arch/x86/vdso/vdso32-syms.lds
  LD      arch/x86/vdso/built-in.o
  LD      arch/x86/built-in.o

 WARNING: arch/x86/built-in.o(.data+0x5af0): Section mismatch in
 reference from the variable test_nmi_ipi_callback_na.10451 to
 the function .init.text:test_nmi_ipi_callback() [...]

 WARNING: arch/x86/built-in.o(.data+0x5b04): Section mismatch in
 reference from the variable nmi_unk_cb_na.10399 to the function
 .init.text:nmi_unk_cb() The variable nmi_unk_cb_na.10399
 references the function __init nmi_unk_cb() [...]

Both of these are attributed to the internal representation of
the nmiaction struct created during register_nmi_handler.  The
reason for this is that those structs are not defined in the
init section whereas the rest of the code in nmi_selftest.c is.

To resolve this, I created a new #define,
register_nmi_handler_initonly, that tags the struct as
__initdata to resolve the mismatch.  This #define should only be
used in rare situations where the register/unregister is called
during init of the kernel.

Big thanks to Jan Beulich for decoding this for me as I didn't
have a clue what was going on.
Reported-by: NWitold Baryluk <baryluk@smp.if.uj.edu.pl>
Tested-by: NWitold Baryluk <baryluk@smp.if.uj.edu.pl>
Cc: Jan Beulich <JBeulich@suse.com>
Signed-off-by: NDon Zickus <dzickus@redhat.com>
Link: http://lkml.kernel.org/r/1338991542-23000-1-git-send-email-dzickus@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This fixes a problem which can causes kernel oopses while loading
a kernel module.

According to the PowerPC EABI specification, GPR r11 is assigned
the dedicated function to point to the previous stack frame.
In the powerpc-specific kernel module loader, do_plt_call()
(in arch/powerpc/kernel/module_32.c), GPR r11 is also used
to generate trampoline code.

This combination crashes the kernel, in the case where the compiler
chooses to use a helper function for saving GPRs on entry, and the
module loader has placed the .init.text section far away from the
.text section, meaning that it has to generate a trampoline for
functions in the .init.text section to call the GPR save helper.
Because the trampoline trashes r11, references to the stack frame
using r11 can cause an oops.

The fix just uses GPR r12 instead of GPR r11 for generating the
trampoline code.  According to the statements from Freescale, this is
safe from an EABI perspective.

I've tested the fix for kernel 2.6.33 on MPC8541.

Cc: stable@vger.kernel.org
Signed-off-by: NSteffen Rumler <steffen.rumler.ext@nsn.com>
[paulus@samba.org: reworded the description]
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The SGI Altix UV2 BAU (Broadcast Assist Unit) as used for
tlb-shootdown (selective broadcast mode) always uses UV2
broadcast descriptor format. There is no need to clear the
'legacy' (UV1) mode, because the hardware always uses UV2 mode
for selective broadcast.

But the BIOS uses general broadcast and legacy mode, and the
hardware pays attention to the legacy mode bit for general
broadcast. So the kernel must not clear that mode bit.
Signed-off-by: NCliff Wickman <cpw@sgi.com>
Cc: <stable@kernel.org>
Link: http://lkml.kernel.org/r/E1SccoO-0002Lh-Cb@eag09.americas.sgi.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

x86/mm: Only add extra pages count for the first memory range during pre-allocation early page table space

Robin found this regression:

| I just tried to boot an 8TB system.  It fails very early in boot with:
| Kernel panic - not syncing: Cannot find space for the kernel page tables

git bisect commit 722bc6b1.

A git revert of that commit does boot past that point on the 8TB
configuration.

That commit will add up extra pages for all memory range even
above 4g.

Try to limit that extra page count adding to first entry only.
Bisected-by: NRobin Holt <holt@sgi.com>
Tested-by: NRobin Holt <holt@sgi.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/CAE9FiQUj3wyzQxtq9yzBNc9u220p8JZ1FYHG7t%3DMOzJ%3D9BZMYA@mail.gmail.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

Merge branch 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung into drm-fixes

* 'exynos-drm-fixes' of git://git.infradead.org/users/kmpark/linux-samsung:
  drm/exynos: fixed blending for hdmi graphic layer
  drm/exynos: Remove dummy encoder get_crtc operation implementation
  drm/exynos: Keep a reference to frame buffer GEM objects
  drm/exynos: Don't cast GEM object to Exynos GEM object when not needed
  drm/exynos: DRIVER_BUS_PLATFORM is not a driver feature
  drm/exynos: fixed size type.
  drm/exynos: Use DRM_FORMAT_{NV12, YUV420} instead of DRM_FORMAT_{NV12M, YUV420M}

* 'drm-intel-fixes' of git://people.freedesktop.org/~danvet/drm-intel:
  drm/i915: pch_irq_handler -> {ibx, cpt}_irq_handler
  char/agp: add another Ironlake host bridge
  drm/i915: fix up ivb plane 3 pageflips
  drm/i915: hold forcewake around ring hw init
  drm/i915: Mark the ringbuffers as being in the GTT domain
  drm/i915/crt: Do not rely upon the HPD presence pin
  drm/i915: Reset last_retired_head when resetting ring

9fb48c74 ("params: add 3rd arg to option handler callback
signature") added similar lines to dmesg:

initlevel:0=early, 4 registered initcalls
initlevel:1=core, 31 registered initcalls
initlevel:2=postcore, 11 registered initcalls
initlevel:3=arch, 7 registered initcalls
initlevel:4=subsys, 40 registered initcalls
initlevel:5=fs, 30 registered initcalls
initlevel:6=device, 250 registered initcalls
initlevel:7=late, 35 registered initcalls

but they don't contain any info for the general user staring at dmesg.
I'm very doubtful the count of initcalls registered per level helps
anyone so drop that output completely.

Cc: Jim Cromie <jim.cromie@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jason Baron <jbaron@redhat.com>
Signed-off-by: NBorislav Petkov <borislav.petkov@amd.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Commit 026cee00 "params:
<level>_initcall-like kernel parameters" set old-style module
parameters to level 0.  And we call those level 0 calls where we used
to, early in start_kernel().

We also loop through the initcall levels and call the levelled
module_params before the corresponding initcall.  Unfortunately level
0 is early_init(), so we call the standard module_param calls twice.

(Turns out most things don't care, but at least ubi.mtd does).

Change the level to -1 for standard module_param calls.
Reported-by: NBenoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org

This reverts 68568add ("powerpc/time: Remove unnecessary sanity check
of decrementer expiration").  We do need to check whether we have reached
the expiration time of the next event, because we sometimes get an early
decrementer interrupt, most notably when we set the decrementer to 1 in
arch_irq_work_raise().  The effect of not having the sanity check is that
if timer_interrupt() gets called early, we leave the decrementer set to
its maximum value, which means we then don't get any more decrementer
interrupts for about 4 seconds (or longer, depending on timebase
frequency).  I saw these pauses as a consequence of getting a stray
hypervisor decrementer interrupt left over from exiting a KVM guest.

This isn't quite a straight revert because of changes to the surrounding
code, but it restores the same algorithm as was previously used.

Cc: stable@vger.kernel.org
Acked-by: NAnton Blanchard <anton@samba.org>
Acked-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This reverts commit 40af1bbd.

It's horribly and utterly broken for at least the following reasons:

 - calling sync_mm_rss() from mmput() is fundamentally wrong, because
   there's absolutely no reason to believe that the task that does the
   mmput() always does it on its own VM.  Example: fork, ptrace, /proc -
   you name it.

 - calling it *after* having done mmdrop() on it is doubly insane, since
   the mm struct may well be gone now.

 - testing mm against NULL before you call it is insane too, since a
NULL mm there would have caused oopses long before.

.. and those are just the three bugs I found before I decided to give up
looking for me and revert it asap.  I should have caught it before I
even took it, but I trusted Andrew too much.

Cc: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 79906964 uses the ext4_{set,clear}_inode_flags() functions to
change the i_flags automatically but fails to remove the error setting
of i_flags.  So we still have the problem of trashing state flags.
Fix this by removing the assignment.
Signed-off-by: NTao Ma <boyu.mt@taobao.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Cc: stable@kernel.org

Ext3 filesystems that are converted to use as many ext4 file system
features as possible will enable uninit_bg to speed up e2fsck times.
These file systems will have a native ext3 layout of inode tables and
block allocation bitmaps (as opposed to ext4's flex_bg layout).
Unfortunately, in these cases, when first allocating a block in an
uninitialized block group, ext4 would incorrectly calculate the number
of free blocks in that block group, and then errorneously report that
the file system was corrupt:

EXT4-fs error (device vdd): ext4_mb_generate_buddy:741: group 30, 32254 clusters in bitmap, 32258 in gd

This problem can be reproduced via:

    mke2fs -q -t ext4 -O ^flex_bg /dev/vdd 5g
    mount -t ext4 /dev/vdd /mnt
    fallocate -l 4600m /mnt/test

The problem was caused by a bone headed mistake in the check to see if a
particular metadata block was part of the block group.

Many thanks to Kees Cook for finding and bisecting the buggy commit
which introduced this bug (commit fd034a84, present since v3.2).
Reported-by: NSander Eikelenboom <linux@eikelenboom.it>
Reported-by: NKees Cook <keescook@chromium.org>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
Tested-by: NKees Cook <keescook@chromium.org>
Cc: stable@kernel.org

Merge random fixes from Andrew Morton.

* emailed from Andrew Morton <akpm@linux-foundation.org>: (11 patches)
  mm: correctly synchronize rss-counters at exit/exec
  btree: catch NULL value before it does harm
  btree: fix tree corruption in btree_get_prev()
  ipc: shm: restore MADV_REMOVE functionality on shared memory segments
  drivers/platform/x86/acerhdf.c: correct Boris' mail address
  c/r: prctl: drop VMA flags test on PR_SET_MM_ stack data assignment
  c/r: prctl: add ability to get clear_tid_address
  c/r: prctl: add minimal address test to PR_SET_MM
  c/r: prctl: update prctl_set_mm_exe_file() after mm->num_exe_file_vmas removal
  MAINTAINERS: whitespace fixes
  shmem: replace_page must flush_dcache and others

mm->rss_stat counters have per-task delta: task->rss_stat.  Before
changing task->mm pointer the kernel must flush this delta with
sync_mm_rss().

do_exit() already calls sync_mm_rss() to flush the rss-counters before
committing the rss statistics into task->signal->maxrss, taskstats,
audit and other stuff.  Unfortunately the kernel does this before
calling mm_release(), which can call put_user() for processing
task->clear_child_tid.  So at this point we can trigger page-faults and
task->rss_stat becomes non-zero again.  As a result mm->rss_stat becomes
inconsistent and check_mm() will print something like this:

| BUG: Bad rss-counter state mm:ffff88020813c380 idx:1 val:-1
| BUG: Bad rss-counter state mm:ffff88020813c380 idx:2 val:1

This patch moves sync_mm_rss() into mm_release(), and moves mm_release()
out of do_exit() and calls it earlier.  After mm_release() there should
be no pagefaults.

[akpm@linux-foundation.org: tweak comment]
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Reported-by: NMarkus Trippelsdorf <markus@trippelsdorf.de>
Cc: Hugh Dickins <hughd@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: <stable@vger.kernel.org>		[3.4.x]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Storing NULL values in the btree is illegal and can lead to memory
corruption and possible other fun as well.  Catch it on insert, instead
of waiting for the inevitable.
Signed-off-by: NJoern Engel <joern@logfs.org>
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The memory the parameter __key points to is used as an iterator in
btree_get_prev(), so if we save off a bkey() pointer in retry_key and
then assign that to __key, we'll end up corrupting the btree internals
when we do eg

	longcpy(__key, bkey(geo, node, i), geo->keylen);

to return the key value.  What we should do instead is use longcpy() to
copy the key value that retry_key points to __key.

This can cause a btree to get corrupted by seemingly read-only
operations such as btree_for_each_safe.

[akpm@linux-foundation.org: avoid the double longcpy()]
Signed-off-by: NRoland Dreier <roland@purestorage.com>
Acked-by: NJoern Engel <joern@logfs.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 17cf28af ("mm/fs: remove truncate_range") removed the
truncate_range inode operation in favour of the fallocate file
operation.

When using SYSV IPC shared memory segments, calling madvise with the
MADV_REMOVE advice on an area of shared memory will attempt to invoke
the .fallocate function for the shm_file_operations, which is NULL and
therefore returns -EOPNOTSUPP to userspace.  The previous behaviour
would inherit the inode_operations from the underlying tmpfs file and
invoke truncate_range there.

This patch restores the previous behaviour by wrapping the underlying
fallocate function in shm_fallocate, as we do for fsync.

[hughd@google.com: use -ENOTSUPP in shm_fallocate()]
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Acked-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NHugh Dickins <hughd@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Correct mail address reference to a mail account which I actually read.
Signed-off-by: NBorislav Petkov <bp@alien8.de>
Cc: Peter Feuerer <peter@piie.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>