The slab has just one free object, adding it to partial list head doesn't make
sense. And it can cause lock contentation. For example,
1. CPU takes the slab from partial list
2. fetch an object
3. switch to another slab
4. free an object, then the slab is added to partial list again
In this way n->list_lock will be heavily contended.
In fact, Alex had a hackbench regression. 3.1-rc1 performance drops about 70%
against 3.0. This patch fixes it.
Acked-by: Christoph Lameter <cl@linux.com>
Reported-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: Shaohua Li <shli@kernel.org>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

deactivate_slab() has the comparison if more than the minimum number of
partial pages are in the partial list wrong. An effect of this may be that
empty pages are not freed from deactivate_slab(). The result could be an
OOM due to growth of the partial slabs per node. Frees mostly occur from
__slab_free which is okay so this would only affect use cases where a lot
of switching around of per cpu slabs occur.

Switching per cpu slabs occurs with high frequency if debugging options are
enabled.
Reported-and-tested-by: Xiaotian Feng <xtfeng@gmail.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

The check_bytes() function is used by slub debugging.  It returns a pointer
to the first unmatching byte for a character in the given memory area.

If the character for matching byte is greater than 0x80, check_bytes()
doesn't work.  Becuase 64-bit pattern is generated as below.

	value64 = value | value << 8 | value << 16 | value << 24;
	value64 = value64 | value64 << 32;

The integer promotions are performed and sign-extended as the type of value
is u8.  The upper 32 bits of value64 is 0xffffffff in the first line, and
the second line has no effect.

This fixes the 64-bit pattern generation.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Matt Mackall <mpm@selenic.com>
Reviewed-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

When a slab is freed by __slab_free() and the slab can only contain a
single object ever then it was full (and therefore not on the partial
lists but on the full list in the debug case) before we reached
slab_empty.

This caused the following full list corruption when SLUB debugging was enabled:

  [ 5913.233035] ------------[ cut here ]------------
  [ 5913.233097] WARNING: at lib/list_debug.c:53 __list_del_entry+0x8d/0x98()
  [ 5913.233101] Hardware name: Adamo 13
  [ 5913.233105] list_del corruption. prev->next should be ffffea000434fd20, but was ffffea0004199520
  [ 5913.233108] Modules linked in: nfs fscache fuse ebtable_nat ebtables ppdev parport_pc lp parport ipt_MASQUERADE iptable_nat nf_nat nfsd lockd nfs_acl auth_rpcgss xt_CHECKSUM sunrpc iptable_mangle bridge stp llc cpufreq_ondemand acpi_cpufreq freq_table mperf ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ip6table_filter ip6_tables rfcomm bnep arc4 iwlagn snd_hda_codec_hdmi snd_hda_codec_idt snd_hda_intel btusb mac80211 snd_hda_codec bluetooth snd_hwdep snd_seq snd_seq_device snd_pcm usb_debug dell_wmi sparse_keymap cdc_ether usbnet cdc_acm uvcvideo cdc_wdm mii cfg80211 snd_timer dell_laptop videodev dcdbas snd microcode v4l2_compat_ioctl32 soundcore joydev tg3 pcspkr snd_page_alloc iTCO_wdt i2c_i801 rfkill iTCO_vendor_support wmi virtio_net kvm_intel kvm ipv6 xts gf128mul dm_crypt i915 drm_kms_helper drm i2c_algo_bit i2c_core video [last unloaded: scsi_wait_scan]
  [ 5913.233213] Pid: 0, comm: swapper Not tainted 3.0.0+ #127
  [ 5913.233213] Call Trace:
  [ 5913.233213]  <IRQ>  [<ffffffff8105df18>] warn_slowpath_common+0x83/0x9b
  [ 5913.233213]  [<ffffffff8105dfd3>] warn_slowpath_fmt+0x46/0x48
  [ 5913.233213]  [<ffffffff8127e7c1>] __list_del_entry+0x8d/0x98
  [ 5913.233213]  [<ffffffff8127e7da>] list_del+0xe/0x2d
  [ 5913.233213]  [<ffffffff814e0430>] __slab_free+0x1db/0x235
  [ 5913.233213]  [<ffffffff811706ab>] ? bvec_free_bs+0x35/0x37
  [ 5913.233213]  [<ffffffff811706ab>] ? bvec_free_bs+0x35/0x37
  [ 5913.233213]  [<ffffffff811706ab>] ? bvec_free_bs+0x35/0x37
  [ 5913.233213]  [<ffffffff81133085>] kmem_cache_free+0x88/0x102
  [ 5913.233213]  [<ffffffff811706ab>] bvec_free_bs+0x35/0x37
  [ 5913.233213]  [<ffffffff811706e1>] bio_free+0x34/0x64
  [ 5913.233213]  [<ffffffff813dc390>] dm_bio_destructor+0x12/0x14
  [ 5913.233213]  [<ffffffff8116fef6>] bio_put+0x2b/0x2d
  [ 5913.233213]  [<ffffffff813dccab>] clone_endio+0x9e/0xb4
  [ 5913.233213]  [<ffffffff8116f7dd>] bio_endio+0x2d/0x2f
  [ 5913.233213]  [<ffffffffa00148da>] crypt_dec_pending+0x5c/0x8b [dm_crypt]
  [ 5913.233213]  [<ffffffffa00150a9>] crypt_endio+0x78/0x81 [dm_crypt]

[ Full discussion here: https://lkml.org/lkml/2011/8/4/375 ]

Make sure that we remove such a slab also from the full lists.
Reported-and-tested-by: Dave Jones <davej@redhat.com>
Reported-and-tested-by: Xiaotian Feng <xtfeng@gmail.com>
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: Fix build with DEBUG_PAGEALLOC enabled.

Commit d006199e72a9 ("serial: sh-sci: Regtype probing doesn't need to be
fatal.") made sci_init_single() return when sci_probe_regmap() succeeds,
although it should return when sci_probe_regmap() fails.  This causes
systems using the serial sh-sci driver to crash during boot.

Fix the problem by using the right return condition.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The generic library code already exports the generic function, this was
left-over from the ARM-specific version that just got removed.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Since commit 1eb19a12 ("lib/sha1: use the git implementation of
SHA-1"), the ARM SHA1 routines no longer work.  The reason? They
depended on the larger 320-byte workspace, and now the sha1 workspace is
just 16 words (64 bytes).  So the assembly version would overwrite the
stack randomly.

The optimized asm version is also probably slower than the new improved
C version, so there's no reason to keep it around.  At least that was
the case in git, where what appears to be the same assembly language
version was removed two years ago because the optimized C BLK_SHA1 code
was faster.
Reported-and-tested-by: Joachim Eastwood <manabian@gmail.com>
Cc: Andreas Schwab <schwab@linux-m68k.org>
Cc: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

task->cred is declared as __rcu, and access to other tasks' ->cred is,
indeed, protected.  Access to current->cred does not need rcu_dereference()
at all, since only the task itself can change its ->cred.  sparse, of
course, has no way of knowing that...

Add force-cast in current_cred(), make current_fsuid() et.al. use it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Al points out that the do_follow_link() helper function really is
misnamed - it's about whether we should try to follow a symlink or not,
not about actually doing the following.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

After commit 3567866b: "RCUify freeing acls, let check_acl() go ahead in
RCU mode if acl is cached" posix_acl_permission is being called with an
unsupported flag and the permission check fails. This patch fixes the issue.
Signed-off-by: Ari Savolainen <ari.m.savolainen@gmail.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  ore: Make ore its own module
  exofs: Rename raid engine from exofs/ios.c => ore
  exofs: ios: Move to a per inode components & device-table
  exofs: Move exofs specific osd operations out of ios.c
  exofs: Add offset/length to exofs_get_io_state
  exofs: Fix truncate for the raid-groups case
  exofs: Small cleanup of exofs_fill_super
  exofs: BUG: Avoid sbi realloc
  exofs: Remove pnfs-osd private definitions
  nfs_xdr: Move nfs4_string definition out of #ifdef CONFIG_NFS_V4

The inode structure layout is largely random, and some of the vfs paths
really do care.  The path lookup in particular is already quite D$
intensive, and profiles show that accessing the 'inode->i_op->xyz'
fields is quite costly.

We already optimized the dcache to not unnecessarily load the d_op
structure for members that are often NULL using the DCACHE_OP_xyz bits
in dentry->d_flags, and this does something very similar for the inode
ops that are used during pathname lookup.

It also re-orders the fields so that the fields accessed by 'stat' are
together at the beginning of the inode structure, and roughly in the
order accessed.

The effect of this seems to be in the 1-2% range for an empty kernel
"make -j" run (which is fairly kernel-intensive, mostly in filename
lookup), so it's visible.  The numbers are fairly noisy, though, and
likely depend a lot on exact microarchitecture.  So there's more tuning
to be done.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Gcc tends to generate better code with small integers, including the
DCACHE_xyz flag tests - so move the common ones to be first in the list.
Also just remove the unused DCACHE_INOTIFY_PARENT_WATCHED and
DCACHE_AUTOFS_PENDING values, their users no longer exists in the source
tree.

And add a "unlikely()" to the DCACHE_OP_COMPARE test, since we want the
common case to be a nice straight-line fall-through.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net:
  net: Compute protocol sequence numbers and fragment IDs using MD5.
  crypto: Move md5_transform to lib/md5.c

Export everything from ore need exporting. Change Kbuild and Kconfig
to build ore.ko as an independent module. Import ore from exofs
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

ORE stands for "Objects Raid Engine"

This patch is a mechanical rename of everything that was in ios.c
and its API declaration to an ore.c and an osd_ore.h header. The ore
engine will later be used by the pnfs objects layout driver.

* File ios.c => ore.c

* Declaration of types and API are moved from exofs.h to a new
  osd_ore.h

* All used types are prefixed by ore_ from their exofs_ name.

* Shift includes from exofs.h to osd_ore.h so osd_ore.h is
  independent, include it from exofs.h.

Other than a pure rename there are no other changes. Next patch
will move the ore into it's own module and will export the API
to be used by exofs and later the layout driver
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

Exofs raid engine was saving on memory space by having a single layout-info,
single pid, and a single device-table, global to the filesystem. Then passing
a credential and object_id info at the io_state level, private for each
inode. It would also devise this contraption of rotating the device table
view for each inode->ino to spread out the device usage.

This is not compatible with the pnfs-objects standard, demanding that
each inode can have it's own layout-info, device-table, and each object
component it's own pid, oid and creds.

So: Bring exofs raid engine to be usable for generic pnfs-objects use by:

* Define an exofs_comp structure that holds obj_id and credential info.

* Break up exofs_layout struct to an exofs_components structure that holds a
  possible array of exofs_comp and the array of devices + the size of the
  arrays.

* Add a "comps" parameter to get_io_state() that specifies the ids creds
  and device array to use for each IO.

  This enables to keep the layout global, but the device-table view, creds
  and IDs at the inode level. It only adds two 64bit to each inode, since
  some of these members already existed in another form.

* ios raid engine now access layout-info and comps-info through the passed
  pointers. Everything is pre-prepared by caller for generic access of
  these structures and arrays.

At the exofs Level:

* Super block holds an exofs_components struct that holds the device
  array, previously in layout. The devices there are in device-table
  order. The device-array is twice bigger and repeats the device-table
  twice so now each inode's device array can point to a random device
  and have a round-robin view of the table, making it compatible to
  previous exofs versions.

* Each inode has an exofs_components struct that is initialized at
  load time, with it's own view of the device table IDs and creds.
  When doing IO this gets passed to the io_state together with the
  layout.

While preforming this change. Bugs where found where credentials with the
wrong IDs where used to access the different SB objects (super.c). As well
as some dead code. It was never noticed because the target we use does not
check the credentials.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

ios.c will be moving to an external library, for use by the
objects-layout-driver. Remove from it some exofs specific functions.

Also g_attr_logical_length is used both by inode.c and ios.c
move definition to the later, to keep it independent
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

In future raid code we will need to know the IO offset/length
and if it's a read or write to determine some of the array
sizes we'll need.

So add a new exofs_get_rw_state() API for use when
writeing/reading. All other simple cases are left using the
old way.

The major change to this is that now we need to call
exofs_get_io_state later at inode.c::read_exec and
inode.c::write_exec when we actually know these things. So this
patch is kept separate so I can test things apart from other
changes.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>

Computers have become a lot faster since we compromised on the
partial MD4 hash which we use currently for performance reasons.

MD5 is a much safer choice, and is inline with both RFC1948 and
other ISS generators (OpenBSD, Solaris, etc.)

Furthermore, only having 24-bits of the sequence number be truly
unpredictable is a very serious limitation.  So the periodic
regeneration and 8-bit counter have been removed.  We compute and
use a full 32-bit sequence number.

For ipv6, DCCP was found to use a 32-bit truncated initial sequence
number (it needs 43-bits) and that is fixed here as well.
Reported-by: Dan Kaminsky <dan@doxpara.com>
Tested-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

We are going to use this for TCP/IP sequence number and fragment ID
generation.
Signed-off-by: David S. Miller <davem@davemloft.net>

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: cope with negative dentries in cifs_get_root
  cifs: convert prefixpath delimiters in cifs_build_path_to_root
  CIFS: Fix missing a decrement of inFlight value
  cifs: demote DFS referral lookup errors to cFYI
  Revert "cifs: advertise the right receive buffer size to the server"

* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM / Runtime: Allow _put_sync() from interrupts-disabled context
  PM / Domains: Fix pm_genpd_poweron()

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86: (38 commits)
  acer-wmi: support Lenovo ideapad S205 wifi switch
  acerhdf.c: spaces in aliased changed to *
  platform-drivers-x86: ideapad-laptop: add missing ideapad_input_exit in ideapad_acpi_add error path
  x86 driver: fix typo in TDP override enabling
  Platform: fix samsung-laptop DMI identification for N150/N210/220/N230
  dell-wmi: Add keys for Dell XPS L502X
  platform-drivers-x86: samsung-q10: make dmi_check_callback return 1
  Platform: Samsung Q10 backlight driver
  platform-drivers-x86: intel_scu_ipc: convert to DEFINE_PCI_DEVICE_TABLE
  platform-drivers-x86: intel_rar_register: convert to DEFINE_PCI_DEVICE_TABLE
  platform-drivers-x86: intel_menlow: add missing return AE_OK for intel_menlow_register_sensor()
  platform-drivers-x86: intel_mid_thermal: fix memory leak
  platform-drivers-x86: msi-wmi: add missing sparse_keymap_free in msi_wmi_init error path
  Samsung Laptop platform driver: support N510
  asus-wmi: add uwb rfkill support
  asus-wmi: add gps rfkill support
  asus-wmi: add CWAP support and clarify the meaning of WAPF bits
  asus-wmi: return proper value in store_cpufv()
  asus-wmi: check for temp1 presence
  asus-wmi: add thermal sensor
  ...

* 'stable/bug.fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/trace: Fix compile error when CONFIG_XEN_PRIVILEGED_GUEST is not set
  xen: Fix misleading WARN message at xen_release_chunk
  xen: Fix printk() format in xen/setup.c
  xen/tracing: it looks like we wanted CONFIG_FTRACE
  xen/self-balloon: Add dependency on tmem.
  xen/balloon: Fix compile errors - missing header files.
  xen/grant: Fix compile warning.
  xen/pciback: remove duplicated #include

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6:
  Battery: sysfs_remove_battery(): possible circular locking

Two additional savage4 variants were added, but the S3_SAVAGE4_SERIES
macro was incompletely modified, resulting in a false positive detection
of a savage4 card regardless of which savage card is actually present.

For non-savage4 series cards, such as a Savage/IX-MV card, this results
in garbled video and/or a hard-hang at boot time.  Fix this by changing
an '||' to an '&&' in the S3_SAVAGE4_SERIES macro.
Signed-off-by: John P. Stanley <jpsinthemix@verizon.net>
Reviewed-by: Tormod Volden <debian.tormod@gmail.com>
[ The macros have incomplete parenthesis too, but whatever ..  -Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Patch reviewers now recommend not splitting long user-visible strings,
such as printk messages, even if they exceed 80 columns.  This avoids
breaking grep.  However, that recommendation did not actually appear
anywhere in Documentation/CodingStyle.

See, for example, the thread at
  http://news.gmane.org/find-root.php?message_id=%3c1312215262.11635.15.camel%40Joe%2dLaptop%3eSigned-off-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The CLOEXE bit is magical, and for performance (and semantic) reasons we
don't actually maintain it in the file descriptor itself, but in a
separate bit array.  Which means that when we show f_flags, the CLOEXE
status is shown incorrectly: we show the status not as it is now, but as
it was when the file was opened.

Fix that by looking up the bit properly in the 'fdt->close_on_exec' bit
array.

Uli needs this in order to re-implement the pfiles program:

  "For normal file descriptors (not sockets) this was the last piece of
   information which wasn't available.  This is all part of my 'give
   Solaris users no reason to not switch' effort.  I intend to offer the
   code to the util-linux-ng maintainers."
Requested-by: Ulrich Drepper <drepper@akkadia.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

WARN_ONCE() is very annoying, in that it shows the stack trace that we
don't care about at all, and also triggers various user-level "kernel
oopsed" logic that we really don't care about.  And it's not like the
user can do anything about the applications (sshd) in question, it's a
distro issue.

Requested-by: Andi Kleen <andi@firstfloor.org> (and many others)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

For ChromiumOS, we use SHA-1 to verify the integrity of the root
filesystem.  The speed of the kernel sha-1 implementation has a major
impact on our boot performance.

To improve boot performance, we investigated using the heavily optimized
sha-1 implementation used in git.  With the git sha-1 implementation, we
see a 11.7% improvement in boot time.

10 reboots, remove slowest/fastest.

Before:

  Mean: 6.58 seconds Stdev: 0.14

After (with git sha-1, this patch):

  Mean: 5.89 seconds Stdev: 0.07

The other cool thing about the git SHA-1 implementation is that it only
needs 64 bytes of stack for the workspace while the original kernel
implementation needed 320 bytes.
Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Cc: Nicolas Pitre <nico@cam.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: David S. Miller <davem@davemloft.net>
Cc: linux-crypto@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/sparc/mm/init_64.c:1622:22: error: unused variable '__swapper_4m_tsb_phys_patch_end' [-Werror=unused-variable]
arch/sparc/mm/init_64.c:1621:22: error: unused variable '__swapper_4m_tsb_phys_patch' [-Werror=unused-variable]
Signed-off-by: David S. Miller <davem@davemloft.net>

Commit 9c921c22
Author: Lan Tianyu <tianyu.lan@intel.com>

    ACPI / Battery: Resolve the race condition in the sysfs_remove_battery()

fixed BUG https://bugzilla.kernel.org/show_bug.cgi?id=35642 , but as a side
effect made lockdep unhappy with sysfs_remove_battery():

[14818.477168]
[14818.477170] =======================================================
[14818.477200] [ INFO: possible circular locking dependency detected ]
[14818.477221] 3.1.0-dbg-07865-g1280ea8-dirty #668
[14818.477236] -------------------------------------------------------
[14818.477257] s2ram/1599 is trying to acquire lock:
[14818.477276]  (s_active#8){++++.+}, at: [<ffffffff81169147>] sysfs_addrm_finish+0x31/0x5a
[14818.477323]
[14818.477325] but task is already holding lock:
[14818.477350]  (&battery->lock){+.+.+.}, at: [<ffffffffa0047278>] sysfs_remove_battery+0x10/0x4b [battery]
[14818.477395]
[14818.477397] which lock already depends on the new lock.
[14818.477399]
[..]
[14818.479121] stack backtrace:
[14818.479148] Pid: 1599, comm: s2ram Not tainted 3.1.0-dbg-07865-g1280ea8-dirty #668
[14818.479175] Call Trace:
[14818.479198]  [<ffffffff814828c3>] print_circular_bug+0x293/0x2a4
[14818.479228]  [<ffffffff81070cb5>] __lock_acquire+0xfe4/0x164b
[14818.479260]  [<ffffffff81169147>] ? sysfs_addrm_finish+0x31/0x5a
[14818.479288]  [<ffffffff810718d2>] lock_acquire+0x138/0x1ac
[14818.479316]  [<ffffffff81169147>] ? sysfs_addrm_finish+0x31/0x5a
[14818.479345]  [<ffffffff81168a79>] sysfs_deactivate+0x9b/0xec
[14818.479373]  [<ffffffff81169147>] ? sysfs_addrm_finish+0x31/0x5a
[14818.479405]  [<ffffffff81169147>] sysfs_addrm_finish+0x31/0x5a
[14818.479433]  [<ffffffff81167bc5>] sysfs_hash_and_remove+0x54/0x77
[14818.479461]  [<ffffffff811681b9>] sysfs_remove_file+0x12/0x14
[14818.479488]  [<ffffffff81385bf8>] device_remove_file+0x12/0x14
[14818.479516]  [<ffffffff81386504>] device_del+0x119/0x17c
[14818.479542]  [<ffffffff81386575>] device_unregister+0xe/0x1a
[14818.479570]  [<ffffffff813c6ef9>] power_supply_unregister+0x23/0x27
[14818.479601]  [<ffffffffa004729c>] sysfs_remove_battery+0x34/0x4b [battery]
[14818.479632]  [<ffffffffa004778f>] battery_notify+0x2c/0x3a [battery]
[14818.479662]  [<ffffffff8148fe82>] notifier_call_chain+0x74/0xa1
[14818.479692]  [<ffffffff810624b4>] __blocking_notifier_call_chain+0x6c/0x89
[14818.479722]  [<ffffffff810624e0>] blocking_notifier_call_chain+0xf/0x11
[14818.479751]  [<ffffffff8107e40e>] pm_notifier_call_chain+0x15/0x27
[14818.479770]  [<ffffffff8107ee1a>] enter_state+0xa7/0xd5
[14818.479782]  [<ffffffff8107e341>] state_store+0xaa/0xc0
[14818.479795]  [<ffffffff8107e297>] ? pm_async_store+0x45/0x45
[14818.479807]  [<ffffffff81248837>] kobj_attr_store+0x17/0x19
[14818.479820]  [<ffffffff81167e27>] sysfs_write_file+0x103/0x13f
[14818.479834]  [<ffffffff81109037>] vfs_write+0xad/0x13d
[14818.479847]  [<ffffffff811092b2>] sys_write+0x45/0x6c
[14818.479860]  [<ffffffff81492f92>] system_call_fastpath+0x16/0x1b

This patch introduces separate lock to struct acpi_battery to
grab in sysfs_remove_battery() instead of battery->lock.
So fix by Lan Tianyu is still there, we just grab independent lock.
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Tested-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

Currently the use of pm_runtime_put_sync() is not safe from
interrupts-disabled context because rpm_idle() will release the
spinlock and enable interrupts for the idle callbacks.  This enables
interrupts during a time where interrupts were expected to be
disabled, and can have strange side effects on drivers that expected
interrupts to be disabled.

This is not a bug since the documentation clearly states that only
_put_sync_suspend() is safe in IRQ-safe mode.

However, pm_runtime_put_sync() could be made safe when in IRQ-safe
mode by releasing the spinlock but not re-enabling interrupts, which
is what this patch aims to do.

Problem was found when using some buggy drivers that set
pm_runtime_irq_safe() and used _put_sync() in interrupts-disabled
context.
Reported-by: Colin Cross <ccross@google.com>
Tested-by: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

The local variable ret is defined twice in pm_genpd_poweron(), which
causes this function to always return 0, even if the PM domain's
.power_on() callback fails, in which case an error code should be
returned.

Remove the wrong second definition of ret and additionally remove an
unnecessary definition of wait from pm_genpd_poweron().
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

The AMW0 function in acer-wmi works on Lenovo ideapad S205 for control
the wifi hardware state. We also found there have a 0x78 EC register
exposes the state of wifi hardware switch on the machine.

So, add this patch to support Lenovo ideapad S205 wifi hardware switch
in acer-wmi driver.

Reference: bko#37892
	https://bugzilla.kernel.org/show_bug.cgi?id=37892

Cc: Carlos Corbacho <carlos@strangeworlds.co.uk>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Dmitry Torokhov <dtor@mail.ru>
Cc: Corentin Chary <corentincj@iksaif.net>
Cc: Thomas Renninger <trenn@suse.de>
Tested-by: Florian Heyer <heyho@flanto.de>
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>

It seems that aliases shouldn't contain spaces, as
module-init-tools uses them as delimeters in module.alias file
Signed-off-by: Anton V. Boyarshinov <boyarsh@altlinux.org>
Signed-off-by: Matthew Garrett <mjg@redhat.com>