Currently, some scan handlers can be compiled out entirely, which
leaves the device objects they normally attach to without a scan
handler.  This isn't a problem as long as we don't have any default
enumeration mechanism that applies to all devices without a scan
handler.  However, if such a default enumeration is added, it still
should not be applied to devices that are normally attached to by
scan handlers, because that may result in creating "physical" device
objects of a wrong type for them.

Since we are going to create platform device objects for all ACPI
device objects with pnp.type.platform_id set by default, clear
pnp.type.platform_id where there is a matching scan handler without
an .attach() callback and otherwise simply treat that scan handler
as though the .attach() callback was present but always returned 0.

This will allow us to compile out scan handler callbacks and leave
the device ID lists used by them so as to prevent creating platform
device objects for the matching ACPI devices.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Only certain types of ACPI device objects can be enumerated as
platform devices, so in order to distinguish them from the others
introduce a new ACPI device PNP type flag, platform_id, and set it
for devices with a valid _HID to start with.

This change is based on a Zhang Rui's prototype.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

The "serial" PNP driver supports some "unknown" PNP modems
(PNPCXXX/PNPDXXX) by matching magic strings in the PNP device name
or the PNP device card name.

ACPI enumerated PNP devices neither are PNP cards, nor have those
magic strings in device names, so this mechamism never actually works
for ACPI enumerated PNPCXXX/PNPDXXX devices.

Consequently, it is safe to remove those two IDs from the PNP ACPI scan
handler's device ID list.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

The PNP ACPI scan handler device ID list includes all the IDs from
all of the struct pnp_device_id instances in the tree, but some of
them do not follow the ACPI PNP ID rule (3 letters + 4 hex digits).

For those IDs, the coressponding devices will never be enumerated
via ACPI, so it is safe to remove them from the PNP ACPI ID list.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Subject and changelog]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

ACPI can be used to enumerate PNP devices, but the code does not
handle this in the right way currently.  Namely, if an ACPI device
object
 1. Has a _CRS method,
 2. Has an identification of
    "three capital characters followed by four hex digits",
 3. Is not in the excluded IDs list,
it will be enumerated to PNP bus (that is, a PNP device object will
be create for it).  This means that, actually, the PNP bus type is
used as the default bus type for enumerating _HID devices in ACPI.

However, more and more _HID devices need to be enumerated to the
platform bus instead (that is, platform device objects need to be
created for them).  As a result, the device ID list in acpi_platform.c
is used to enforce creating platform device objects rather than PNP
device objects for matching devices.  That list has been continuously
growing recently, unfortunately, and it is pretty much guaranteed to
grow even more in the future.

To address that problem it is better to enumerate _HID devices
as platform devices by default.  To this end, change the way of
enumerating PNP devices by adding a PNP ACPI scan handler that
will use a device ID list to create PNP devices for the ACPI
device objects whose device IDs are present in that list.

The initial device ID list in the PNP ACPI scan handler contains
all of the pnp_device_id strings from all the existing PNP drivers,
so this change should be transparent to the PNP core and all of the
PNP drivers.  Still, in the future it should be possible to reduce
its size by converting PNP drivers that need not be PNP for any
technical reasons into platform drivers.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
[rjw: Rewrote the changelog, modified the PNP ACPI scan handler code]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Introduce a .match() callback for ACPI scan handlers to allow them to
use more elaborate matching algorithms if necessary.  That is needed
for the upcoming PNP scan handler in particular.

This change is based on a Zhang Rui's prototype.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Pull AFS fixes and cleanups from David Howells:
 "Here are some patches to the AFS filesystem:

  1) Fix problems in the clean-up parts of the cache manager service
     handler.

  2) Split afs_end_call() introduced in (1) and replace some identical
     code elsewhere with a call to the first half of the split function.

  3) Fix an error introduced in the workqueue PREPARE_WORK() elimination
     commits.

  4) Clean up argument passing to functions called from the workqueue as
     there's now an insulating layer between them and the workqueue.
     This is possible from (3)"

* 'afs' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  AFS: Pass an afs_call* to call->async_workfn() instead of a work_struct*
  AFS: Fix kafs module unloading
  AFS: Part of afs_end_call() is identical to code elsewhere, so split it
  AFS: Fix cache manager service handlers

Merge documentation fixes from Randy Dunlap.

* emailed patches from Randy Dunlap <rdunlap@infradead.org>:
  Documentation: update /proc/stat "intr" count summary
  Documentation: update java sample wrapper for java 7
  Documentation: update thunderbird email client settings
  Documentation: fix typos in drm docbook

The sum at the beginning of line "intr" includes also unnumbered
interrupts.  It implies that the sum at the beginning isn't the sum
of the remainder of the line, not even an estimation.

Fixed the documentation to mention that.

This behaviour was added to /proc/stat in commit a2eddfa9 ("x86:
make /proc/stat account for all interrupts")
Signed-off-by: Jan Moskyto Matejka <mq@suse.cz>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The sample wrapper currently fails on some Java 7 .class files.  This
updates the wrapper to properly handle those files.
Signed-off-by: Jonathan Callen <jcallen@gentoo.org>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Added setting to email-clients that is easier to read and is easier to
setup thunderbird.  Removed config settings and added GUI settings.
Signed-off-by: Paul McQuade <paulmcquad@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix spelling typo in DocBook/drm.tmpl
Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull hwmon subsystem fixes from Jean Delvare.

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  hwmon: (ntc_thermistor) Fix OF device ID mapping
  hwmon: (ntc_thermistor) Fix dependencies
  hwmon: Document temp[1-*]_min_hyst sysfs attribute

Pull single scsi fix from James Bottomley:
 "This is a single fix for a bug exposed by a sysfs change in 3.13 which
  now causes libsas to trigger a warn on in device removal"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  [SCSI] scsi_transport_sas: move bsg destructor into sas_rphy_remove

Pull two nfsd bugfixes from Bruce Fields:
 "Just two bugfixes, one for a merge-window-introduced ACL regression,
  the other for a longer-standing v4 state bug"

* 'for-3.15' of git://linux-nfs.org/~bfields/linux:
  nfsd4: warn on finding lockowner without stateid's
  nfsd4: remove lockowner when removing lock stateid
  nfsd4: fix corruption on setting an ACL.

The mapping from OF device IDs to platform device IDs is wrong.
TYPE_NCPXXWB473 is 0, TYPE_NCPXXWL333 is 1, so
ntc_thermistor_id[TYPE_NCPXXWB473] is { "ncp15wb473", TYPE_NCPXXWB473 }
while
ntc_thermistor_id[TYPE_NCPXXWL333] is { "ncp18wb473", TYPE_NCPXXWB473 }.

So the name is wrong for all but the "ntc,ncp15wb473" entry, and the
type is wrong for the "ntc,ncp15wl333" entry.

So map the entries by index, it is neither elegant nor robust but at
least it is correct.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 9e8269de hwmon: (ntc_thermistor) Add DT with IIO support to NTC thermistor driver
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Cc: Doug Anderson <dianders@chromium.org>

In commit 9e8269de, support was added for ntc_thermistor devices being
declared in the device tree and implemented on top of IIO. With that
change, a dependency was added to the ntc_thermistor driver:

	depends on (!OF && !IIO) || (OF && IIO)

This construct has the drawback that the driver can no longer be
selected when OF is set and IIO isn't, nor when IIO is set and OF is
not. This is a regression for the original users of the driver.

As the new code depends on IIO and is useless without OF, include it
only if both are enabled, and set the dependencies accordingly. This
is clearer, more simple and more correct.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Fixes: 9e8269de hwmon: (ntc_thermistor) Add DT with IIO support to NTC thermistor driver
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Cc: Naveen Krishna Chatradhi <ch.naveen@samsung.com>
Cc: Doug Anderson <dianders@chromium.org>

The temp[1-*]_min_hyst sysfs attribute is already implemented by 3
hwmon drivers (adt7x10, lm77 and lm92) but was missing from the
standard interface.

Also add temp[1-*]_lcrit_hyst for consistency, even though no driver
implement that one for the time being.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>

This creates fractional divider type clock for the ones that
have it. It is needed by the UART driver as the clock rate must
accommodate to the requested baud rate.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

A power domain where we save the context of the additional
LPSS registers. We need to do this or all LPSS devices are
left in reset state when resuming from D3 on some Baytrails.
The devices with the fractional clock divider also have
zeros for N and M values after resuming unless they are
reset.

Li Aubrey found the root cause for the issue. The idea of
using power domain for LPSS came from Mika Westerberg.
Reported-by: Jin Yao <yao.jin@linux.intel.com>
Suggested-by: Li Aubrey <aubrey.li@linux.intel.com>
Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
[rjw: Added the .complete() callback to the PM domain, fixed build
 warning on 32-bit.]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

To seed up suspend and resume of devices included into Intel SoCs
handled by the ACPI LPSS driver during system suspend, make
acpi_lpss_create_device() call device_enable_async_suspend() for
every device created by it.

This requires acpi_create_platform_device() to be modified to return
a pointer to struct platform_device instead of an int.  As a result,
acpi_create_platform_device() cannot be pointed to by the .attach
pointer in platform_handler directly any more, so a simple wrapper
around it is necessary for this purpose.  That, in turn, allows the
second unused argument of acpi_create_platform_device() to be
dropped, which is an improvement.
Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Merge tag 'dmaengine-fixes-3.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine

Pull dmaengine fixes from Dan Williams:
 "Two fixes for -stable:

   - async_mult() sometimes maps less buffers than initially requested.
      We end up freeing dmaengine_unmap_data on an invalid pool.

   - mv_xor: register write ordering fix"

* tag 'dmaengine-fixes-3.15-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  dmaengine: fix dmaengine_unmap failure
  dma: mv_xor: Flush descriptors before activating a channel

Pull sparc fixes from David Miller:
 "A small bunch of bug fixes, in particular:

   1) On older cpus we need a different chunk of virtual address space
      to map the huge page TSB.

   2) Missing memory barrier in Niagara2 memcpy.

   3) trinity showed some places where fault validation was
      unnecessarily loud on sparc64

   4) Some sysfs printf's need a type adjustment, from Toralf Förster"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: fix format string mismatch in arch/sparc/kernel/sysfs.c
  sparc64: Add membar to Niagara2 memcpy code.
  sparc64: Fix huge TSB mapping on pre-UltraSPARC-III cpus.
  sparc64: Don't bark so loudly about 32-bit tasks generating 64-bit fault addresses.

Pull networking fixes from David Miller:
 "It looks like a sizeble collection but this is nearly 3 weeks of bug
  fixing while you were away.

   1) Fix crashes over IPSEC tunnels with NAT, the latter can reroute
      the packet through a non-IPSEC protected path and the code has to
      be able to handle SKBs attached to routes lacking an attached xfrm
      state.  From Steffen Klassert.

   2) Fix OOPSs in ipv4 and ipv6 ipsec layers for unsupported
      sub-protocols, also from Steffen Klassert.

   3) Set local_df on fragmented netfilter skbs otherwise we won't be
      able to forward successfully, from Florian Westphal.

   4) cdc_mbim ipv6 neighbour code does __vlan_find_dev_deep without
      holding RCU lock, from Bjorn Mork.

   5) local_df test in ip_may_fragment is inverted, from Florian
      Westphal.

   6) jme driver doesn't check for DMA mapping failures, from Neil
      Horman.

   7) qlogic driver doesn't calculate number of TX queues properly, from
      Shahed Shaikh.

   8) fib_info_cnt can drift irreversibly positive if we fail to
      allocate the fi->fib_metrics array, from Sergey Popovich.

   9) Fix use after free in ip6_route_me_harder(), also from Sergey
      Popovich.

  10) When SYSCTL is disabled, we don't handle local_port_range and
      ping_group_range defaults properly at all, from Cong Wang.

  11) Unaccelerated VLAN tagged frames improperly handled by cdc_mbim
      driver, fix from Bjorn Mork.

  12) cassini driver needs nested lock annotations for TX locking, from
      Emil Goode.

  13) On init error ipv6 VTI driver can unregister pernet ops twice,
      oops.  Fix from Mahtias Krause.

  14) If macvlan device is down, don't propagate IFF_ALLMULTI changes,
      from Peter Christensen.

  15) Missing NULL pointer check while parsing netlink config options in
      ip6_tnl_validate().  From Susant Sahani.

  16) Fix handling of neighbour entries during ipv6 router reachability
      probing, from Duan Jiong.

  17) x86 and s390 JIT address randomization has some address
      calculation bugs leading to crashes, from Alexei Starovoitov and
      Heiko Carstens.

  18) Clear up those uglies with nop patching and net_get_random_once(),
      from Hannes Frederic Sowa.

  19) Option length miscalculated in ip6_append_data(), fix also from
      Hannes Frederic Sowa.

  20) A while ago we fixed a race during device unregistry when a
      namespace went down, turns out there is a second place that needs
      similar protection.  From Cong Wang.

  21) In the new Altera TSE driver multicast filtering isn't working,
      disable it and just use promisc mode until the cause is found.
      From Vince Bridgers.

  22) When we disable router enabling in ipv6 we have to flush the
      cached routes explicitly, from Duan Jiong.

  23) NBMA tunnels should not cache routes on the tunnel object because
      the key is variable, from Timo Teräs.

  24) With stacked devices GRO information in skb->cb[] can be not setup
      properly, make sure it is in all code paths.  From Eric Dumazet.

  25) Really fix stacked vlan locking, multiple levels of nesting with
      intervening non-vlan devices are possible.  From Vlad Yasevich.

  26) Fallback ipip tunnel device's mtu is not setup properly, from
      Steffen Klassert.

  27) The packet scheduler's tcindex filter can crash because we
      structure copy objects with list_head's inside, oops.  From Cong
      Wang.

  28) Fix CHECKSUM_COMPLETE handling for ipv6 GRE tunnels, from Eric
      Dumazet.

  29) In some configurations 'itag' in __mkroute_input() can end up
      being used uninitialized because of how fib_validate_source()
      works.  Fix it by explitly initializing itag to zero like all the
      other fib_validate_source() callers do, from Li RongQing"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (116 commits)
  batman: fix a bogus warning from batadv_is_on_batman_iface()
  ipv4: initialise the itag variable in __mkroute_input
  bonding: Send ALB learning packets using the right source
  bonding: Don't assume 802.1Q when sending alb learning packets.
  net: doc: Update references to skb->rxhash
  stmmac: Remove unbalanced clk_disable call
  ipv6: gro: fix CHECKSUM_COMPLETE support
  net_sched: fix an oops in tcindex filter
  can: peak_pci: prevent use after free at netdev removal
  ip_tunnel: Initialize the fallback device properly
  vlan: Fix build error wth vlan_get_encap_level()
  can: c_can: remove obsolete STRICT_FRAME_ORDERING Kconfig option
  MAINTAINERS: Pravin Shelar is Open vSwitch maintainer.
  bnx2x: Convert return 0 to return rc
  bonding: Fix alb mode to only use first level vlans.
  bonding: Fix stacked device detection in arp monitoring
  macvlan: Fix lockdep warnings with stacked macvlan devices
  vlan: Fix lockdep warning with stacked vlan devices.
  net: Allow for more then a single subclass for netif_addr_lock
  net: Find the nesting level of a given device by type.
  ...

Pull scheduler fixes from Ingo Molnar:
 "The biggest commit is an irqtime accounting loop latency fix, the rest
  are misc fixes all over the place: deadline scheduling, docs, numa,
  balancer and a bad to-idle latency fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Initialize newidle balance stats in sd_numa_init()
  sched: Fix updating rq->max_idle_balance_cost and rq->next_balance in idle_balance()
  sched: Skip double execution of pick_next_task_fair()
  sched: Use CPUPRI_NR_PRIORITIES instead of MAX_RT_PRIO in cpupri check
  sched/deadline: Fix memory leak
  sched/deadline: Fix sched_yield() behavior
  sched: Sanitize irq accounting madness
  sched/docbook: Fix 'make htmldocs' warnings caused by missing description

Pull perf fixes from Ingo Molnar:
 "The biggest changes are fixes for races that kept triggering Trinity
  crashes, plus liblockdep build fixes and smaller misc fixes.

  The liblockdep bits in perf/urgent are a pull mistake - they should
  have been in locking/urgent - but by the time I noticed other commits
  were added and testing was done :-/ Sorry about that"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf: Fix a race between ring_buffer_detach() and ring_buffer_attach()
  perf: Prevent false warning in perf_swevent_add
  perf: Limit perf_event_attr::sample_period to 63 bits
  tools/liblockdep: Remove all build files when doing make clean
  tools/liblockdep: Build liblockdep from tools/Makefile
  perf/x86/intel: Fix Silvermont's event constraints
  perf: Fix perf_event_init_context()
  perf: Fix race in removing an event

Pull drm radeon and nouveau fixes from Dave Airlie:
 "Fixes for the other big two.

  The radeon VCE one is large but it fixes some userspace triggerable
  issues, otherwise its blackscreens and oopses.

  Nouveau fixes a bleeding laptop panel issue when displayport is used
  sometimes"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon/pm: don't allow debugfs/sysfs access when PX card is off (v2)
  drm/radeon: avoid segfault on device open when accel is not working.
  drm/radeon: fix typo in finding PLL params
  drm/radeon: fix register typo on si
  drm/radeon: fix buffer placement under memory pressure v2
  drm/radeon: fix page directory update size estimation
  drm/radeon: handle non-VGA class pci devices with ATRM
  drm/radeon: fix DCE83 check for mullins
  drm/radeon: check VCE relocation buffer range v3
  drm/radeon: also try GART for CPU accessed buffers
  drm/gf119-/disp: fix nasty bug which can clobber SOR0's clock setup
  drm/nvd9/therm: handle another kind of PWM fan

Merge misc fixes from Andrew Morton:
 "9 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  MAINTAINERS: add closing angle bracket to Vince Bridgers' email address
  Documentation: fix DOCBOOKS=... building
  ocfs2: fix double kmem_cache_destroy in dlm_init
  mm/memory-failure.c: fix memory leak by race between poison and unpoison
  wait: swap EXIT_ZOMBIE(Z) and EXIT_DEAD(X) chars in TASK_STATE_TO_CHAR_STR
  memcg: fix swapcache charge from kernel thread context
  mm: madvise: fix MADV_WILLNEED on shmem swapouts
  mm/filemap.c: avoid always dirtying mapping->flags on O_DIRECT
  hwpoison, hugetlb: lock_page/unlock_page does not match for handling a free hugepage

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Cc: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Prior to commit 42661299 ("[media] DocBook: Move all media docbook
stuff into its own directory") it was possible to build only a single
(or more) book(s) by calling, for example

    make htmldocs DOCBOOKS=80211.xml

This now fails:

    cp: target `.../Documentation/DocBook//media_api' is not a directory

Ignore errors from that copy to make this possible again.

Fixes: 42661299 ("[media] DocBook: Move all media docbook stuff into its own directory")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In dlm_init, if create dlm_lockname_cache failed in
dlm_init_master_caches, it will destroy dlm_lockres_cache which created
before twice.  And this will cause system die when loading modules.
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When a memory error happens on an in-use page or (free and in-use)
hugepage, the victim page is isolated with its refcount set to one.

When you try to unpoison it later, unpoison_memory() calls put_page()
for it twice in order to bring the page back to free page pool (buddy or
free hugepage list).  However, if another memory error occurs on the
page which we are unpoisoning, memory_failure() returns without
releasing the refcount which was incremented in the same call at first,
which results in memory leak and unconsistent num_poisoned_pages
statistics.  This patch fixes it.
Signed-off-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: <stable@vger.kernel.org>    [2.6.32+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In commit ad86622b ("wait: swap EXIT_ZOMBIE and EXIT_DEAD to hide
EXIT_TRACE from user-space") the order of task state definitions were
changed: EXIT_DEAD and EXIT_ZOMBIE were swapped.  Though the charterers
for the states in TASK_STATE_TO_CHAR_STR string were not updated.  This
patch synchronizes the string to the order of definitions.
Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 284f39af ("mm: memcg: push !mm handling out to page cache
charge function") explicitly checks for page cache charges without any
mm context (from kernel thread context[1]).

This seemed to be the only possible case where memory could be charged
without mm context so commit 03583f1a ("memcg: remove unnecessary
!mm check from try_get_mem_cgroup_from_mm()") removed the mm check from
get_mem_cgroup_from_mm().  This however caused another NULL ptr
dereference during early boot when loopback kernel thread splices to
tmpfs as reported by Stephan Kulow:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000360
  IP: get_mem_cgroup_from_mm.isra.42+0x2b/0x60
  Oops: 0000 [#1] SMP
  Modules linked in: btrfs dm_multipath dm_mod scsi_dh multipath raid10 raid456 async_raid6_recov async_memcpy async_pq raid6_pq async_xor xor async_tx raid1 raid0 md_mod parport_pc parport nls_utf8 isofs usb_storage iscsi_ibft iscsi_boot_sysfs arc4 ecb fan thermal nfs lockd fscache nls_iso8859_1 nls_cp437 sg st hid_generic usbhid af_packet sunrpc sr_mod cdrom ata_generic uhci_hcd virtio_net virtio_blk ehci_hcd usbcore ata_piix floppy processor button usb_common virtio_pci virtio_ring virtio edd squashfs loop ppa]
  CPU: 0 PID: 97 Comm: loop1 Not tainted 3.15.0-rc5-5-default #1
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
  Call Trace:
    __mem_cgroup_try_charge_swapin+0x40/0xe0
    mem_cgroup_charge_file+0x8b/0xd0
    shmem_getpage_gfp+0x66b/0x7b0
    shmem_file_splice_read+0x18f/0x430
    splice_direct_to_actor+0xa2/0x1c0
    do_lo_receive+0x5a/0x60 [loop]
    loop_thread+0x298/0x720 [loop]
    kthread+0xc6/0xe0
    ret_from_fork+0x7c/0xb0

Also Branimir Maksimovic reported the following oops which is tiggered
for the swapcache charge path from the accounting code for kernel threads:

  CPU: 1 PID: 160 Comm: kworker/u8:5 Tainted: P           OE 3.15.0-rc5-core2-custom #159
  Hardware name: System manufacturer System Product Name/MAXIMUSV GENE, BIOS 1903 08/19/2013
  task: ffff880404e349b0 ti: ffff88040486a000 task.ti: ffff88040486a000
  RIP: get_mem_cgroup_from_mm.isra.42+0x2b/0x60
  Call Trace:
    __mem_cgroup_try_charge_swapin+0x45/0xf0
    mem_cgroup_charge_file+0x9c/0xe0
    shmem_getpage_gfp+0x62c/0x770
    shmem_write_begin+0x38/0x40
    generic_perform_write+0xc5/0x1c0
    __generic_file_aio_write+0x1d1/0x3f0
    generic_file_aio_write+0x4f/0xc0
    do_sync_write+0x5a/0x90
    do_acct_process+0x4b1/0x550
    acct_process+0x6d/0xa0
    do_exit+0x827/0xa70
    kthread+0xc3/0xf0

This patch fixes the issue by reintroducing mm check into
get_mem_cgroup_from_mm.  We could do the same trick in
__mem_cgroup_try_charge_swapin as we do for the regular page cache path
but it is not worth troubles.  The check is not that expensive and it is
better to have get_mem_cgroup_from_mm more robust.

[1] - http://marc.info/?l=linux-mm&m=139463617808941&w=2

Fixes: 03583f1a ("memcg: remove unnecessary !mm check from try_get_mem_cgroup_from_mm()")
Reported-and-tested-by: Stephan Kulow <coolo@suse.com>
Reported-by: Branimir Maksimovic <branimir.maksimovic@gmail.com>
Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MADV_WILLNEED currently does not read swapped out shmem pages back in.

Commit 0cd6144a ("mm + fs: prepare for non-page entries in page
cache radix trees") made find_get_page() filter exceptional radix tree
entries but failed to convert all find_get_page() callers that WANT
exceptional entries over to find_get_entry().  One of them is shmem swap
readahead in madvise, which now skips over any swap-out records.

Convert it to find_get_entry().

Fixes: 0cd6144a ("mm + fs: prepare for non-page entries in page cache radix trees")
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In some testing I ran today (some fio jobs that spread over two nodes),
we end up spending 40% of the time in filemap_check_errors().  That
smells fishy.  Looking further, this is basically what happens:

blkdev_aio_read()
    generic_file_aio_read()
        filemap_write_and_wait_range()
            if (!mapping->nr_pages)
                filemap_check_errors()

and filemap_check_errors() always attempts two test_and_clear_bit() on
the mapping flags, thus dirtying it for every single invocation.  The
patch below tests each of these bits before clearing them, avoiding this
issue.  In my test case (4-socket box), performance went from 1.7M IOPS
to 4.0M IOPS.
Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>