when run the folloing command under shell, it will return error

  sh/$ echo 1 > /proc/sys/vm/compact_memory
  sh/$ sh: write error: Bad address

After strace, I found the following log:

  ...
  write(1, "1\n", 2)               = 3
  write(1, "", 4294967295)         = -1 EFAULT (Bad address)
  write(2, "echo: write error: Bad address\n", 31echo: write error: Bad address
  ) = 31

This tells system return 3(COMPACT_COMPLETE) after write data to
compact_memory.

The fix is to make the system just return 0 instead 3(COMPACT_COMPLETE)
from sysctl_compaction_handler after compaction_nodes finished.
Signed-off-by: Jason Liu <r64343@freescale.com>
Suggested-by: David Rientjes <rientjes@google.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The memmove span covers from (next+1) to the end of the array, and the
index of next is (i+1), so the index of (next+1) is (i+2).  So the size
of remaining array elements is (type->cnt - (i + 2)).

Since the remaining elements of the memblock array are move forward by
one element and there is only one additional element caused by this bug.
So there won't be any write overflow here but read overflow.  It may
read one more element out of the array address if the array happens to
be full.  Commonly it doesn't matter at all but if the array happens to
be located at the end a memblock, it may cause a invalid read operation
for the physical address doesn't exist.

There are 2 *happens to be* here, so I think the probability is quite
low, I don't know if any guy is haunted by this bug before.

Mostly I think it's user-invisible.
Signed-off-by: Lin Feng <linfeng@cn.fujitsu.com>
Acked-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This was leading to a strange behaviour when using the fbcon driver on
top of this one: the letters were in the right order, but each letter
had a vertical symmetry.

This was because the addressing was right for the byte, but the
addressing of each individual bit was inverted.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Brian Lilly <brian@crystalfontz.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Thomas Petazzoni <thomas@free-electrons.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Hugh Dickins pointed out that migrate_misplaced_transhuge_page() does
not check page_count before migrating like base page migration and
khugepage.  He could not see why this was safe and he is right.

The potential impact of the bug is avoided due to the limitations of
NUMA balancing.  The page_mapcount() check ensures that only a single
address space is using this page and as THPs are typically private it
should not be possible for another address space to fault it in
parallel.  If the address space has one associated task then it's
difficult to have both a GUP pin and be referencing the page at the same
time.  If there are multiple tasks then a buggy scenario requires that
another thread be accessing the page while the direct IO is in flight.
This is dodgy behaviour as there is a possibility of corruption with or
without THP migration.  It would be

While we happen to be safe for the most part it is shoddy to depend on
such "safety" so this patch checks the page count similar to anonymous
pages.  Note that this does not mean that the page_mapcount() check can
go away.  If we were to remove the page_mapcount() check the the THP
would have to be unmapped from all referencing PTEs, replaced with
migration PTEs and restored properly afterwards.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix the warning

  WARNING: drivers/rtc/rtc-da9055.o(.text+0xa71): Section mismatch in reference from the function da9055_rtc_probe() to the function .init.text:da9055_rtc_device_init()
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In some cases, free_irq_cpu_rmap() is called while holding a lock (eg
rtnl).  This can lead to deadlocks, because it invokes
flush_scheduled_work() which ends up waiting for whole system workqueue
to flush, but some pending works might try to acquire the lock we are
already holding.

This commit uses reference-counting to replace
irq_run_affinity_notifiers().  It also removes
irq_run_affinity_notifiers() altogether.

[akpm@linux-foundation.org: eliminate free_cpu_rmap, rename cpu_rmap_reclaim() to cpu_rmap_release(), propagate kref_put() retval from cpu_rmap_put()]
Signed-off-by: David Decotigny <decot@googlers.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: Amir Vadai <amirv@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc warnings in fs/seq_file.c:

  Warning(fs/seq_file.c:304): No description found for parameter 'whence'
  Warning(fs/seq_file.c:304): Excess function parameter 'origin' description in 'seq_lseek'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix kernel-doc warning in iov.c:

  Warning(drivers/pci/iov.c:752): No description found for parameter 'numvfs'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Sorry-by: Don Dutile <ddutile@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new kernel-doc warning in auditfilter.c:

  Warning(kernel/auditfilter.c:1157): Excess function parameter 'uid' description in 'audit_receive_filter'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Eric Paris <eparis@redhat.com>
Cc: linux-audit@redhat.com (subscribers-only)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Fix new kernel-doc warnings in clnt.c:

  Warning(net/sunrpc/clnt.c:561): No description found for parameter 'flavor'
  Warning(net/sunrpc/clnt.c:561): Excess function parameter 'auth' description in 'rpc_clone_client_set_auth'
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull x86 platform driver bugfixes from Matthew Garrett.

* 'for_linus' of git://cavan.codon.org.uk/platform-drivers-x86:
  asus-laptop: Fix potential invalid pointer dereference
  Update MAINTAINERS entry
  asus-laptop: Do not call HWRS on init
  sony-laptop: fix SNC buffer calls when SN06 returns Integers
  samsung-laptop: Add quirk for broken acpi_video backlight on N250P
  acer-wmi: add Aspire 5741G touchpad toggle key
  acer-wmi: change to emit touchpad on off key
  acer-wmi: fix obj is NULL but dereferenced
  MAINTAINERS: change the mail address of acer-wmi/msi-laptop maintainer

Pull KVM bugfixes from Marcelo Tosatti.

* git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: use dynamic percpu allocations for shared msrs area
  KVM: PPC: Book3S HV: Fix compilation without CONFIG_PPC_POWERNV
  powerpc: Corrected include header path in kvm_para.h
  Add rcu user eqs exception hooks for async page fault

Merge tag 'trace-3.8-rc2-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing regression fix from Steven Rostedt:
 "A change that came in this merge window broke the writing to the
  trace_options file.  It causes garbage to be read during the compare
  of option names, and breaks setting options via the trace_options
  file, although options can still be set via the options/<option>
  files."

* tag 'trace-3.8-rc2-regression-fix' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Fix regression of trace_options file setting

Pull s390 patches from Martin Schwidefsky:
 "Add the finit_module system call, fix the irq statistics in
  /proc/stat, fix a s390dbf lockdep problem, a patch revert for a
  problem that is not 100% understood yet, and a few patches to
  fix warnings."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/pci: define read*_relaxed functions
  s390/topology: export cpu_topology
  s390/pm: export pm_power_off
  s390/pci: define isa_dma_bridge_buggy
  s390/3215: partially revert tty close handling fix
  s390/irq: count cpu restart events
  s390/irq: remove split irq fields from /proc/stat
  s390/irq: enable irq sum accounting for /proc/stat again
  s390/syscalls: wire up finit_module syscall
  s390/pci: remove dead code
  s390/smp: fix section mismatch for smp_add_present_cpu()
  s390/debug: Fix s390dbf lockdep problem in debug_(un)register_view()

The latest change to allow trace options to be set on the command
line also broke the trace_options file.

The zeroing of the last byte of the option name that is echoed into
the trace_option file was removed with the consolidation of some
of the code. The compare between the option and what was written to
the trace_options file fails because the string holding the data
written doesn't terminate with a null character.

A zero needs to be added to the end of the string copied from
user space.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

Pull ARM fixes from Russell King.

* 'fixes' of git://git.linaro.org/people/rmk/linux-arm:
  ARM: 7616/1: cache-l2x0: aurora: Use writel_relaxed instead of writel
  ARM: 7615/1: cache-l2x0: aurora: Invalidate during clean operation with WT enable
  ARM: 7614/1: mm: fix wrong branch from Cortex-A9 to PJ4b
  ARM: 7612/1: imx: Do not select some errata that depends on !ARCH_MULTIPLATFORM
  ARM: 7611/1: VIC: fix bug in VIC irqdomain code
  ARM: 7610/1: versatile: bump IRQ numbers
  ARM: 7609/1: disable errata work-arounds which access secure registers
  ARM: 7608/1: l2x0: Only set .set_debug on PL310 r3p0 and earlier

Pull EDAC fixes from Borislav Petkov:
 "Two error path fixes causing a crash and a Kconfig fix for an issue
  which spilled all EDAC suboptions into the 'Device Drivers' menu."

* tag 'edac_fixes_for_3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/bp/bp:
  EDAC: Cleanup device deregistering path
  EDAC: Fix EDAC Kconfig menu
  EDAC: Fix kernel panic on module unloading

The check for a pmd being in the process of being split was dropped by
mistake by commit d10e63f2 ("mm: numa: Create basic numa page
hinting infrastructure"). Put it back.
Reported-by: Dave Jones <davej@redhat.com>
Debugged-by: Hillf Danton <dhillf@gmail.com>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Kirill Shutemov <kirill@shutemov.name>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 3a50597d ("KEYS: Make the session and process keyrings
per-thread") removed the definition of the thread_group_cred structure,
but left a now unused pointer in struct cred.
Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ARM SoC fixes from Olof Johansson:
 "People are back from the holiday breaks, and it shows.  Here are a
  bunch of fixes for a number of platforms:
   - A couple of small fixes for Nomadik
   - A larger set of changes for kirkwood/mvebu
     - uart driver selection, dt clocks, gpio-poweroff fixups, a few
       __init annotation fixes and some error handling improvement in
       their xor dma driver.
   - i.MX had a couple of minor fixes (and a critical one for flexcan2
     clock setup)
   - MXS has a small board fix and a framebuffer bugfix
   - A set of fixes for Samsung Exynos, fixing default bootargs and some
     Exynos5440 clock issues
   - A set of OMAP changes including PM fixes and a few sparse warning
     fixups

  All in all a bit more positive code delta than we'd ideally want to
  see here, mostly from the OMAP PM changes, but nothing overly crazy."

* tag 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (44 commits)
  ARM: clps711x: Fix bad merge of clockevents setup
  ARM: highbank: save and restore L2 cache and GIC on suspend
  ARM: highbank: add a power request clear
  ARM: highbank: fix secondary boot and hotplug
  ARM: highbank: fix typos with hignbank in power request functions
  ARM: dts: fix highbank cpu mpidr values
  ARM: dts: add device_type prop to cpu nodes on Calxeda platforms
  ARM: mx5: Fix MX53 flexcan2 clock
  ARM: OMAP2+: am33xx-hwmod: Fix wrongly terminated am33xx_usbss_mpu_irqs array
  pinctrl: mvebu: make pdma clock on dove mandatory
  ARM: Dove: Add pinctrl clock to DT
  dma: mv_xor: fix error handling for clocks
  dma: mv_xor: fix error handling of mv_xor_channel_add()
  arm: mvebu: Add missing ; for cpu node.
  arm: mvebu: Armada XP MV78230 has only three Ethernet interfaces
  arm: mvebu: Armada XP MV78230 has two cores, not one
  clk: mvebu: Remove inappropriate __init tagging
  ARM: Kirkwood: Use fixed-regulator instead of board gpio call
  ARM: Kirkwood: Fix missing sdio clock
  ARM: Kirkwood: Switch TWSI1 of 88f6282 to DT clock providers
  ...

Pull drm update from Dave Airlie:
 "Exynos and Radeon mostly, with a dma-buf and ttm fix thrown in.

  It's a bit big but its mostly exynos license fix ups and I'd rather
  not hold those up since its legally stuff.

  Radeon has a couple of fixes from dma engine work, TTM is just a
  locking fix, and dma-buf fix has been hanging around and I finally got
  a chance to review it."

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (30 commits)
  drm/ttm: fix fence locking in ttm_buffer_object_transfer
  drm/prime: drop reference on imported dma-buf come from gem
  drm/radeon: add quirk for d3 delay during switcheroo poweron for apple macbooks
  drm/exynos: move finish page flip to a common place
  drm/exynos: fimd: modify condition in fimd resume
  drm/radeon: fix DMA CS parser for r6xx linear copy packet
  drm/radeon: split r6xx and r7xx copy_dma functions
  drm/exynos: Use devm_clk_get in exynos_drm_gsc.c
  drm/exynos: Remove redundant NULL check in exynos_drm_gsc.c
  drm/exynos: Remove explicit freeing using devm_* APIs in exynos_drm_gsc.c
  drm/exynos: Use devm_clk_get in exynos_drm_rotator.c
  drm/exynos: Remove redundant NULL check in exynos_drm_rotator.c
  drm/exynos: Remove unnecessary devm_* freeing APIs in exynos_drm_rotator.c
  drm/exynos: Use devm_clk_get in exynos_drm_fimc.c
  drm/exynos: Remove redundant NULL check
  drm/exynos: Remove explicit freeing using devm_* APIs in exynos_drm_fimc.c
  drm/exynos: Use devm_kzalloc in exynos_drm_ipp.c
  drm/exynos: fix gem buffer allocation type checking
  drm/exynos: remove needless parenthesis.
  drm/exynos: fix incorrect interrupt induced by m2m operation.
  ...

Merge tag 'omap-for-v3.8-rc2/fixes-signed-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into fixes

From Tony Lindgren:
The biggest change is a fix to deal with different power state
on omap2 registers that causes issues trying to use common PM code.
Also fix few incorrect registers, and an issue for omap1 USB, and
few sparse fixes for issues that sneaked in with all the clean-up.

* tag 'omap-for-v3.8-rc2/fixes-signed-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap:
  ARM: OMAP2+: am33xx-hwmod: Fix wrongly terminated am33xx_usbss_mpu_irqs array
  ARM: OMAP1: fix USB configuration use-after-release
  ARM: OMAP2/3: PRM: fix bogus OMAP2xxx powerstate return values
  ARM: OMAP3: clock data: Add missing enable/disable for EMU clock
  ARM: OMAP4: PRM: Correct wrong instance usage for reading reset sources
  ARM: OMAP4: PRM: fix RSTTIME and RSTST offsets
  ARM: OMAP4: PRM: Correct reset source map
  ARM: OMAP: SRAM: resolve sparse warnings
  ARM: OMAP AM33xx: hwmod data: resolve sparse warnings
  ARM: OMAP: 32k counter: resolve sparse warnings
Signed-off-by: Olof Johansson <olof@lixom.net>

Merge branch 'v3.8-samsung-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into fixes

From Kukjin Kim:
Most of them are EXYNOS5440 fixes which are for changing uart console,
cpu id (typo)  and silent complaining gpio error in kernel boot.

* 'v3.8-samsung-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung:
  ARM: EXYNOS: skip the clock initialization for exynos5440
  ARM: EXYNOS: enable PINCTRL for EXYNOS5440
  ARM: dts: use uart port1 for console on exynos4210-smdkv310
  ARM: dts: use uart port0 for console on exynos5440-ssdk5440
  ARM: SAMSUNG: fix the cpu id for EXYNOS5440
  ARM: EXYNOS: Revise HDMI resource size

From Shawn Guo:
I have to send one critical mxsfb fix through arm-soc, as FB maintainer
is unresponsive for quite a while.  People start complaining the missing
of such an important fix.

* tag 'mxs-fixes-3.8' of git://git.linaro.org/people/shawnguo/linux-2.6:
  video: mxsfb: fix crash when unblanking the display
  ARM: dts: imx23-olinuxino: Fix IOMUX settings

From Shawn Guo:

It includes one critical fix - wrong flexcan2 clock will hang system
when the port gets brought up.  The other two are non-critical fixes,
which are sent together here, since it's still early -rc stage.

* tag 'imx-fixes-3.8' of git://git.linaro.org/people/shawnguo/linux-2.6:
  ARM: mx5: Fix MX53 flexcan2 clock
  ARM: dts: imx31-bug: Fix manufacturer compatible string
  clk: imx: Remove 'clock-output-names' from the examples

Pull sound fixes from Takashi Iwai:
 "Nothing too exciting here, just a few regression and trivial fixes,
  and new quirks for HD-audio and USB-audio.

   - HD-audio mute LED mode enum fix
   - Fix kernel panic of Digidesign Mbox2 usb-audio quirk (which was new
     in 3.8-rc1)
   - Creative BT-D1 usb-audio quirk
   - mute LED fixup for HP Pavillion 17 laptop"

* tag 'sound-3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - add mute LED for HP Pavilion 17 (Realtek codec)
  ALSA: au88x0: fix incorrect left shift
  sound: oss/pas2: Fix possible access out of array
  ALSA: usb-audio: Fix kernel panic of Digidesign Mbox2 quirk
  ALSA: usb-audio: Add support for Creative BT-D1 via usb sound quirks
  ALSA: hda - Switch "On" and "Off" for "Mute-LED Mode" kcontrol

Pull networking fixes from David Miller:

 1) New sysctl ndisc_notify needs some documentation, from Hanns
    Frederic Sowa.

 2) Netfilter REJECT target doesn't set transport header of SKB
    correctly, from Mukund Jampala.

 3) Forcedeth driver needs to check for DMA mapping failures, from Larry
    Finger.

 4) brcmsmac driver can't use usleep_range while holding locks, use
    udelay instead.  From Niels Ole Salscheider.

 5) Fix unregister of netlink bridge multicast database handlers, from
    Vlad Yasevich and Rami Rosen.

 6) Fix checksum calculations in netfilter's ipv6 network prefix
    translation module.

 7) Fix high order page allocation failures in netfilter xt_recent, from
    Eric Dumazet.

 8) mac802154 needs to use netif_rx_ni() instead of netif_rx() because
    mac802154_process_data() can execute in process rather than
    interrupt context.  From Alexander Aring.

 9) Fix splice handling of MSG_SENDPAGE_NOTLAST, otherwise we elide one
    tcp_push() too many.  From Eric Dumazet and Willy Tarreau.

10) Fix skb->truesize tracking in XEN netfront driver, from Ian
    Campbell.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (46 commits)
  xen/netfront: improve truesize tracking
  ipv4: fix NULL checking in devinet_ioctl()
  tcp: fix MSG_SENDPAGE_NOTLAST logic
  net/ipv4/ipconfig: really display the BOOTP/DHCP server's address.
  ip-sysctl: fix spelling errors
  mac802154: fix NOHZ local_softirq_pending 08 warning
  ipv6: document ndisc_notify in networking/ip-sysctl.txt
  ath9k: Fix Kconfig for ATH9K_HTC
  netfilter: xt_recent: avoid high order page allocations
  netfilter: fix missing dependencies for the NOTRACK target
  netfilter: ip6t_NPT: fix IPv6 NTP checksum calculation
  bridge: add empty br_mdb_init() and br_mdb_uninit() definitions.
  vxlan: allow live mac address change
  bridge: Correctly unregister MDB rtnetlink handlers
  brcmfmac: fix parsing rsn ie for ap mode.
  brcmsmac: add copyright information for Canonical
  rtlwifi: rtl8723ae: Fix warning for unchecked pci_map_single() call
  rtlwifi: rtl8192se: Fix warning for unchecked pci_map_single() call
  rtlwifi: rtl8192de: Fix warning for unchecked pci_map_single() call
  rtlwifi: rtl8192ce: Fix warning for unchecked pci_map_single() call
  ...

Use dynamic percpu allocations for the shared msrs structure,
to avoid using the limited reserved percpu space.
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Just map the read*_relaxed() functions to their corresponding read*() functions.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Export cpu_topology symbol, so it's available for modules.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Export pm_power_off symbol. Needed by at least one of the new device
drivers that come with CONFIG_PCI.
And all other architectures export that symbol as well.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Define isa_dma_bridge_buggy. Needed to make pci quirks compile:

drivers/pci/quirks.c: In function ‘quirk_isa_dma_hangs’:
drivers/pci/quirks.c:88:7: error: ‘isa_dma_bridge_buggy’ undeclared (first use in this function)
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Partially revert ae289dc1 "s390/3215: fix tty close handling", since this
leads sometimes to hanging agetty processes and therefore systems that get
stuck while starting.

This was magically fixed (bisected) by a common code patch from Alan Cox:
36b3c070 "tty: Move the handling of the tty release logic", however it was
unrelated.

Since the removed code worked for a decade, nobody knows anymore why it was
in there in the first place and debugging the observed hang is non-trivial
(at least for me :) ), let's just re-add the removed code before we see
other side effects.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

Count CPU Restart events and make them visible via /proc/interrupts.
Every CPU hotplug (online) event will increase the per cpu counter.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Now that irq sum accounting for /proc/stat's "intr" line works again we
have the oddity that the sum field (first field) contains only the sum
of the second (external irqs) and third field (I/O interrupts).
The reason for that is that these two fields are already sums of all other
fields. So if we would sum up everything we would count every interrupt
twice.
This is broken since the split interrupt accounting was merged two years
ago: 052ff461 "[S390] irq: have detailed
statistics for interrupt types".
To fix this remove the split interrupt fields from /proc/stat's "intr"
line again and only have them in /proc/interrupts.

This restores the old behaviour, seems to be the only sane fix and mimics
a behaviour from other architectures where /proc/interrupts also contains
more than /proc/stat's "intr" line does.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

For more than two years, since f2c66cd8
"/proc/stat: scalability of irq num per cpu" the output of /proc/stat is
broken.
The first field in the "intr" line should contain the sum of all interrupts,
however since the above mentioned change it is always zero.

The reason for that is that a per cpu irq sum variable had been introduced
which got incremented when calling kstat_incr_irqs_this_cpu(). However
on s390 we directly incremented only the per cpu per irq counter by accessing
the array element via kstat_cpu(smp_processor_id()).irqs[...].
So fix this and use the kstat_incr_irqs_this_cpu() wrapper which increments
both: the per cpu per irq counter and the per cpu irq sum counter.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>

Get rid of these:

arch/s390/pci/pci_dma.c:16:29: warning: ‘zpci_ioat_dt’ defined but not used [-Wunused-variable]
arch/s390/pci/pci.c:164:12: warning: ‘zpci_store_fib’ defined but not used [-Wunused-function]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Fixes this section mismatch:

WARNING: vmlinux.o(.text+0x145e4): Section mismatch in reference from the function
   smp_add_present_cpu() to the function .cpuinit.text:register_cpu()
The function smp_add_present_cpu() references
the function __cpuinit register_cpu().
This is often because smp_add_present_cpu lacks a __cpuinit
annotation or the annotation of register_cpu is wrong.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>