tasklet: ignore disabled tasklet in tasklet_action v2

v2 changes:
  - clear TASKLET_STATE_HI bit in tasklet_schedule
  - remove tasklet_hi_enable() as it is exactly the same as tasklet_enable()

Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

tasklet: ignore disabled tasklet in tasklet_action()

We met a ksoftirqd 100% issue, the perf top shows kernel is busy with
tasklet_action(), but no actual action is shown.  From dumped kernel,
there's only one disabled tasklet on the tasklet_vec.

tasklet_action might be handled after tasklet is disabled, this will make
disabled tasklet stayed on tasklet_vec.  tasklet_action will not handle
disabled tasklet, but place it on the tail of tasklet_vec, still raise
softirq for this tasklet.  Things will become worse if device driver uses
tasklet_disable on its device remove/close code.  The disabled tasklet
will stay on the vec, frequently __raise_softirq_off() and make ksoftirqd
wakeup even if no tasklets need to be handled.

This patch introduced a new TASKLET_STATE_HI bit to indicate HI_SOFTIRQ,
in tasklet_action(), simply ignore the disabled tasklet and don't raise
the softirq nr.  In my previous patch, I remove tasklet_hi_enable() since
it is the same as tasklet_enable().  So only tasklet_enable() needs to be
modified, if tasklet state is changed from disable to enable, use
__tasklet_schedule() to put it on the right vec.

Signed-off-by: Xiaotian Feng <dannyfeng@tencent.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drivers/tty/serial/serial_core.c: fix uart_get_attr_port() shift

drivers/tty/serial/serial_core.c: In function 'uart_get_attr_port':
drivers/tty/serial/serial_core.c:2412: warning: left shift count >= width of type

Cc: Greg KH <greg@kroah.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

h8300: select generic atomic64_t support

Rationales from Eric:

So I just looked a little deeper and it appears architectures that do
not support atomic64_t are broken.

The generic atomic64 support came in 2009 to support the perf subsystem
with the expectation that all architectures would implement atomic64
support.

Furthermore upon inspection of the kernel atomic64_t is used in a fair
number of places beyond the performance counters:

block/blk-cgroup.c
drivers/acpi/apei/
drivers/block/rbd.c
drivers/crypto/nx/nx.h
drivers/gpu/drm/radeon/radeon.h
drivers/infiniband/hw/ipath/
drivers/infiniband/hw/qib/
drivers/staging/octeon/
fs/xfs/
include/linux/perf_event.h
include/net/netfilter/nf_conntrack_acct.h
kernel/events/
kernel/trace/
net/mac80211/key.h
net/rds/

The block control group, infiniband, xfs, crypto, 802.11, netfilter.
Nothing quite so fundamental as fs/namespace.c but definitely in
multiplatform-code that should work, and is already broken on those
architecutres.

Looking at the implementation of atomic64_add_return in lib/atomic64.c the
code looks as efficient as these kinds of things get.

Which leads me to the conclusion that we need atomic64 support on all
architectures.

Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/pstore/ram.c: fix up section annotations

The compiler complained about missing section annotations.  Fix it.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Anton Vorontsov <cbouatmailru@gmail.com>
Cc: Colin Cross <ccross@android.com>
Acked-by: Kees Cook <keescook@chromium.org>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

time: don't inline EXPORT_SYMBOL functions

How is the compiler even handling exported functions that are marked
inline?  Anyway, these shouldn't be inline because of that, so remove that
marking.

Based on a larger patch by Mark Charlebois to get LLVM to build the
kernel.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Charlebois <mcharleb@qualcomm.com>
Cc: Paul Gortmaker <paul.gortmaker@windriver.com>
Cc: hank <pyu@redhat.com>
Cc: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

timeconst.pl: remove deprecated defined(@array)

The use of defined() on arrays and hashes has been deprecated since perl
5.6, but until 5.17.6 it only warned on lexicals, not package globals.

Signed-off-by: Dagfinn Ilmari Mannsåker <ilmari@ilmari.org>
Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

irq-tsk-comm-is-an-array-fix

remove comment, per David

Cc: Alan Cox <alan@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

irq: tsk->comm is an array

The array check is useless so remove it.

Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

drm/i915: optimize DIV_ROUND_CLOSEST() call

DIV_ROUND_CLOSEST is faster if the compiler knows it will only be dealing
with unsigned dividends.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: David Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

pcmcia: move unbind/rebind into dev_pm_ops.complete

Move the device rebind procedures for cardbus devices from the pm.resume
into the pm.complete callback.

The reason for moving the code is: "[...] The PM code needs to send
suspend and resume messages to every device in the right order, and it
can't do that if new devices are being added at the same time.  [...]"

However the situation really isn't quite that rigid.  In particular,
adding new children during a resume callback shouldn't cause much of
problem because the children don't need to be resumed anyway (since they
were never suspended).  On the other hand, if you do it you will get a
dev_warn() from the PM core, something like 'parent should not be
sleeping'.

Still, it is considered bad form and should be avoided if possible."

(Alan Stern's full comment about the topic can
be found here: <https://lkml.org/lkml/2012/7/10/254>)

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Greg KH <greg@kroah.com>
Acked-by: "Rafael J. Wysocki" <rjw@sisk.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/debugsfs: remove unnecessary inode->i_private initialization

inode->i_private is promised to be NULL on allocation, no need to set it
explicitly.

Signed-off-by: Yan Hong <clouds.yan@gmail.com>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

olpc: fix olpc-xo1-sci.c build errors

Fix build errors when CONFIG_INPUT=m.  This is not pretty, but all of the
OLPC kconfig options are bool instead of tristate.

arch/x86/built-in.o: In function `send_lid_state':
olpc-xo1-sci.c:(.text+0x1d323): undefined reference to `input_event'
olpc-xo1-sci.c:(.text+0x1d338): undefined reference to `input_event'
arch/x86/built-in.o: In function `free_ebook_switch':
olpc-xo1-sci.c:(.text+0x1d529): undefined reference to `input_unregister_device'
olpc-xo1-sci.c:(.text+0x1d533): undefined reference to `input_free_device'
arch/x86/built-in.o: In function `free_power_button':
olpc-xo1-sci.c:(.text+0x1d549): undefined reference to `input_unregister_device'
olpc-xo1-sci.c:(.text+0x1d553): undefined reference to `input_free_device'
arch/x86/built-in.o: In function `send_ebook_state':
olpc-xo1-sci.c:(.text+0x1d632): undefined reference to `input_event'
olpc-xo1-sci.c:(.text+0x1d647): undefined reference to `input_event'
arch/x86/built-in.o: In function `xo1_sci_intr':
olpc-xo1-sci.c:(.text+0x1d78e): undefined reference to `input_event'
olpc-xo1-sci.c:(.text+0x1d7a3): undefined reference to `input_event'
olpc-xo1-sci.c:(.text+0x1d7be): undefined reference to `input_event'
arch/x86/built-in.o:olpc-xo1-sci.c:(.text+0x1d7d3): more undefined references to `input_event' follow
arch/x86/built-in.o: In function `free_lid_switch':
olpc-xo1-sci.c:(.text+0x1d7fd): undefined reference to `input_unregister_device'
olpc-xo1-sci.c:(.text+0x1d807): undefined reference to `input_free_device'
arch/x86/built-in.o: In function `setup_lid_switch':
olpc-xo1-sci.c:(.devinit.text+0x155): undefined reference to `input_allocate_device'
olpc-xo1-sci.c:(.devinit.text+0x1a4): undefined reference to `input_register_device'
olpc-xo1-sci.c:(.devinit.text+0x1ce): undefined reference to `input_unregister_device'
olpc-xo1-sci.c:(.devinit.text+0x1d8): undefined reference to `input_free_device'
arch/x86/built-in.o: In function `xo1_sci_probe':
olpc-xo1-sci.c:(.devinit.text+0x235): undefined reference to `input_allocate_device'
olpc-xo1-sci.c:(.devinit.text+0x285): undefined reference to `input_register_device'
olpc-xo1-sci.c:(.devinit.text+0x299): undefined reference to `input_free_device'
olpc-xo1-sci.c:(.devinit.text+0x2e1): undefined reference to `input_register_device'
olpc-xo1-sci.c:(.devinit.text+0x2f5): undefined reference to `input_free_device'
olpc-xo1-sci.c:(.devinit.text+0x54c): undefined reference to `input_allocate_device'

In the long run, fixing this driver kconfig to be tristate instead of bool
would be a very good change.

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Andres Salomon <dilinger@queued.net>
Cc: Chris Ball <cjb@laptop.org>
Cc: Jon Nettleton <jon.nettleton@gmail.com>
Cc: Daniel Drake <dsd@laptop.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/x86/platform/uv: fix incorrect tlb flush all issue

The flush tlb optimization code has logical issue on UV platform.  It
doesn't flush the full range at all, since it simply ignores its 'end'
parameter (and hence also the "all" indicator) in uv_flush_tlb_others()
function.

Cliff's notes:

: I tested the patch on a UV.  It has the effect of either clearing 1 or all
: TLBs in a cpu.  I added some debugging to test for the cases when clearing
: all TLBs is overkill, and in practice it happens very seldom.

Reported-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Alex Shi <alex.shi@intel.com>
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Tested-by: Cliff Wickman <cpw@sgi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/x86/tools/insn_sanity.c: identify source of messages

The kernel build prints:

  Building modules, stage 2.
  TEST    posttest
  MODPOST 3821 modules
  TEST    posttest
Success: decoded and checked 1000000 random instructions with 0 errors (seed:0xaac4bc47)
  CC      arch/x86/boot/a20.o
  CC      arch/x86/boot/cmdline.o
  AS      arch/x86/boot/copy.o
  HOSTCC  arch/x86/boot/mkcpustr
  CC      arch/x86/boot/cpucheck.o
  CC      arch/x86/boot/early_serial_console.o

which is irritating because you don't know what program is proudly
pronouncing its success.

So, as described in "console mode programming user interface guidelines
version 101" which doesn't exist, change this program to identify the
source of its messages.

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

x86 numa: don't check if node is NUMA_NO_NODE

If we aren't debugging per_cpu maps, the cpu's node is stored in per_cpu
variable numa_node.  If `node' is NUMA_NO_NODE, it means the caller wants
to clear the cpu's node.  So we should also call set_cpu_numa_node() in
this case.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

arch/x86/platform/iris/iris.c: register a platform device and a platform driver

This makes the iris driver use the platform API, so it is properly exposed
in /sys.

[akpm@linux-foundation.org: remove commented-out code, add missing space to printk, clean up code layout]
Signed-off-by: Shérab <Sebastien.Hinderer@ens-lyon.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cpu_hotplug-unmap-cpu2node-when-the-cpu-is-hotremoved-fix

make acpi_unmap_lsapic __ref

Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

x86 cpu_hotplug: unmap cpu2node when the cpu is hotremoved

When a cpu is hotplugged, we call acpi_map_cpu2node() in
_acpi_map_lsapic() to store the cpu's node.  But we don't clear the cpu's
node in acpi_unmap_lsapic() when this cpu is hotremoved.  If the node is
also hotremoved, We will get the following messages:

[ 1646.771485] kernel BUG at include/linux/gfp.h:329!
[ 1646.828729] invalid opcode: 0000 [#1] SMP
[ 1646.877872] Modules linked in: ebtable_nat ebtables ipt_MASQUERADE iptable_nat nf_nat xt_CHECKSUM iptable_mangle bridge stp llc sunrpc ipt_REJECT nf_conntrack_ipv4 nf_defrag_ipv4 iptable_filter ip_tables ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter ip6_tables binfmt_misc dm_mirror dm_region_hash dm_log dm_mod vhost_net macvtap macvlan tun uinput iTCO_wdt iTCO_vendor_support coretemp kvm_intel kvm crc32c_intel microcode pcspkr i2c_i801 i2c_core lpc_ich mfd_core ioatdma e1000e i7core_edac edac_core sg acpi_memhotplug igb dca sd_mod crc_t10dif megaraid_sas mptsas mptscsih mptbase scsi_transport_sas scsi_mod
[ 1647.588773] Pid: 3126, comm: init Not tainted 3.6.0-rc3-tangchen-hostbridge+ #13 FUJITSU-SV PRIMEQUEST 1800E/SB
[ 1647.711545] RIP: 0010:[<ffffffff811bc3fd>]  [<ffffffff811bc3fd>] allocate_slab+0x28d/0x300
[ 1647.810492] RSP: 0018:ffff88078a049cf8  EFLAGS: 00010246
[ 1647.874028] RAX: 0000000000000000 RBX: 0000000000000001 RCX: 0000000000000000
[ 1647.959339] RDX: 0000000000000001 RSI: 0000000000000001 RDI: 0000000000000246
[ 1648.044659] RBP: ffff88078a049d38 R08: 00000000000040d0 R09: 0000000000000001
[ 1648.129953] R10: 0000000000000000 R11: 0000000000000b5f R12: 00000000000052d0
[ 1648.215259] R13: ffff8807c1417300 R14: 0000000000030038 R15: 0000000000000003
[ 1648.300572] FS:  00007fa9b1b44700(0000) GS:ffff8807c3800000(0000) knlGS:0000000000000000
[ 1648.397272] CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 1648.465985] CR2: 00007fa9b09acca0 CR3: 000000078b855000 CR4: 00000000000007e0
[ 1648.551265] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1648.636565] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 1648.721838] Process init (pid: 3126, threadinfo ffff88078a048000, task ffff8807bb6f2650)
[ 1648.818534] Stack:
[ 1648.842548]  ffff8807c39d7fa0 ffffffff000040d0 00000000000000bb 00000000000080d0
[ 1648.931469]  ffff8807c1417300 ffff8807c39d7fa0 ffff8807c1417300 0000000000000001
[ 1649.020410]  ffff88078a049d88 ffffffff811bc4a0 ffff8807c1410c80 0000000000000000
[ 1649.109464] Call Trace:
[ 1649.138713]  [<ffffffff811bc4a0>] new_slab+0x30/0x1b0
[ 1649.199075]  [<ffffffff811bc978>] __slab_alloc+0x358/0x4c0
[ 1649.264683]  [<ffffffff810b71c0>] ? alloc_fair_sched_group+0xd0/0x1b0
[ 1649.341695]  [<ffffffff811be7d4>] kmem_cache_alloc_node_trace+0xb4/0x1e0
[ 1649.421824]  [<ffffffff8109d188>] ? hrtimer_init+0x48/0x100
[ 1649.488414]  [<ffffffff810b71c0>] ? alloc_fair_sched_group+0xd0/0x1b0
[ 1649.565402]  [<ffffffff810b71c0>] alloc_fair_sched_group+0xd0/0x1b0
[ 1649.640297]  [<ffffffff810a8bce>] sched_create_group+0x3e/0x110
[ 1649.711040]  [<ffffffff810bdbcd>] sched_autogroup_create_attach+0x4d/0x180
[ 1649.793260]  [<ffffffff81089614>] sys_setsid+0xd4/0xf0
[ 1649.854694]  [<ffffffff8167a029>] system_call_fastpath+0x16/0x1b
[ 1649.926483] Code: 89 c4 e9 73 fe ff ff 31 c0 89 de 48 c7 c7 45 de 9e 81 44 89 45 c8 e8 22 05 4b 00 85 db 44 8b 45 c8 0f 89 4f ff ff ff 0f 0b eb fe <0f> 0b 90 eb fd 0f 0b eb fe 89 de 48 c7 c7 45 de 9e 81 31 c0 44
[ 1650.161454] RIP  [<ffffffff811bc3fd>] allocate_slab+0x28d/0x300
[ 1650.232348]  RSP <ffff88078a049cf8>
[ 1650.274029] ---[ end trace adf84c90f3fea3e5 ]---

The reason is that: the cpu's node is not NUMA_NO_NODE, we will call
alloc_pages_exact_node() to alloc memory on the node, but the node is
offlined.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

fs/block_dev.c: page cache wrongly left invalidated after revalidate_disk()

We found that bdev->bd_invalidated was left set once revalidate_disk() is
called, which results in page cache flush every time that device is open.

Specifically, we found this problem in MD block device.  Once we resize a
MD device, mdadm --monitor periodically flush all page cache for that
device every 60 or 1000 seconds when it opens the device.

This bug lies since at least 3.2.0 till the latest kernel(3.6.2).
Patch is attached.

The following steps will reproduce the problem.

1. prepair a block device(ex. /dev/sdb).
2. create two partitions.

sudo parted /dev/sdb
mklabel gpt
mkpart primary 0% 50%
mkpart primary 50% 100%

3. create a md device.

sudo mdadm -C /dev/md/hoge -l 1 -n 2 -e 1.2 --assume-clean --auto=md \
 --symlink=no /dev/sdb1 /dev/sdb2

4. create file system and mount it

sudo mkfs.ext3 /dev/md/hoge
sudo mkdir /mnt/test
sudo mount /dev/md/hoge /mnt/test

5. try to resize the device

sudo mdadm -G /dev/md/hoge --size=max

6. create a file to fill file cache.

sudo dd if=/dev/urandom of=/mnt/test/data bs=1M count=10
and verity the current status of file by free command.

7. mdadm monitor will open the md device every 1000 seconds
and you will find all file cache on the device are cleared.

The timing can be reduced by the following steps.

a) kill mdadm and restart it with --delay option
/sbin/mdadm --monitor --delay=30 --pid-file /var/run/mdadm/monitor.pid \
 --daemonise --scan --syslog

or open the md device directly.

sudo dd if=/dev/md/hoge of=/dev/null bs=4096 count=1

Signed-off-by: MITSUNARI Shigeo <herumi@nifty.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

vfs: d_obtain_alias() needs to use "/" as default name.

NFS appears to use d_obtain_alias() to create the root dentry rather than
d_make_root.  This can cause 'prepend_path()' to complain that the root
has a weird name if an NFS filesystem is lazily unmounted.  e.g.  if
"/mnt" is an NFS mount then

 { cd /mnt; umount -l /mnt ; ls -l /proc/self/cwd; }

will cause a WARN message like
   WARNING: at /home/git/linux/fs/dcache.c:2624 prepend_path+0x1d7/0x1e0()
   ...
   Root dentry has weird name <>

to appear in kernel logs.

So change d_obtain_alias() to use "/" rather than "" as the anonymous
name.

Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

selinux: fix sel_netnode_insert() suspicious rcu dereference

===============================
[ INFO: suspicious RCU usage. ]
3.5.0-rc1+ #63 Not tainted
-------------------------------
security/selinux/netnode.c:178 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 0
1 lock held by trinity-child1/8750:
 #0:  (sel_netnode_lock){+.....}, at: [<ffffffff812d8f8a>] sel_netnode_sid+0x16a/0x3e0

stack backtrace:
Pid: 8750, comm: trinity-child1 Not tainted 3.5.0-rc1+ #63
Call Trace:
 [<ffffffff810cec2d>] lockdep_rcu_suspicious+0xfd/0x130
 [<ffffffff812d91d1>] sel_netnode_sid+0x3b1/0x3e0
 [<ffffffff812d8e20>] ? sel_netnode_find+0x1a0/0x1a0
 [<ffffffff812d24a6>] selinux_socket_bind+0xf6/0x2c0
 [<ffffffff810cd1dd>] ? trace_hardirqs_off+0xd/0x10
 [<ffffffff810cdb55>] ? lock_release_holdtime.part.9+0x15/0x1a0
 [<ffffffff81093841>] ? lock_hrtimer_base+0x31/0x60
 [<ffffffff812c9536>] security_socket_bind+0x16/0x20
 [<ffffffff815550ca>] sys_bind+0x7a/0x100
 [<ffffffff816c03d5>] ? sysret_check+0x22/0x5d
 [<ffffffff810d392d>] ? trace_hardirqs_on_caller+0x10d/0x1a0
 [<ffffffff8133b09e>] ? trace_hardirqs_on_thunk+0x3a/0x3f
 [<ffffffff816c03a9>] system_call_fastpath+0x16/0x1b

This patch below does what Paul McKenney suggested in the previous thread.

Signed-off-by: Dave Jones <davej@redhat.com>
Reviewed-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: James Morris <jmorris@namei.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

CRIS: Fix I/O macros

The inb/outb macros for CRIS are broken from a number of points of view,
missing () around parameters and they have an unprotected if statement in
them.  This was breaking the compile of IPMI on CRIS and thus I was being
annoyed by build regressions, so I fixed them.

Plus I don't think they would have worked at all, since the data values
were missing "&" and the outsl had a "3" instead of a "4" for the size.
From what I can tell, this stuff is not used at all, so this can't be any
more broken than it was before, anyway.

Signed-off-by: Corey Minyard <cminyard@mvista.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Mikael Starvik <starvik@axis.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

proc: check vma->vm_file before dereferencing

7b540d0646ce ("proc_map_files_readdir(): don't bother with grabbing
files") switched proc_map_files_readdir() to use @f_mode directly instead of
grabbing @file reference, but same time the test for @vm_file presence was
lost leading to nil dereference.  The patch brings the test back.

The all proc_map_files feature is CONFIG_\10CHECKPOINT_RESTORE wrapped
(which is set to 'n' by default) so the bug doesn't affect regular
kernels.

The regression is 3.7-rc1 only as far as I can tell.

[gorcunov@openvz.org: provided changelog]
Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: vmscan: scale number of pages reclaimed by reclaim/compaction only in direct reclaim

Jiri Slaby reported the following:

(It's an effective revert of "mm: vmscan: scale number of pages
reclaimed by reclaim/compaction based on failures".)
Given kswapd had hours of runtime in ps/top output yesterday in the
morning and after the revert it's now 2 minutes in sum for the last 24h,
I would say, it's gone.

The intention of the patch in question was to compensate for the loss of
lumpy reclaim.  Part of the reason lumpy reclaim worked is because it
aggressively reclaimed pages and this patch was meant to be a sane
compromise.

When compaction fails, it gets deferred and both compaction and
reclaim/compaction is deferred avoid excessive reclaim.  However, since
commit c6543459 ("mm: remove __GFP_NO_KSWAPD"), kswapd is woken up each
time and continues reclaiming which was not taken into account when the
patch was developed.

As it is not taking deferred compaction into account in this path it scans
aggressively before falling out and making the compaction_deferred check
in compaction_ready.  This patch avoids kswapd scaling pages for reclaim
and leaves the aggressive reclaim to the process attempting the THP
allocation.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Reported-by: Jiri Slaby <jslaby@suse.cz>
Cc: Rik van Riel <riel@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Valdis Kletnieks <Valdis.Kletnieks@vt.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: fix a regression with HIGHMEM

Changeset 7f1290f2f2 ("mm: fix-up zone present pages") tried to fix a
issue when calculating zone->present_pages, but it causes a regression to
32bit systems with HIGHMEM.  With that changeset,
reset_zone_present_pages() resets all zone->present_pages to zero, and
fixup_zone_present_pages() is called to recalculate zone->present_pages
when the boot allocator frees core memory pages into the buddy allocator.
Because highmem pages are not freed by bootmem allocator, all highmem
zones' present_pages becomes zero.

Actually there's no need to recalculate present_pages for the highmem zone
because the bootmem allocator never allocates pages from it.  So fix the
regression by skipping highmem in function reset_zone_present_pages() and
fixup_zone_present_pages().

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Signed-off-by: Jianguo Wu <wujianguo@huawei.com>
Reported-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Tested-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan@kernel.org>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

doc: describe memcg swappiness more precisely

since fe35004f (mm: avoid swapping out with swappiness==0) memcg reclaim
stopped swapping out anon pages completely when 0 value is used.
Although this is somehow expected it hasn't been done for a really long
time this way and so it is probably better to be explicit about the
effect. Moreover global reclaim swapps out even when swappiness is 0
to prevent from OOM killer.

The original issue (a wrong tasks get killed in a small group and memcg
swappiness=0) has been reported on top of our 3.0 based kernel (with
fe35004f backported).  I have tried to replicate it by the test case
mentioned https://lkml.org/lkml/2012/10/10/223.

As David correctly pointed out (https://lkml.org/lkml/2012/10/10/418) the
significant role played the fact that all the processes in the group have
CAP_SYS_ADMIN but oom_score_adj has the similar effect.  Say there is 2G
of swap space which is 524288 pages.  If you add CAP_SYS_ADMIN bonus then
you have -15728 score for the bias.  This means that all tasks with less
than 60M get the minimum score and it is tasks ordering which determines
who gets killed as a result.

To summarize it.  Users of small groups (relatively to the swap size) with
CAP_SYS_ADMIN tasks resp.  oom_score_adj are affected the most others
might see an unexpected oom_badness calculation.  Whether this is a
workload which is representative, I don't know but I think that it is
worth fixing and pushing to stable as well.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Cc: David Rientjes <rientjes@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

memcg: oom: fix totalpages calculation for memory.swappiness==0

oom_badness() takes a totalpages argument which says how many pages are
available and it uses it as a base for the score calculation.  The value
is calculated by mem_cgroup_get_limit which considers both limit and
total_swap_pages (resp.  memsw portion of it).

This is usually correct but since fe35004f ("mm: avoid swapping out with
swappiness==0") we do not swap when swappiness is 0 which means that we
cannot really use up all the totalpages pages.  This in turn confuses oom
score calculation if the memcg limit is much smaller than the available
swap because the used memory (capped by the limit) is negligible comparing
to totalpages so the resulting score is too small if adj!=0 (typically
task with CAP_SYS_ADMIN or non zero oom_score_adj).  A wrong process might
be selected as result.

The problem can be worked around by checking mem_cgroup_swappiness==0 and
not considering swap at all in such a case.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: fix build warning for uninitialized value

do_wp_page() sets mmun_called if mmun_start and mmun_end were initialized
and, if so, may call mmu_notifier_invalidate_range_end() with these
values.  This doesn't prevent gcc from emitting a build warning though:

mm/memory.c: In function `do_wp_page':
mm/memory.c:2530: warning: `mmun_start' may be used uninitialized in this function
mm/memory.c:2531: warning: `mmun_end' may be used uninitialized in this function

It's much easier to initialize the variables to impossible values and do a
simple comparison to determine if they were initialized to remove the bool
entirely.

Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm: add anon_vma_lock to validate_mm()

Iterating over the vma->anon_vma_chain without anon_vma_lock may cause
NULL ptr deref in anon_vma_interval_tree_verify(), because the node in the
chain might have been removed.

[ 1523.657950] BUG: unable to handle kernel paging request at fffffffffffffff0
[ 1523.660022] IP: [<ffffffff8122c29c>] anon_vma_interval_tree_verify+0xc/0xa0
[ 1523.660022] PGD 4e28067 PUD 4e29067 PMD 0
[ 1523.675725] Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
[ 1523.750066] CPU 0
[ 1523.750066] Pid: 9050, comm: trinity-child64 Tainted: G        W    3.7.0-rc2-next-20121025-sasha-00001-g673f98e-dirty #77
[ 1523.750066] RIP: 0010:[<ffffffff8122c29c>]  [<ffffffff8122c29c>] anon_vma_interval_tree_verify+0xc/0xa0
[ 1523.750066] RSP: 0018:ffff880045f81d48  EFLAGS: 00010296
[ 1523.750066] RAX: 0000000000000000 RBX: fffffffffffffff0 RCX: 0000000000000000
[ 1523.750066] RDX: 0000000000000000 RSI: 0000000000000001 RDI: fffffffffffffff0
[ 1523.750066] RBP: ffff880045f81d58 R08: 0000000000000000 R09: 0000000000000f14
[ 1523.750066] R10: 0000000000000f12 R11: 0000000000000000 R12: ffff8800096c8d70
[ 1523.750066] R13: ffff8800096c8d00 R14: 0000000000000000 R15: ffff8800095b45e0
[ 1523.750066] FS:  00007f7a923f3700(0000) GS:ffff880013600000(0000) knlGS:0000000000000000
[ 1523.750066] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1523.750066] CR2: fffffffffffffff0 CR3: 000000000969d000 CR4: 00000000000406f0
[ 1523.750066] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1523.750066] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 1523.750066] Process trinity-child64 (pid: 9050, threadinfo ffff880045f80000, task ffff880048eb0000)
[ 1523.750066] Stack:
[ 1523.750066]  ffff88000d7533f0 fffffffffffffff0 ffff880045f81da8 ffffffff812361d8
[ 1523.750066]  ffff880045f81d98 ffff880048ee9000 ffff8800095b4580 ffff8800095b4580
[ 1523.750066]  ffff88001d1cdb00 ffff8800095b45f0 ffff880022a4d630 ffff8800095b45e0
[ 1523.750066] Call Trace:
[ 1523.750066]  [<ffffffff812361d8>] validate_mm+0x58/0x1e0
[ 1523.750066]  [<ffffffff81236aa5>] vma_adjust+0x635/0x6b0
[ 1523.750066]  [<ffffffff81236c81>] __split_vma.isra.22+0x161/0x220
[ 1523.750066]  [<ffffffff81237934>] split_vma+0x24/0x30
[ 1523.750066]  [<ffffffff8122ce6a>] sys_madvise+0x5da/0x7b0
[ 1523.750066]  [<ffffffff811cd14c>] ? rcu_eqs_exit+0x9c/0xb0
[ 1523.750066]  [<ffffffff811802cd>] ? trace_hardirqs_on+0xd/0x10
[ 1523.750066]  [<ffffffff83aee198>] tracesys+0xe1/0xe6
[ 1523.750066] Code: 4c 09 ff 48 39 ce 77 9e f3 c3 0f 1f 44 00 00 31 c0 c3 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 53
48 89 fb 48 83 ec 08 <48> 8b 17 48 8b 8a 90 00 00 00 48 39 4f 40 74 34 80 3d f7 1f 5c
[ 1523.750066] RIP  [<ffffffff8122c29c>] anon_vma_interval_tree_verify+0xc/0xa0
[ 1523.750066]  RSP <ffff880045f81d48>
[ 1523.750066] CR2: fffffffffffffff0
[ 1523.750066] ---[ end trace e35e5fa49072faf9 ]---

Figured out by Bob Liu.

Reported-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Bob Liu <lliubbo@gmail.com>
Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

tmpfs: change final i_blocks BUG to WARNING

Under a particular load on one machine, I have hit shmem_evict_inode()'s
BUG_ON(inode->i_blocks), enough times to narrow it down to a particular
race between swapout and eviction.

It comes from the "if (freed > 0)" asymmetry in shmem_recalc_inode(), and
the lack of coherent locking between mapping's nrpages and shmem's swapped
count.  There's a window in shmem_writepage(), between lowering nrpages in
shmem_delete_from_page_cache() and then raising swapped count, when the
freed count appears to be +1 when it should be 0, and then the asymmetry
stops it from being corrected with -1 before hitting the BUG.

One answer is coherent locking: using tree_lock throughout, without
info->lock; reasonable, but the raw_spin_lock in percpu_counter_add() on
used_blocks makes that messier than expected.  Another answer may be a
further effort to eliminate the weird shmem_recalc_inode() altogether, but
previous attempts at that failed.

So far undecided, but for now change the BUG_ON to WARN_ON: in usual
circumstances it remains a useful consistency check.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

tmpfs: fix shmem_getpage_gfp VM_BUG_ON

Fuzzing with trinity hit the "impossible" VM_BUG_ON(error) (which Fedora
has converted to WARNING) in shmem_getpage_gfp():

WARNING: at mm/shmem.c:1151 shmem_getpage_gfp+0xa5c/0xa70()
Pid: 29795, comm: trinity-child4 Not tainted 3.7.0-rc2+ #49
Call Trace:
 [<ffffffff8107100f>] warn_slowpath_common+0x7f/0xc0
 [<ffffffff8107106a>] warn_slowpath_null+0x1a/0x20
 [<ffffffff811903fc>] shmem_getpage_gfp+0xa5c/0xa70
 [<ffffffff81190e4f>] shmem_fault+0x4f/0xa0
 [<ffffffff8119f391>] __do_fault+0x71/0x5c0
 [<ffffffff811a2767>] handle_pte_fault+0x97/0xae0
 [<ffffffff811a4a39>] handle_mm_fault+0x289/0x350
 [<ffffffff816d091e>] __do_page_fault+0x18e/0x530
 [<ffffffff816d0ceb>] do_page_fault+0x2b/0x50
 [<ffffffff816cd3b8>] page_fault+0x28/0x30
 [<ffffffff816d5688>] tracesys+0xe1/0xe6

Thanks to Johannes for pointing to truncation: free_swap_and_cache() only
does a trylock on the page, so the page lock we've held since before
confirming swap is not enough to protect against truncation.

What cleanup is needed in this case?  Just delete_from_swap_cache(), which
takes care of the memcg uncharge.

Reported-by: Dave Jones <davej@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Merge branch 'akpm-current/current'

Merge remote-tracking branch 'drop-experimental/linux-next'

Conflicts:
drivers/net/ethernet/intel/Kconfig
drivers/ptp/Kconfig

Merge remote-tracking branch 'lzo-update/lzo-update'

Merge remote-tracking branch 'random/dev'

Merge remote-tracking branch 'clk/clk-next'

Merge remote-tracking branch 'signal/for-next'

Conflicts:
arch/arm/kernel/process.c
arch/sparc/kernel/sys_sparc_64.c

Merge remote-tracking branch 'dma-buf/for-next'

Merge remote-tracking branch 'pwm/for-next'

Merge remote-tracking branch 'dma-mapping/dma-mapping-next'

Merge remote-tracking branch 'kvmtool/master'

Merge remote-tracking branch 'tegra/for-next'

Merge remote-tracking branch 'samsung/for-next'

Merge remote-tracking branch 'renesas/next'

Merge remote-tracking branch 'ixp4xx/next'

Merge remote-tracking branch 'ep93xx/ep93xx-for-next'

Merge remote-tracking branch 'cortex/for-next'

Merge remote-tracking branch 'bcm2835/for-next'

Merge remote-tracking branch 'arm-soc/for-next'

Conflicts:
arch/arm/Kconfig
arch/arm/configs/afeb9260_defconfig
arch/arm/configs/stamp9g20_defconfig
arch/arm/mach-nomadik/board-nhk8815.c
arch/arm/mach-omap2/drm.c
arch/arm/mach-ux500/board-mop500-audio.c
arch/arm/mach-ux500/board-mop500.c
arch/arm/mach-ux500/cpu-db8500.c
drivers/net/ethernet/cadence/at91_ether.c
drivers/pinctrl/pinctrl-nomadik.c
drivers/tty/serial/atmel_serial.c

Merge remote-tracking branch 'gpio-lw/for-next'

Merge remote-tracking branch 'vhost/linux-next'

Conflicts:
drivers/net/tun.c

Merge remote-tracking branch 'pinctrl/for-next'

Conflicts:
arch/arm/boot/dts/spear1340.dtsi

Merge remote-tracking branch 'char-misc/char-misc-next'

Merge remote-tracking branch 'staging/staging-next'

Conflicts:
drivers/iio/adc/Kconfig
drivers/iio/adc/Makefile

Merge remote-tracking branch 'usb/usb-next'

Conflicts:
drivers/usb/early/ehci-dbgp.c
drivers/usb/musb/ux500.c

Merge remote-tracking branch 'tty/tty-next'

Conflicts:
drivers/tty/serial/omap-serial.c

Merge remote-tracking branch 'driver-core/driver-core-next'

Merge remote-tracking branch 'leds/for-next'

Merge remote-tracking branch 'regmap/for-next'

Merge remote-tracking branch 'drivers-x86/linux-next'

Merge remote-tracking branch 'workqueues/for-next'

Merge remote-tracking branch 'percpu/for-next'

Merge remote-tracking branch 'xen-two/linux-next'

Merge remote-tracking branch 'kvm-ppc/kvm-ppc-next'

Conflicts:
arch/powerpc/include/asm/Kbuild
arch/powerpc/include/uapi/asm/Kbuild
arch/powerpc/include/uapi/asm/epapr_hcalls.h

Merge remote-tracking branch 'kvm/linux-next'

Merge remote-tracking branch 'rcu/rcu/next'

Merge remote-tracking branch 'ftrace/for-next'

Merge remote-tracking branch 'tip/auto-latest'

Merge remote-tracking branch 'spi-mb/spi-next'

Merge remote-tracking branch 'dt-rh/for-next'

Merge remote-tracking branch 'edac-amd/for-next'

Merge remote-tracking branch 'edac/linux_next'

Merge remote-tracking branch 'fsnotify/for-next'

Conflicts:
kernel/audit_tree.c

Merge remote-tracking branch 'pm/linux-next'

Conflicts:
arch/x86/pci/acpi.c

Merge remote-tracking branch 'trivial/for-next'

Merge remote-tracking branch 'osd/linux-next'

Merge remote-tracking branch 'iommu/next'

Merge remote-tracking branch 'watchdog/master'

Merge remote-tracking branch 'selinux/master'

Merge remote-tracking branch 'security/next'

Conflicts:
fs/cifs/cifsacl.c
net/dns_resolver/dns_key.c
security/keys/keyctl.c
security/keys/keyring.c
security/keys/process_keys.c

Merge remote-tracking branch 'regulator/for-next'

Merge remote-tracking branch 'mfd/for-next'

Merge remote-tracking branch 'md/for-next'

Merge remote-tracking branch 'slab/for-next'

Conflicts:
mm/slob.c

Merge remote-tracking branch 'kgdb/kgdb-next'

Merge remote-tracking branch 'mmc/mmc-next'

Merge branch 'device-mapper/master'

Merge remote-tracking branch 'block/for-next'

Merge remote-tracking branch 'cgroup/for-next'

Merge remote-tracking branch 'input/next'

Merge remote-tracking branch 'virtio/virtio-next'

Merge remote-tracking branch 'modules/modules-next'

Merge remote-tracking branch 'sound-asoc/for-next'

Merge remote-tracking branch 'sound/for-next'

Merge remote-tracking branch 'drm/drm-next'

Merge remote-tracking branch 'crypto/master'

Merge remote-tracking branch 'l2-mtd/master'

Merge remote-tracking branch 'mtd/master'

Merge remote-tracking branch 'bluetooth/master'