Black-list kmem accounting policy (aka __GFP_NOACCOUNT) turned out to be
fragile and difficult to maintain, because there seem to be many more
allocations that should not be accounted than those that should be.
Besides, false accounting an allocation might result in much worse
consequences than not accounting at all, namely increased memory
consumption due to pinned dead kmem caches.

So this patch switches kmem accounting to the white-policy: now only
those kmem allocations that are marked as __GFP_ACCOUNT are accounted to
memcg.  Currently, no kmem allocations are marked like this.  The
following patches will mark several kmem allocations that are known to
be easily triggered from userspace and therefore should be accounted to
memcg.
Signed-off-by: NVladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 8f4fc071 ("gfp: add __GFP_NOACCOUNT").

Black-list kmem accounting policy (aka __GFP_NOACCOUNT) turned out to be
fragile and difficult to maintain, because there seem to be many more
allocations that should not be accounted than those that should be.
Besides, false accounting an allocation might result in much worse
consequences than not accounting at all, namely increased memory
consumption due to pinned dead kmem caches.

So it was decided to switch to the white-list policy.  This patch
reverts bits introducing the black-list policy.  The white-list policy
will be introduced later in the series.
Signed-off-by: NVladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Currently, all kmem allocations (namely every kmem_cache_alloc, kmalloc,
alloc_kmem_pages call) are accounted to memory cgroup automatically.
Callers have to explicitly opt out if they don't want/need accounting
for some reason.  Such a design decision leads to several problems:

 - kmalloc users are highly sensitive to failures, many of them
   implicitly rely on the fact that kmalloc never fails, while memcg
   makes failures quite plausible.

 - A lot of objects are shared among different containers by design.
   Accounting such objects to one of containers is just unfair.
   Moreover, it might lead to pinning a dead memcg along with its kmem
   caches, which aren't tiny, which might result in noticeable increase
   in memory consumption for no apparent reason in the long run.

 - There are tons of short-lived objects. Accounting them to memcg will
   only result in slight noise and won't change the overall picture, but
   we still have to pay accounting overhead.

For more info, see

 - http://lkml.kernel.org/r/20151105144002.GB15111%40dhcp22.suse.cz
 - http://lkml.kernel.org/r/20151106090555.GK29259@esperanza

Therefore this patchset switches to the white list policy.  Now kmalloc
users have to explicitly opt in by passing __GFP_ACCOUNT flag.

Currently, the list of accounted objects is quite limited and only
includes those allocations that (1) are known to be easily triggered
from userspace and (2) can fail gracefully (for the full list see patch
no.  6) and it still misses many object types.  However, accounting only
those objects should be a satisfactory approximation of the behavior we
used to have for most sane workloads.

This patch (of 6):

Revert 499611ed ("kernfs: do not account ino_ida allocations
to memcg").

Black-list kmem accounting policy (aka __GFP_NOACCOUNT) turned out to be
fragile and difficult to maintain, because there seem to be many more
allocations that should not be accounted than those that should be.
Besides, false accounting an allocation might result in much worse
consequences than not accounting at all, namely increased memory
consumption due to pinned dead kmem caches.

So it was decided to switch to the white-list policy.  This patch reverts
bits introducing the black-list policy.  The white-list policy will be
introduced later in the series.
Signed-off-by: NVladimir Davydov <vdavydov@virtuozzo.com>
Acked-by: NJohannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Greg Thelen <gthelen@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add a new helper function get_first_slab() that get the first slab from
a kmem_cache_node.
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Acked-by: NChristoph Lameter <cl@linux.com>
Acked-by: NDavid Rientjes <rientjes@google.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Simplify the code with list_for_each_entry().
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Acked-by: NChristoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Simplify the code with list_first_entry_or_null().
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Acked-by: NChristoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

A little cleanup - the invocation site provdes the semicolon.

Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

lksb flags are defined both in dlmapi.h and dlmcommon.h.  So clean them
up from dlmcommon.h.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJiufei Xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Found this when do patch review, remove to make it clear and save a
little cpu time.
Signed-off-by: NJunxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_orphan_del, currently it finds and deletes entry first, and
then access orphan dir dinode.  This will have a problem once
ocfs2_journal_access_di fails.  In this case, entry will be removed from
orphan dir, but in deed the inode hasn't been deleted successfully.  In
other words, the file is missing but not actually deleted.  So we should
access orphan dinode first like unlink and rename.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJiufei Xue <xuejiufei@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: NJunxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When two processes are migrating the same lockres,
dlm_add_migration_mle() return -EEXIST, but insert a new mle in hash
list.  dlm_migrate_lockres() will detach the old mle and free the new
one which is already in hash list, that will destroy the list.
Signed-off-by: NJiufei Xue <xuejiufei@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: NJunxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We have found that migration source will trigger a BUG that the refcount
of mle is already zero before put when the target is down during
migration.  The situation is as follows:

dlm_migrate_lockres
  dlm_add_migration_mle
  dlm_mark_lockres_migrating
  dlm_get_mle_inuse
  <<<<<< Now the refcount of the mle is 2.
  dlm_send_one_lockres and wait for the target to become the
  new master.
  <<<<<< o2hb detect the target down and clean the migration
  mle. Now the refcount is 1.

dlm_migrate_lockres woken, and put the mle twice when found the target
goes down which trigger the BUG with the following message:

  "ERROR: bad mle: ".
Signed-off-by: NJiufei Xue <xuejiufei@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

DLM does not cache locks.  So, blocking lock and unlock will only make
the performance worse where contention over the locks is high.
Signed-off-by: NGoldwyn Rodrigues <rgoldwyn@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Reviewed-by: NJunxiao Bi <junxiao.bi@oracle.com>
Cc: Joseph Qi <joseph.qi@huawei.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The following case will lead to slot overwritten.

N1                               N2
mount ocfs2 volume, find and
allocate slot 0, then set
osb->slot_num to 0, begin to
write slot info to disk
                                 mount ocfs2 volume, wait for super lock
write block fail because of
storage link down, unlock
super lock
                                 got super lock and also allocate slot 0
                                 then unlock super lock

mount fail and then dismount,
since osb->slot_num is 0, try to
put invalid slot to disk. And it
will succeed if storage link
restores.
                                 N2 slot info is now overwritten

Once another node say N3 mount, it will find and allocate slot 0 again,
which will lead to mount hung because journal has already been locked by
N2.  so when write slot info failed, invalidate slot in advance to avoid
overwrite slot.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: NYiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

dlm_grab() may return NULL when the node is doing unmount.  When doing
code review, we found that some dlm handlers may return error to caller
when dlm_grab() returns NULL and make caller BUG or other problems.
Here is an example:

Node 1                                 Node 2
receives migration message
from node 3, and send
migrate request to others
                                     start unmounting

                                     receives migrate request
                                     from node 1 and call
                                     dlm_migrate_request_handler()

                                     unmount thread unregisters
                                     domain handlers and removes
                                     dlm_context from dlm_domains

                                     dlm_migrate_request_handlers()
                                     returns -EINVAL to node 1
Exit migration neither clearing the
migration state nor sending
assert master message to node 3 which
cause node 3 hung.
Signed-off-by: NJiufei Xue <xuejiufei@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NYiwen Jiang <jiangyiwen@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Since iput will take care the NULL check itself, NULL check before
calling it is redundant.  So clean them up.
Signed-off-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit f3f85464 ("ocfs2_dlm: Ensure correct ordering of set/clear
refmap bit on lockres") still exists a race which can't ensure the
ordering is exactly correct.

Node1               Node2                    Node3
umount, migrate
lockres to Node2
                    migrate finished,
                    send migrate request
                    to Node3
                                              received migrate request,
                                              create a migration_mle,
                                              respond to Node2.
                    set DLM_LOCK_RES_SETREF_INPROG
                    and send assert master to
                    Node3
                                              delete migration_mle in
                                              assert_master_handler,
                                              Node3 umount without response
                                              dlm_thread purge
                                              this lockres, send drop
                                              deref message to Node2
                    found the flag of
                    DLM_LOCK_RES_SETREF_INPROG
                    is set, dispatch
                    dlm_deref_lockres_worker to
                    clear refmap, but in function of
                    dlm_deref_lockres_worker,
                    only if node in refmap it wait
                    DLM_LOCK_RES_SETREF_INPROG
                    to be cleared. So worker is
                    done successfully

                                              purge lockres, send
                                              assert master response
                                              to Node1, and finish umount
                    set Node3 in refmap, and it
                    won't be cleared forever, thus
                    lead to umount hung

so wait until DLM_LOCK_RES_SETREF_INPROG is cleared in
dlm_deref_lockres_worker.
Signed-off-by: NYiwen Jiang <jiangyiwen@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NJunxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The ocfs2_extent_tree_operations structures are never modified, so
declare them as const.

Done with the help of Coccinelle.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

We found a race between purge and migration when doing code review.
Node A put lockres to purgelist before receiving the migrate message
from node B which is the master.  Node A call dlm_mig_lockres_handler to
handle this message.

dlm_mig_lockres_handler
  dlm_lookup_lockres
  >>>>>> race window, dlm_run_purge_list may run and send
         deref message to master, waiting the response
  spin_lock(&res->spinlock);
  res->state |= DLM_LOCK_RES_MIGRATING;
  spin_unlock(&res->spinlock);
  dlm_mig_lockres_handler returns

  >>>>>> dlm_thread receives the response from master for the deref
  message and triggers the BUG because the lockres has the state
  DLM_LOCK_RES_MIGRATING with the following message:

dlm_purge_lockres:209 ERROR: 6633EB681FA7474A9C280A4E1A836F0F: res
M0000000000000000030c0300000000 in use after deref
Signed-off-by: NJiufei Xue <xuejiufei@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Reviewed-by: NYiwen Jiang <jiangyiwen@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When run multiple xattr test of ocfs2-test on a three-nodes cluster,
mount failed sometimes with the following message.

  o2hb: Unable to stabilize heartbeart on region D18B775E758D4D80837E8CF3D086AD4A (xvdb)

Stabilize heartbeat depends on the timing order to mount ocfs2 from
cluster nodes and how fast the tcp connections are established.  So
increase unsteady interations to leave more time for it.
Signed-off-by: NJunxiao Bi <junxiao.bi@oracle.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some versions of tar assume that files with st_blocks == 0 do not
contain any data and will skip reading them entirely.  See also commit
9206c561 ("ext4: return non-zero st_blocks for inline data").
Signed-off-by: NJohn Haxby <john.haxby@oracle.com>
Reviewed-by: NMark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Acked-by: NGang He <ghe@suse.com>
Reviewed-by: NJunxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In ocfs2_parse_options,

a) it's better to declare variables(small size) outside of while loop;

b) 'option' will be set by match_int, 'option = 0;' makes no sense, if
   match_int failed, it just goto bail and return.
Signed-off-by: NNorton.Zhu <norton.zhu@huawei.com>
Reviewed-by: NJoseph Qi <joseph.qi@huawei.com>
Cc: Gang He <ghe@suse.com>
Cc: Mark Fasheh <mfasheh@suse.de>
Acked-by: NJoel Becker <jlbec@evilplan.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix build errors that happen when CONFIG_LOGFS=y and CONFIG_MTD=m:

  fs/built-in.o: In function `logfs_mount':
  super.c:(.text+0x92a6f): undefined reference to `logfs_get_sb_mtd'
  fs/built-in.o: In function `logfs_get_sb_bdev':
  (.text+0x93530): undefined reference to `logfs_get_sb_mtd'

This patch avoids the error by changing the dependencies of logfs in a
way that we can no longer configure logfs as built-in when the MTD core
is a loadable module, while leaving the dependency to require at least
one of MTD or BLOCK to be enabled.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Michal Marek <mmarek@suse.cz>
Cc: Peter Chen <peter.chen@freescale.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit ac551828 ("modpost: i2c aliases need no trailing wildcard")
removed the wildcard at the end of the I2C module aliases because I2C
devices have no IDs so the aliases are just arbitrary device names.

This is also true for OF modaliases since a compatible string is used to
define a specific IP hardware block.  So the modalias should match a
specific compatible string and not attempt to match a compatible string
whose name matches the beginning of another one.

For example, the following driver module:

  $ modinfo cros_ec_keyb | grep alias
  alias:          platform:cros-ec-keyb
  alias:          of:N*T*Cgoogle,cros-ec-keyb*

will be tried to be loaded for an alias of:N*T*Cgoogle,cros-ec-keyb-v2
but there could be a different driver that supports the device for that
compatible string so it's better to remove the trailing wildcard for OF.

Also, remove the word "always" from the add_wildcard() function comment
since that was carried from the time where a wildcard was always added
at the end of the module alias for all the devices.
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Suggested-by: NBrian Norris <computersforpeace@gmail.com>
Reviewed-by: NSjoerd Simons <sjoerd.simons@collabora.co.uk>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

At the time that this code was originally written, call_srcu didn't
exist, so this thread was required to ensure that we waited for that
SRCU grace period to settle before finally freeing the object.

It does exist now however and we can much more efficiently use call_srcu
to handle this.  That also allows us to potentially use srcu_barrier to
ensure that they are all of the callbacks have run before proceeding.
In order to conserve space, we union the rcu_head with the g_list.

This will be necessary for nfsd which will allocate marks from a
dedicated slabcache.  We have to be able to ensure that all of the
objects are destroyed before destroying the cache.  That's fairly
Signed-off-by: NJeff Layton <jeff.layton@primarydata.com>
Cc: Eric Paris <eparis@parisplace.org>
Reviewed-by: NJan Kara <jack@suse.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

To make the intention clearer, use list_next_entry instead of
list_entry.
Signed-off-by: NGeliang Tang <geliangtang@163.com>
Reviewed-by: NJan Kara <jack@suse.cz>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In Python3+ print is a function so the old syntax is not correct
anymore:

  $ ./scripts/bloat-o-meter vmlinux.o vmlinux.o.old
    File "./scripts/bloat-o-meter", line 61
      print "add/remove: %s/%s grow/shrink: %s/%s up/down: %s/%s (%s)" % \
                                                                     ^
  SyntaxError: invalid syntax

Fix by calling print as a function.

Tested on python 2.7.11, 3.5.1
Signed-off-by: NSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

In include/asm-generic/sections.h:

  /*
   * Usage guidelines:
   * _text, _data: architecture specific, don't use them in
   * arch-independent code
   * [_stext, _etext]: contains .text.* sections, may also contain
   * .rodata.*
   *                   and/or .init.* sections

_text is not guaranteed across architectures.  Architectures such as ARM
may reuse parts which are not actually text and erroneously trigger a bug.
Switch to using _stext which is guaranteed to contain text sections.

Came out of https://lkml.kernel.org/g/<567B1176.4000106@redhat.com>
Signed-off-by: NLaura Abbott <labbott@fedoraproject.org>
Reviewed-by: NKees Cook <keescook@chromium.org>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The build of m32104ut_defconfig for m32r arch was failing for long long
time with the error:

  ERROR: "memory_start" [fs/udf/udf.ko] undefined!
  ERROR: "memory_end" [fs/udf/udf.ko] undefined!
  ERROR: "memory_end" [drivers/scsi/sg.ko] undefined!
  ERROR: "memory_start" [drivers/scsi/sg.ko] undefined!
  ERROR: "memory_end" [drivers/i2c/i2c-dev.ko] undefined!
  ERROR: "memory_start" [drivers/i2c/i2c-dev.ko] undefined!

As done in other architectures export the symbols to fix the error.
Reported-by: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NSudip Mukherjee <sudip@vectorindia.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Pull xfs updates from Dave Chinner:
 "There's not a lot in this - the main addition is the CRC validation of
  the entire region of the log that the will be recovered, along with
  several log recovery fixes.  Most of the rest is small bug fixes and
  cleanups.

  I have three bug fixes still pending, all that address recently fixed
  regressions that I will send to next week after they've had some time
  in for-next.

  Summary:
   - extensive CRC validation during log recovery
   - several log recovery bug fixes
   - Various DAX support fixes
   - AGFL size calculation fix
   - various cleanups in preparation for new functionality
   - project quota ENOSPC notification via netlink
   - tracing and debug improvements"

* tag 'xfs-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/dgc/linux-xfs: (26 commits)
  xfs: handle dquot buffer readahead in log recovery correctly
  xfs: inode recovery readahead can race with inode buffer creation
  xfs: eliminate committed arg from xfs_bmap_finish
  xfs: bmapbt checking on debug kernels too expensive
  xfs: add tracepoints to readpage calls
  xfs: debug mode log record crc error injection
  xfs: detect and trim torn writes during log recovery
  xfs: fix recursive splice read locking with DAX
  xfs: Don't use reserved blocks for data blocks with DAX
  XFS: Use a signed return type for suffix_kstrtoint()
  libxfs: refactor short btree block verification
  libxfs: pack the agfl header structure so XFS_AGFL_SIZE is correct
  libxfs: use a convenience variable instead of open-coding the fork
  xfs: fix log ticket type printing
  libxfs: make xfs_alloc_fix_freelist non-static
  xfs: make xfs_buf_ioend_async() static
  xfs: send warning of project quota to userspace via netlink
  xfs: get mp from bma->ip in xfs_bmap code
  xfs: print name of verifier if it fails
  libxfs: Optimize the loop for xfs_bitmap_empty
  ...

Pull f2fs updates from Jaegeuk Kim:
 "This series adds two ioctls to control cached data and fragmented
  files.  Most of the rest fixes missing error cases and bugs that we
  have not covered so far.  Summary:

  Enhancements:
   - support an ioctl to execute online file defragmentation
   - support an ioctl to flush cached data
   - speed up shrinking of extent_cache entries
   - handle broken superblock
   - refector dirty inode management infra
   - revisit f2fs_map_blocks to handle more cases
   - reduce global lock coverage
   - add detecting user's idle time

  Major bug fixes:
   - fix data race condition on cached nat entries
   - fix error cases of volatile and atomic writes"

* tag 'for-f2fs-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (87 commits)
  f2fs: should unset atomic flag after successful commit
  f2fs: fix wrong memory condition check
  f2fs: monitor the number of background checkpoint
  f2fs: detect idle time depending on user behavior
  f2fs: introduce time and interval facility
  f2fs: skip releasing nodes in chindless extent tree
  f2fs: use atomic type for node count in extent tree
  f2fs: recognize encrypted data in f2fs_fiemap
  f2fs: clean up f2fs_balance_fs
  f2fs: remove redundant calls
  f2fs: avoid unnecessary f2fs_balance_fs calls
  f2fs: check the page status filled from disk
  f2fs: introduce __get_node_page to reuse common code
  f2fs: check node id earily when readaheading node page
  f2fs: read isize while holding i_mutex in fiemap
  Revert "f2fs: check the node block address of newly allocated nid"
  f2fs: cover more area with nat_tree_lock
  f2fs: introduce max_file_blocks in sbi
  f2fs crypto: check CONFIG_F2FS_FS_XATTR for encrypted symlink
  f2fs: introduce zombie list for fast shrinking extent trees
  ...

Pull first round of SCSI updates from James Bottomley:
 "This includes driver updates from the usual suspects (bfa, arcmsr,
  scsi_dh_alua, lpfc, storvsc, cxlflash).

  The major change is the addition of the hisi_sas driver, which is an
  ARM platform device for SAS.  The other change of note is an enormous
  style transformation to the atp870u driver (which is our worst written
  SCSI driver)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (169 commits)
  cxlflash: Enable device id for future IBM CXL adapter
  cxlflash: Resolve oops in wait_port_offline
  cxlflash: Fix to resolve cmd leak after host reset
  cxlflash: Removed driver date print
  cxlflash: Fix to avoid virtual LUN failover failure
  cxlflash: Fix to escalate LINK_RESET also on port 1
  storvsc: Tighten up the interrupt path
  storvsc: Refactor the code in storvsc_channel_init()
  storvsc: Properly support Fibre Channel devices
  storvsc: Fix a bug in the layout of the hv_fc_wwn_packet
  mvsas: Add SGPIO support to Marvell 94xx
  mpt3sas: A correction in unmap_resources
  hpsa: Add box and bay information for enclosure devices
  hpsa: Change SAS transport devices to bus 0.
  hpsa: fix path_info_show
  cciss: print max outstanding commands as a hex value
  scsi_debug: Increase the reported optimal transfer length
  lpfc: Update version to 11.0.0.10 for upstream patch set
  lpfc: Use kzalloc instead of kmalloc
  lpfc: Delete unnecessary checks before the function call "mempool_destroy"
  ...

Pull libnvdimm updates from Dan Williams:
 "The bulk of this has appeared in -next and independently received a
  build success notification from the kbuild robot.  The 'for-4.5/block-
  dax' topic branch was rebased over the weekend to drop the "block
  device end-of-life" rework that Al would like to see re-implemented
  with a notifier, and to address bug reports against the badblocks
  integration.

  There is pending feedback against "libnvdimm: Add a poison list and
  export badblocks" received last week.  Linda identified some localized
  fixups that we will handle incrementally.

  Summary:

   - Media error handling: The 'badblocks' implementation that
     originated in md-raid is up-levelled to a generic capability of a
     block device.  This initial implementation is limited to being
     consulted in the pmem block-i/o path.  Later, 'badblocks' will be
     consulted when creating dax mappings.

   - Raw block device dax: For virtualization and other cases that want
     large contiguous mappings of persistent memory, add the capability
     to dax-mmap a block device directly.

   - Increased /dev/mem restrictions: Add an option to treat all
     io-memory as IORESOURCE_EXCLUSIVE, i.e. disable /dev/mem access
     while a driver is actively using an address range.  This behavior
     is controlled via the new CONFIG_IO_STRICT_DEVMEM option and can be
     overridden by the existing "iomem=relaxed" kernel command line
     option.

   - Miscellaneous fixes include a 'pfn'-device huge page alignment fix,
     block device shutdown crash fix, and other small libnvdimm fixes"

* tag 'libnvdimm-for-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (32 commits)
  block: kill disk_{check|set|clear|alloc}_badblocks
  libnvdimm, pmem: nvdimm_read_bytes() badblocks support
  pmem, dax: disable dax in the presence of bad blocks
  pmem: fail io-requests to known bad blocks
  libnvdimm: convert to statically allocated badblocks
  libnvdimm: don't fail init for full badblocks list
  block, badblocks: introduce devm_init_badblocks
  block: clarify badblocks lifetime
  badblocks: rename badblocks_free to badblocks_exit
  libnvdimm, pmem: move definition of nvdimm_namespace_add_poison to nd.h
  libnvdimm: Add a poison list and export badblocks
  nfit_test: Enable DSMs for all test NFITs
  md: convert to use the generic badblocks code
  block: Add badblock management for gendisks
  badblocks: Add core badblock management code
  block: fix del_gendisk() vs blkdev_ioctl crash
  block: enable dax for raw block devices
  block: introduce bdev_file_inode()
  restrict /dev/mem to idle io memory ranges
  arch: consolidate CONFIG_STRICT_DEVM in lib/Kconfig.debug
  ...

Pull s390 updates from Martin Schwidefsky:
 "Among the traditional bug fixes and cleanups are some improvements:

   - A tool to generated the facility lists, generating the bit fields
     by hand has been a source of bugs in the past

   - The spinlock loop is reordered to avoid bursts of hypervisor calls

   - Add support for the open-for-business interface to the service
     element

   - The get_cpu call is added to the vdso

   - A set of tracepoints is defined for the common I/O layer

   - The deprecated sclp_cpi module is removed

   - Update default configuration"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (56 commits)
  s390/sclp: fix possible control register corruption
  s390: fix normalization bug in exception table sorting
  s390/configs: update default configurations
  s390/vdso: optimize getcpu system call
  s390: drop smp_mb in vdso_init
  s390: rename struct _lowcore to struct lowcore
  s390/mem_detect: use unsigned longs
  s390/ptrace: get rid of long longs in psw_bits
  s390/sysinfo: add missing SYSIB 1.2.2 multithreading fields
  s390: get rid of CONFIG_SCHED_MC and CONFIG_SCHED_BOOK
  s390/Kconfig: remove pointless 64 bit dependencies
  s390/dasd: fix failfast for disconnected devices
  s390/con3270: testing return kzalloc retval
  s390/hmcdrv: constify hmcdrv_ftp_ops structs
  s390/cio: add NULL test
  s390/cio: Change I/O instructions from inline to normal functions
  s390/cio: Introduce common I/O layer tracepoints
  s390/cio: Consolidate inline assemblies and related data definitions
  s390/cio: Fix incorrect xsch opcode specification
  s390/cio: Remove unused inline assemblies
  ...

Pull ia64 build fixes from Tony Luck:
 "The ARM guys broke the ia64 build ...  but gave me fixes, so it's all
  good now"

* tag 'please-pull-fixefi' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux:
  efi: include asm/early_ioremap.h not asm/efi.h to get early_memremap
  ia64: split off early_ioremap() declarations into asm/early_ioremap.h

Pull second batch of media updates from Mauro Carvalho Chehab:
 "This is the second part of the media patches.  It contains the media
  controller next generation patches, with is the result of one year of
  discussions and development.  It also contains patches to enable media
  controller support at the DVB subsystem.

  The goal is to improve the media controller to allow proper support
  for other types of Video4Linux devices (radio and TV ones) and to
  extend the media controller functionality to allow it to be used by
  other subsystems like DVB, ALSA and IIO.

  In order to use the new functionality, a new ioctl is needed
  (MEDIA_IOC_G_TOPOLOGY).  As we're still discussing how to pack the
  struct fields of this ioctl in order to avoid compat32 issues, I
  decided to add a patch at the end of this series commenting out the
  new ioctl, in order to postpone the addition of the new ioctl to the
  next Kernel version (4.6).

  With that, no userspace visible changes should happen at the media
  controller API, as the existing ioctls are untouched.  Yet, it helps
  DVB, ALSA and IIO developers to develop and test the patches adding
  media controller support there, as the core will contain all required
  internal changes to allow adding support for devices that belong to
  those subsystems"

* tag 'media/v4.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (177 commits)
  [media] Postpone the addition of MEDIA_IOC_G_TOPOLOGY
  [media] mxl111sf: Add a tuner entity
  [media] dvbdev: create links on devices with multiple frontends
  [media] media-entitiy: add a function to create multiple links
  [media] dvb-usb-v2: postpone removal of media_device
  [media] dvbdev: Add RF connector if needed
  [media] dvbdev: remove two dead functions if !CONFIG_MEDIA_CONTROLLER_DVB
  [media] call media_device_init() before registering the V4L2 device
  [media] uapi/media.h: Use u32 for the number of graph objects
  [media] media-entity: don't sleep at media_device_register_entity()
  [media] media-entity: increase max number of PADs
  [media] media-entity.h: document the remaining functions
  [media] media-device.h: use just one u32 counter for object ID
  [media] media-entity.h fix documentation for several parameters
  [media] DocBook: document media_entity_graph_walk_cleanup()
  [media] move documentation to the header files
  [media] media: Move MEDIA_ENTITY_MAX_PADS from media-entity.h to media-entity.c
  [media] media: Remove pre-allocated entity enumeration bitmap
  [media] staging: v4l: davinci_vpbe: Use the new media graph walk interface
  [media] staging: v4l: omap4iss: Use the new media graph walk interface
  ...

Pull spi updates from Mark Brown:
 "A quiet release for SPI, not even many driver updates:

   - Add a dummy loopback driver for use in exercising framework
     features during development.

   - Move the test utilities to tools/ and add support for transferring
     data to and from a file instead of stdin and stdout to spidev_test.

   - Support for Mediatek MT2701 and Renesas AG5 deices"

* tag 'spi-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi: (69 commits)
  spi: loopback: fix typo in MODULE_PARM_DESC
  spi: sun4i: Prevent chip-select from being activated twice before a transfer
  spi: loopback-test: spi_check_rx_ranges can get always done
  spi: loopback-test: rename method spi_test_fill_tx to spi_test_fill_pattern
  spi: loopback-test: write rx pattern also when running without tx_buf
  spi: fsl-espi: expose maximum transfer size limit
  spi: expose master transfer size limitation.
  spi: zynq: use to_platform_device()
  spi: cadence: use to_platform_device()
  spi: mediatek: Add spi support for mt2701 IC
  spi: mediatek: merge all identical compat to mtk_common_compat
  spi: mtk: Add bindings for mediatek MT2701 soc platform
  spi: mediatek: Prevent overflows in FIFO transfers
  spi: s3c64xx: Remove unused platform_device_id entries
  spi: use to_spi_device
  spi: dw: Use SPI_TMOD_TR rather than magic const 0 to set tmode
  spi: imx: defer spi initialization, if DMA engine is
  spi: imx: return error from dma channel request
  spi: imx: enable loopback only for ECSPI controller family
  spi: imx: fix loopback mode setup after controller reset
  ...

Pull MTD updates from Brian Norris:
 "Generic MTD:

   - populate the MTD device 'of_node' field (and get a proper 'of_node'
     symlink in sysfs)

     This yielded some new helper functions, and changes across a
     variety of drivers

   - partitioning cleanups, to prepare for better device-tree based
     partitioning in the future

     Eliminate a lot of boilerplate for drivers that want to use
     OF-based partition parsing

     The DT bindings for this didn't settle yet, so most non-cleanup
     portions are deferred for a future release

  NAND:

   - embed a struct mtd_info inside struct nand_chip

     This is really long overdue; too many drivers have to do the same
     silly boilerplate to allocate and link up two "independent"
     structs, when in fact, everyone is assuming there is an exact 1:1
     relationship between a NAND chips struct and its underlying MTD.
     This aids improved helpers and should make certain abstractions
     easier in the future.

     Also causes a lot of churn, helped along by some automated code
     transformations

   - add more core support for detecting (and "correcting") bitflips in
     erased pages; requires opt-in by drivers, but at least we kill a
     few bad implementations and hopefully stave off future ones

   - pxa3xx_nand: cleanups, a few fixes, and PM improvements

   - new JZ4780 NAND driver

  SPI NOR:

   - provide default erase function, for controllers that just want to
     send the SECTOR_ERASE command directly

   - fix some module auto-loading issues with device tree
     ("jedec,spi-nor")

   - error handling fixes

   - new Mediatek QSPI flash driver

  Other:

   - cfi: force valid geometry Kconfig (finally!)

     This one used to trip up randconfigs occasionally, since bots
     aren't deterred by big scary "advanced configuration" menus

  More? Probably. See the commit logs"

* tag 'for-linus-20160112' of git://git.infradead.org/linux-mtd: (168 commits)
  mtd: jz4780_nand: replace if/else blocks with switch/case
  mtd: nand: jz4780: Update ecc correction error codes
  mtd: nandsim: use nand_get_controller_data()
  mtd: jz4780_nand: remove useless mtd->priv = chip assignment
  staging: mt29f_spinand: make use of nand_set/get_controller_data() helpers
  mtd: nand: make use of nand_set/get_controller_data() helpers
  ARM: make use of nand_set/get_controller_data() helpers
  mtd: nand: add helpers to access ->priv
  mtd: nand: jz4780: driver for NAND devices on JZ4780 SoCs
  mtd: nand: jz4740: remove custom 'erased check' implementation
  mtd: nand: diskonchip: remove custom 'erased check' implementation
  mtd: nand: davinci: remove custom 'erased check' implementation
  mtd: nand: use nand_check_erased_ecc_chunk in default ECC read functions
  mtd: nand: return consistent error codes in ecc.correct() implementations
  doc: dt: mtd: new binding for jz4780-{nand,bch}
  mtd: cfi_cmdset_0001: fixing memory leak and handling failed kmalloc
  mtd: spi-nor: wait until lock/unlock operations are ready
  mtd: tests: consolidate kmalloc/memset 0 call to kzalloc
  jffs2: use to_delayed_work
  mtd: nand: assign reasonable default name for NAND drivers
  ...

Pull ipmi updates from Corey Minyard:
 "Some minor changes that have been in linux-next for a while"

* tag 'for-linus-4.5' of git://git.code.sf.net/p/openipmi/linux-ipmi:
  ipmi: Remove unnecessary pci_disable_device.
  char: ipmi: Drop owner assignment from i2c_driver
  ipmi: constify some struct and char arrays

Pull input updates from Dmitry Torokhov:
 - new driver for eGalaxTouch serial touchscreen
 - new driver for TS-4800 touchscreen
 - an update for Goodix touchscreen driver
 - PS/2 mouse module was reworked to limit number of protocols we try on
   pass-through ports to speed up their detection time
 - wacom_w8001 touchscreen driver now reports pen and touch via separate
   instances of input devices
 - other driver changes

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (42 commits)
  Input: elantech - mark protocols v2 and v3 as semi-mt
  Input: wacom_w8001 - drop use of ABS_MT_TOOL_TYPE
  Input: gpio-keys - fix check for disabling unsupported keys
  Input: omap-keypad - remove dead check
  Input: ti_am335x_tsc - fix HWPEN interrupt handling
  Input: omap-keypad - set tasklet data earlier
  Input: rohm_bu21023 - fix handling of retrying firmware update
  Input: ALPS - report v3 pinnacle trackstick device only if is present
  Input: ALPS - detect trackstick presence for v7 protocol
  Input: pcap_ts - use to_delayed_work
  Input: bma150 - constify bma150_cfg structure
  Input: i8042 - add Fujitsu Lifebook U745 to the nomux list
  Input: egalax_ts_serial - fix potential NULL dereference on error
  Input: uinput - sanity check on ff_effects_max and EV_FF
  Input: uinput - rework ABS validation
  Input: uinput - add new UINPUT_DEV_SETUP and UI_ABS_SETUP ioctl
  Input: goodix - use "inverted_[xy]" flags instead of "rotated_screen"
  Input: goodix - add axis swapping and axis inversion support
  Input: goodix - use goodix_i2c_write_u8 instead of i2c_master_send
  Input: goodix - add power management support
  ...