4072 Commits

Author SHA1 Message Date
Johannes Weiner
f4b109c6da lib: radix-tree: add entry deletion support to __radix_tree_replace()
Page cache shadow entry handling will be a lot simpler when it can use a
single generic replacement function for pages, shadow entries, and
emptying slots.

Make __radix_tree_replace() properly account insertions and deletions in
node->count and garbage collect nodes as they become empty.  Then
re-implement radix_tree_delete() on top of it.

Link: http://lkml.kernel.org/r/20161117193058.GC23430@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Johannes Weiner
6d75f366b9 lib: radix-tree: check accounting of existing slot replacement users
The bug in khugepaged fixed earlier in this series shows that radix tree
slot replacement is fragile; and it will become more so when not only
NULL<->!NULL transitions need to be caught but transitions from and to
exceptional entries as well.  We need checks.

Re-implement radix_tree_replace_slot() on top of the sanity-checked
__radix_tree_replace().  This requires existing callers to also pass the
radix tree root, but it'll warn us when somebody replaces slots with
contents that need proper accounting (transitions between NULL entries,
real entries, exceptional entries) and where a replacement through the
slot pointer would corrupt the radix tree node counts.

Link: http://lkml.kernel.org/r/20161117193021.GB23430@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Suggested-by: Jan Kara <jack@suse.cz>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Johannes Weiner
f7942430e4 lib: radix-tree: native accounting of exceptional entries
The way the page cache is sneaking shadow entries of evicted pages into
the radix tree past the node entry accounting and tracking them manually
in the upper bits of node->count is fraught with problems.

These shadow entries are marked in the tree as exceptional entries,
which are a native concept to the radix tree.  Maintain an explicit
counter of exceptional entries in the radix tree node.  Subsequent
patches will switch shadow entry tracking over to that counter.

DAX and shmem are the other users of exceptional entries.  Since slot
replacements that change the entry type from regular to exceptional must
now be accounted, introduce a __radix_tree_replace() function that does
replacement and accounting, and switch DAX and shmem over.

The increase in radix tree node size is temporary.  A followup patch
switches the shadow tracking to this new scheme and we'll no longer need
the upper bits in node->count and shrink that back to one byte.

Link: http://lkml.kernel.org/r/20161117192945.GA23430@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <mawilcox@linuxonhyperv.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-12 18:55:08 -08:00
Linus Torvalds
6cdf89b1ca Merge branch 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
 "The tree got pretty big in this development cycle, but the net effect
  is pretty good:

    115 files changed, 673 insertions(+), 1522 deletions(-)

  The main changes were:

   - Rework and generalize the mutex code to remove per arch mutex
     primitives. (Peter Zijlstra)

   - Add vCPU preemption support: add an interface to query the
     preemption status of vCPUs and use it in locking primitives - this
     optimizes paravirt performance. (Pan Xinhui, Juergen Gross,
     Christian Borntraeger)

   - Introduce cpu_relax_yield() and remov cpu_relax_lowlatency() to
     clean up and improve the s390 lock yielding machinery and its core
     kernel impact. (Christian Borntraeger)

   - Micro-optimize mutexes some more. (Waiman Long)

   - Reluctantly add the to-be-deprecated mutex_trylock_recursive()
     interface on a temporary basis, to give the DRM code more time to
     get rid of its locking hacks. Any other users will be NAK-ed on
     sight. (We turned off the deprecation warning for the time being to
     not pollute the build log.) (Peter Zijlstra)

   - Improve the rtmutex code a bit, in light of recent long lived
     bugs/races. (Thomas Gleixner)

   - Misc fixes, cleanups"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  x86/paravirt: Fix bool return type for PVOP_CALL()
  x86/paravirt: Fix native_patch()
  locking/ww_mutex: Use relaxed atomics
  locking/rtmutex: Explain locking rules for rt_mutex_proxy_unlock()/init_proxy_locked()
  locking/rtmutex: Get rid of RT_MUTEX_OWNER_MASKALL
  x86/paravirt: Optimize native pv_lock_ops.vcpu_is_preempted()
  locking/mutex: Break out of expensive busy-loop on {mutex,rwsem}_spin_on_owner() when owner vCPU is preempted
  locking/osq: Break out of spin-wait busy waiting loop for a preempted vCPU in osq_lock()
  Documentation/virtual/kvm: Support the vCPU preemption check
  x86/xen: Support the vCPU preemption check
  x86/kvm: Support the vCPU preemption check
  x86/kvm: Support the vCPU preemption check
  kvm: Introduce kvm_write_guest_offset_cached()
  locking/core, x86/paravirt: Implement vcpu_is_preempted(cpu) for KVM and Xen guests
  locking/spinlocks, s390: Implement vcpu_is_preempted(cpu)
  locking/core, powerpc: Implement vcpu_is_preempted(cpu)
  sched/core: Introduce the vcpu_is_preempted(cpu) interface
  sched/wake_q: Rename WAKE_Q to DEFINE_WAKE_Q
  locking/core: Provide common cpu_relax_yield() definition
  locking/mutex: Don't mark mutex_trylock_recursive() as deprecated, temporarily
  ...
2016-12-12 10:48:02 -08:00
Linus Torvalds
718c0ddd6a Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this development cycle were:

   - Miscellaneous fixes, including a change to call_rcu()'s rcu_head
     alignment check.

   - Security-motivated list consistency checks, which are disabled by
     default behind DEBUG_LIST.

   - Torture-test updates.

   - Documentation updates, yet again just simple changes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  torture: Prevent jitter from delaying build-only runs
  torture: Remove obsolete files from rcutorture .gitignore
  rcu: Don't kick unless grace period or request
  rcu: Make expedited grace periods recheck dyntick idle state
  torture: Trace long read-side delays
  rcu: RCU_TRACE enables event tracing as well as debugfs
  rcu: Remove obsolete comment from __call_rcu()
  rcu: Remove obsolete rcu_check_callbacks() header comment
  rcu: Tighten up __call_rcu() rcu_head alignment check
  Documentation/RCU: Fix minor typo
  documentation: Present updated RCU guarantee
  bug: Avoid Kconfig warning for BUG_ON_DATA_CORRUPTION
  lib/Kconfig.debug: Fix typo in select statement
  lkdtm: Add tests for struct list corruption
  bug: Provide toggle for BUG on data corruption
  list: Split list_del() debug checking into separate function
  rculist: Consolidate DEBUG_LIST for list_add_rcu()
  list: Split list_add() debug checking into separate function
2016-12-12 09:09:54 -08:00
Ingo Molnar
6f38751510 Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:07:13 +01:00
David S. Miller
821781a9f4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-12-10 16:21:55 -05:00
Linus Torvalds
2b41226b39 Revert "radix tree test suite: fix compilation"
This reverts commit 53855d10f4567a0577360b6448d52a863929775b.

It shouldn't have come in yet - it depends on the changes in linux-next
that will come in during the next merge window.  As Matthew Wilcox says,
the test suite is broken with the current state without the revert.

Requested-by: Matthew Wilcox <mawilcox@microsoft.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-09 10:41:42 -08:00
Matthew Wilcox
53855d10f4 radix tree test suite: fix compilation
Patch "lib/radix-tree: Convert to hotplug state machine" breaks the test
suite as it adds a call to cpuhp_setup_state_nocalls() which is not
currently emulated in the test suite.  Add it, and delete the emulation
of the old CPU hotplug mechanism.

Link: http://lkml.kernel.org/r/1480369871-5271-36-git-send-email-mawilcox@linuxonhyperv.com
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Tested-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-12-07 17:10:00 -08:00
Linus Torvalds
5b43f97f3f Merge branch 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Ingo Molnar:
 "Two rtmutex race fixes (which miraculously never triggered, that we
  know of), plus two lockdep printk formatting regression fixes"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  lockdep: Fix report formatting
  locking/rtmutex: Use READ_ONCE() in rt_mutex_owner()
  locking/rtmutex: Prevent dequeue vs. unlock race
  locking/selftest: Fix output since KERN_CONT changes
2016-12-07 11:27:33 -08:00
James Smart
a317178e36 parser: add u64 number parser
Will be used by the nvme-fabrics FC transport in parsing options

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2016-12-06 10:17:03 +02:00
Al Viro
cbbd26b8b1 [iov_iter] new primitives - copy_from_iter_full() and friends
copy_from_iter_full(), copy_from_iter_full_nocache() and
csum_and_copy_from_iter_full() - counterparts of copy_from_iter()
et.al., advancing iterator only in case of successful full copy
and returning whether it had been successful or not.

Convert some obvious users.  *NOTE* - do not blindly assume that
something is a good candidate for those unless you are sure that
not advancing iov_iter in failure case is the right thing in
this case.  Anything that does short read/short write kind of
stuff (or is in a loop, etc.) is unlikely to be a good one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-12-05 14:33:36 -05:00
David S. Miller
2745529ac7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Couple conflicts resolved here:

1) In the MACB driver, a bug fix to properly initialize the
   RX tail pointer properly overlapped with some changes
   to support variable sized rings.

2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix
   overlapping with a reorganization of the driver to support
   ACPI, OF, as well as PCI variants of the chip.

3) In 'net' we had several probe error path bug fixes to the
   stmmac driver, meanwhile a lot of this code was cleaned up
   and reorganized in 'net-next'.

4) The cls_flower classifier obtained a helper function in
   'net-next' called __fl_delete() and this overlapped with
   Daniel Borkamann's bug fix to use RCU for object destruction
   in 'net'.  It also overlapped with Jiri's change to guard
   the rhashtable_remove_fast() call with a check against
   tc_skip_sw().

5) In mlx4, a revert bug fix in 'net' overlapped with some
   unrelated changes in 'net-next'.

6) In geneve, a stale header pointer after pskb_expand_head()
   bug fix in 'net' overlapped with a large reorganization of
   the same code in 'net-next'.  Since the 'net-next' code no
   longer had the bug in question, there was nothing to do
   other than to simply take the 'net-next' hunks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 12:29:53 -05:00
Ingo Molnar
1b95b1a06c Merge branch 'locking/urgent' into locking/core, to pick up dependent fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-02 11:13:44 +01:00
Dmitry Vyukov
828347f8f9 kasan: support use-after-scope detection
Gcc revision 241896 implements use-after-scope detection.  Will be
available in gcc 7.  Support it in KASAN.

Gcc emits 2 new callbacks to poison/unpoison large stack objects when
they go in/out of scope.  Implement the callbacks and add a test.

[dvyukov@google.com: v3]
  Link: http://lkml.kernel.org/r/1479998292-144502-1-git-send-email-dvyukov@google.com
Link: http://lkml.kernel.org/r/1479226045-145148-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: <stable@vger.kernel.org>	[4.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-30 16:32:52 -08:00
Chris Wilson
f8ff04e2be lib/debugobjects: export for use in modules
Drivers, or other modules, that use a mixture of objects (especially
objects embedded within other objects) would like to take advantage of
the debugobjects facilities to help catch misuse.  Currently, the
debugobjects interface is only available to builtin drivers and requires
a set of EXPORT_SYMBOL_GPL for use by modules.

I am using the debugobjects in i915.ko to try and catch some invalid
operations on embedded objects.  The problem currently only presents
itself across module unload so forcing i915 to be builtin is not an
option.

Link: http://lkml.kernel.org/r/20161122143039.6433-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: "Du, Changbin" <changbin.du@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-30 16:32:52 -08:00
David S. Miller
0b42f25d2f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
udplite conflict is resolved by taking what 'net-next' did
which removed the backlog receive method assignment, since
it is no longer necessary.

Two entries were added to the non-priv ethtool operations
switch statement, one in 'net' and one in 'net-next, so
simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-26 23:42:21 -05:00
Michael Ellerman
2513940989 locking/selftest: Fix output since KERN_CONT changes
Since the KERN_CONT changes the locking-selftest output is messed up, eg:

  ----------------------------------------------------------------------------
                                   | spin |wlock |rlock |mutex | wsem | rsem |
    --------------------------------------------------------------------------
                       A-A deadlock:
    ok  |
    ok  |
    ok  |
    ok  |
    ok  |
    ok  |

Use pr_cont() to get it looking normal again:

  ----------------------------------------------------------------------------
                                   | spin |wlock |rlock |mutex | wsem | rsem |
    --------------------------------------------------------------------------
                       A-A deadlock:  ok  |  ok  |  ok  |  ok  |  ok  |  ok  |

Reported-by: Christian Kujau <lists@nerdbynature.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@ozlabs.org
Link: http://lkml.kernel.org/r/1480027528-934-1-git-send-email-mpe@ellerman.id.au
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-25 07:12:19 +01:00
Andrey Ryabinin
f5527fffff mpi: Fix NULL ptr dereference in mpi_powm() [ver #3]
This fixes CVE-2016-8650.

If mpi_powm() is given a zero exponent, it wants to immediately return
either 1 or 0, depending on the modulus.  However, if the result was
initalised with zero limb space, no limbs space is allocated and a
NULL-pointer exception ensues.

Fix this by allocating a minimal amount of limb space for the result when
the 0-exponent case when the result is 1 and not touching the limb space
when the result is 0.

This affects the use of RSA keys and X.509 certificates that carry them.

BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6
PGD 0
Oops: 0002 [#1] SMP
Modules linked in:
CPU: 3 PID: 3014 Comm: keyctl Not tainted 4.9.0-rc6-fscache+ #278
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
task: ffff8804011944c0 task.stack: ffff880401294000
RIP: 0010:[<ffffffff8138ce5d>]  [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6
RSP: 0018:ffff880401297ad8  EFLAGS: 00010212
RAX: 0000000000000000 RBX: ffff88040868bec0 RCX: ffff88040868bba0
RDX: ffff88040868b260 RSI: ffff88040868bec0 RDI: ffff88040868bee0
RBP: ffff880401297ba8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000047 R11: ffffffff8183b210 R12: 0000000000000000
R13: ffff8804087c7600 R14: 000000000000001f R15: ffff880401297c50
FS:  00007f7a7918c700(0000) GS:ffff88041fb80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 0000000401250000 CR4: 00000000001406e0
Stack:
 ffff88040868bec0 0000000000000020 ffff880401297b00 ffffffff81376cd4
 0000000000000100 ffff880401297b10 ffffffff81376d12 ffff880401297b30
 ffffffff81376f37 0000000000000100 0000000000000000 ffff880401297ba8
Call Trace:
 [<ffffffff81376cd4>] ? __sg_page_iter_next+0x43/0x66
 [<ffffffff81376d12>] ? sg_miter_get_next_page+0x1b/0x5d
 [<ffffffff81376f37>] ? sg_miter_next+0x17/0xbd
 [<ffffffff8138ba3a>] ? mpi_read_raw_from_sgl+0xf2/0x146
 [<ffffffff8132a95c>] rsa_verify+0x9d/0xee
 [<ffffffff8132acca>] ? pkcs1pad_sg_set_buf+0x2e/0xbb
 [<ffffffff8132af40>] pkcs1pad_verify+0xc0/0xe1
 [<ffffffff8133cb5e>] public_key_verify_signature+0x1b0/0x228
 [<ffffffff8133d974>] x509_check_for_self_signed+0xa1/0xc4
 [<ffffffff8133cdde>] x509_cert_parse+0x167/0x1a1
 [<ffffffff8133d609>] x509_key_preparse+0x21/0x1a1
 [<ffffffff8133c3d7>] asymmetric_key_preparse+0x34/0x61
 [<ffffffff812fc9f3>] key_create_or_update+0x145/0x399
 [<ffffffff812fe227>] SyS_add_key+0x154/0x19e
 [<ffffffff81001c2b>] do_syscall_64+0x80/0x191
 [<ffffffff816825e4>] entry_SYSCALL64_slow_path+0x25/0x25
Code: 56 41 55 41 54 53 48 81 ec a8 00 00 00 44 8b 71 04 8b 42 04 4c 8b 67 18 45 85 f6 89 45 80 0f 84 b4 06 00 00 85 c0 75 2f 41 ff ce <49> c7 04 24 01 00 00 00 b0 01 75 0b 48 8b 41 18 48 83 38 01 0f
RIP  [<ffffffff8138ce5d>] mpi_powm+0x32/0x7e6
 RSP <ffff880401297ad8>
CR2: 0000000000000000
---[ end trace d82015255d4a5d8d ]---

Basically, this is a backport of a libgcrypt patch:

	http://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git;a=patch;h=6e1adb05d290aeeb1c230c763970695f4a538526

Fixes: cdec9cb5167a ("crypto: GnuPG based MPI lib - source files (part 1)")
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
cc: linux-ima-devel@lists.sourceforge.net
cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.l.morris@oracle.com>
2016-11-25 12:57:50 +11:00
Ingo Molnar
af91a81131 Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu
Pull RCU updates from Paul E. McKenney:

 - Documentation updates, yet again just simple changes.

 - Miscellaneous fixes, including a change to call_rcu()'s
   rcu_head alignment check.

 - Security-motivated list consistency checks, which are
   disabled by default behind DEBUG_LIST.

 - Torture-test updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-23 10:04:28 +01:00
David S. Miller
f9aa9dc7d2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All conflicts were simple overlapping changes except perhaps
for the Thunder driver.

That driver has a change_mtu method explicitly for sending
a message to the hardware.  If that fails it returns an
error.

Normally a driver doesn't need an ndo_change_mtu method becuase those
are usually just range changes, which are now handled generically.
But since this extra operation is needed in the Thunder driver, it has
to stay.

However, if the message send fails we have to restore the original
MTU before the change because the entire call chain expects that if
an error is thrown by ndo_change_mtu then the MTU did not change.
Therefore code is added to nicvf_change_mtu to remember the original
MTU, and to restore it upon nicvf_update_hw_max_frs() failue.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-22 13:27:16 -05:00
Ingo Molnar
02cb689b2c Merge branch 'linus' into locking/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-22 12:37:38 +01:00
Linus Torvalds
8d1a2408ef Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
Pull sparc fixes from David Miller:

 1) With modern networking cards we can run out of 32-bit DMA space, so
    support 64-bit DMA addressing when possible on sparc64. From Dave
    Tushar.

 2) Some signal frame validation checks are inverted on sparc32, fix
    from Andreas Larsson.

 3) Lockdep tables can get too large in some circumstances on sparc64,
    add a way to adjust the size a bit. From Babu Moger.

 4) Fix NUMA node probing on some sun4v systems, from Thomas Tai.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc: drop duplicate header scatterlist.h
  lockdep: Limit static allocations if PROVE_LOCKING_SMALL is defined
  config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc
  sunbmac: Fix compiler warning
  sunqe: Fix compiler warnings
  sparc64: Enable 64-bit DMA
  sparc64: Enable sun4v dma ops to use IOMMU v2 APIs
  sparc64: Bind PCIe devices to use IOMMU v2 service
  sparc64: Initialize iommu_map_table and iommu_pool
  sparc64: Add ATU (new IOMMU) support
  sparc64: Add FORCE_MAX_ZONEORDER and default to 13
  sparc64: fix compile warning section mismatch in find_node()
  sparc32: Fix inverted invalid_frame_pointer checks on sigreturns
  sparc64: Fix find_node warning if numa node cannot be found
2016-11-21 13:56:17 -08:00
Alexey Dobriyan
32d84cdcfd netlink: smaller nla_attr_minlen table
Length of a netlink attribute may be u16 but lengths of basic attributes
are much smaller, so small we can save 16 bytes of .rodata and pocket
change inside .text.

16-bit is worse on x86-64 than 8-bit because of operand size override prefix.

	add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-19 (-19)
	function                                     old     new   delta
	validate_nla                                 418     417      -1
	nla_policy_len                                66      64      -2
	nla_attr_minlen                               32      16     -16
	Total: Before=154865051, After=154865032, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-19 22:11:25 -05:00
Jonathan Corbet
917fef6f7e Linux 4.9-rc4
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Merge tag 'v4.9-rc4' into sound

Bring in -rc4 patches so I can successfully merge the sound doc changes.
2016-11-18 16:13:41 -07:00
Babu Moger
e6b5f1be7a config: Adding the new config parameter CONFIG_PROVE_LOCKING_SMALL for sparc
This new config parameter limits the space used for "Lock debugging:
prove locking correctness" by about 4MB. The current sparc systems have
the limitation of 32MB size for kernel size including .text, .data and
.bss sections. With PROVE_LOCKING feature, the kernel size could grow
beyond this limit and causing system boot-up issues. With this option,
kernel limits the size of the entries of lock_chains, stack_trace etc.,
so that kernel fits in required size limit. This is not visible to user
and only used for sparc.

Signed-off-by: Babu Moger <babu.moger@oracle.com>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 11:33:19 -08:00
Abhi Das
680bb946a1 fix iov_iter_advance() for ITER_PIPE
iov_iter_advance() needs to decrement iter->count by the number of
bytes we'd moved beyond.  Normal flavours do that, but ITER_PIPE
doesn't and ITER_PIPE generic_file_read_iter() for O_DIRECT files
ends up with a bogus fallback to page cache read, resulting in incorrect
values for file offset and bytes read.

Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-11-17 00:00:48 -05:00
Christian Borntraeger
f2f09a4cee locking/core: Remove cpu_relax_lowlatency() users
With the s390 special case of a yielding cpu_relax() implementation gone,
we can now remove all users of cpu_relax_lowlatency() and replace them
with cpu_relax().

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/1477386195-32736-5-git-send-email-borntraeger@de.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-11-16 10:15:10 +01:00
Paul E. McKenney
6190aaafd0 Merge branches 'doc.2016.11.14a', 'fixes.2016.11.14a', 'list.2016.10.31a' and 'torture.2016.11.14a' into HEAD
doc.2016.11.14a:  Documentation changes
fixes.2016.11.14aneous fixes
list.2016.10.31a:  List updates
torture.2016.11.14a:  Torture-test updates
2016-11-14 10:50:50 -08:00
Nikolay Borisov
f2151a0a34 rcu: RCU_TRACE enables event tracing as well as debugfs
The commit brings the RCU_TRACE Kconfig option's help text up to date
by noting that it enables additional event tracing as well as debugfs.

Signed-off-by: Nikolay Borisov <kernel@kyup.com>
[ paulmck:  Do some wordsmithing. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2016-11-14 10:46:25 -08:00
Chris Wilson
ae65a21fb8 lib/stackdepot: export save/fetch stack for drivers
Some drivers would like to record stacktraces in order to aide leak
tracing.  As stackdepot already provides a facility for only storing the
unique traces, thereby reducing the memory required, export that
functionality for use by drivers.

The code was originally created for KASAN and moved under lib in commit
cd11016e5f521 ("mm, kasan: stackdepot implementation.  Enable stackdepot
for SLAB") so that it could be shared with mm/.  In turn, we want to
share it now with drivers.

Link: http://lkml.kernel.org/r/20161108133209.22704-1-chris@chris-wilson.co.uk
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-11-11 08:12:37 -08:00
Alexander Duyck
d29fa0cb76 swiotlb: Minor fix-ups for DMA_ATTR_SKIP_CPU_SYNC support
I am updating the paths so that instead of trying to pass
"attr | DMA_ATTR_SKIP_CPU_SYNC" we instead just OR the value into attr and
then pass it since attr will not be used after we make the unmap call.

I realized there was one spot I had missed when I was applying the DMA
attribute to the DMA mapping exception handling.  This change corrects that.

Finally it looks like there is a stray blank line at the end of the
swiotlb_unmap_sg_attrs function that can be dropped.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-10 15:56:19 -05:00
Sebastian Andrzej Siewior
d544abd5ff lib/radix-tree: Convert to hotplug state machine
Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161103145021.28528-6-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 23:45:27 +01:00
Sebastian Andrzej Siewior
5588f5afb4 lib/percpu_counter: Convert to hotplug state machine
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20161103145021.28528-5-bigeasy@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-11-09 23:45:26 +01:00
Gayatri Kammela
b9bf33a8bd lib/raid6: Add AVX2 optimized xor_syndrome functions
Implement the AVX2 optimization of RAID6 xor_syndrome functions which is
simply based on sse2.c written by hpa.

Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Yuanhan Liu <yuanhan.liu@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Signed-off-by: Gayatri Kammela <gayatri.kammela@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
2016-11-07 15:08:20 -08:00
Alexander Duyck
0443fa003f swiotlb: Add support for DMA_ATTR_SKIP_CPU_SYNC
As a first step to making DMA_ATTR_SKIP_CPU_SYNC apply to architectures
beyond just ARM I need to make it so that the swiotlb will respect the
flag.  In order to do that I also need to update the swiotlb-xen since it
heavily makes use of the functionality.

Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-07 15:06:33 -05:00
Alexander Duyck
ebcf6f979d swiotlb: Drop unused functions swiotlb_map_sg and swiotlb_unmap_sg
There are no users for swiotlb_map_sg or swiotlb_unmap_sg so we might as
well just drop them.

Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by:  Christoph Hellwig <hch@infradead.org>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-07 15:06:31 -05:00
Geert Uytterhoeven
0d2e18985a swiotlb: Rate-limit printing when running out of SW-IOMMU space
If the system runs out of SW-IOMMU space, changes are high successive
requests will fail, too, flooding the kernel log.  This is true
especially for streaming DMA, which is typically used repeatedly outside
the driver's initialization routine.  Add rate-limiting to fix this.

While at it, get rid of the open-coded dev_name() handling by using the
appropriate dev_err_*() variant.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Konrad Rzeszutek Wilk <konrad@kernel.org>
2016-11-07 15:06:26 -05:00
Christoph Hellwig
2f8b544477 block,fs: untangle fs.h and blk_types.h
Nothing in fs.h should require blk_types.h to be included.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2016-11-01 09:43:26 -06:00
Arnd Bergmann
4520bcb2ba bug: Avoid Kconfig warning for BUG_ON_DATA_CORRUPTION
The CONFIG_DEBUG_LIST option is normally meant for kernel developers
rather than production machines and is guarded by CONFIG_DEBUG_KERNEL.

In contrast, the newly added CONFIG_BUG_ON_DATA_CORRUPTION is meant
for security hardening and may be used on systems that intentionally
do not enable CONFIG_DEBUG_KERNEL. In this configuration, we get
a warning from Kconfig about the mismatched dependencies:

warning: (BUG_ON_DATA_CORRUPTION) selects DEBUG_LIST which has unmet direct dependencies (DEBUG_KERNEL)

This annotates the DEBUG_LIST option to be selectable by
BUG_ON_DATA_CORRUPTION when DEBUG_KERNEL is disabled.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 40cd725cfc7f ("bug: Provide toggle for BUG on data corruption")
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
2016-10-31 13:01:59 -07:00
Valentin Rothberg
91a6cee6e3 lib/Kconfig.debug: Fix typo in select statement
Commit 484f29c7430b3 ("bug: Provide toggle for BUG on data corruption")
added a Kconfig select statement on CONFIG_DEBUG_LIST, but the CONFIG_
prefix is only used in Make and C(PP) syntax.  Remove the CONFIG_ prefix
to correctly select the Kconfig option DEBUG_LIST.

Signed-off-by: Valentin Rothberg <valentinrothberg@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Kees Cook <keescook@chromium.org>
2016-10-31 13:01:59 -07:00
Kees Cook
de54ebbe26 bug: Provide toggle for BUG on data corruption
The kernel checks for cases of data structure corruption under some
CONFIGs (e.g. CONFIG_DEBUG_LIST). When corruption is detected, some
systems may want to BUG() immediately instead of letting the system run
with known corruption.  Usually these kinds of manipulation primitives can
be used by security flaws to gain arbitrary memory write control. This
provides a new config CONFIG_BUG_ON_DATA_CORRUPTION and a corresponding
macro CHECK_DATA_CORRUPTION for handling these situations. Notably, even
if not BUGing, the kernel should not continue processing the corrupted
structure.

This is inspired by similar hardening by Syed Rameez Mustafa in MSM
kernels, and in PaX and Grsecurity, which is likely in response to earlier
removal of the BUG calls in commit 924d9addb9b1 ("list debugging: use
WARN() instead of BUG()").

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
2016-10-31 13:01:58 -07:00
Kees Cook
0cd340dcb0 list: Split list_del() debug checking into separate function
Similar to the list_add() debug consolidation, this commit consolidates
the debug checking performed during CONFIG_DEBUG_LIST into a new
__list_del_entry_valid() function, and stops list updates when corruption
is found.

Refactored from same hardening in PaX and Grsecurity.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
2016-10-31 13:01:57 -07:00
Kees Cook
54acd4397d rculist: Consolidate DEBUG_LIST for list_add_rcu()
This commit consolidates the debug checking for list_add_rcu() into the
new single __list_add_valid() debug function.  Notably, this commit fixes
the sanity check that was added in commit 17a801f4bfeb ("list_debug:
WARN for adding something already in the list"), which wasn't checking
RCU-protected lists.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
2016-10-31 13:01:57 -07:00
Kees Cook
d7c816733d list: Split list_add() debug checking into separate function
Right now, __list_add() code is repeated either in list.h or in
list_debug.c, but the only differences between the two versions
are the debug checks. This commit therefore extracts these debug
checks into a separate __list_add_valid() function and consolidates
__list_add(). Additionally this new __list_add_valid() function will stop
list manipulations if a corruption is detected, instead of allowing for
further corruption that may lead to even worse conditions.

This is slight refactoring of the same hardening done in PaX and Grsecurity.

Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Rik van Riel <riel@redhat.com>
2016-10-31 13:01:56 -07:00
Greg Kroah-Hartman
bb41d2a51f Merge 4.9-rc3 into driver-core-next
We want the fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-30 06:43:43 -04:00
Linus Torvalds
2a26d99b25 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:
 "Lots of fixes, mostly drivers as is usually the case.

   1) Don't treat zero DMA address as invalid in vmxnet3, from Alexey
      Khoroshilov.

   2) Fix element timeouts in netfilter's nft_dynset, from Anders K.
      Pedersen.

   3) Don't put aead_req crypto struct on the stack in mac80211, from
      Ard Biesheuvel.

   4) Several uninitialized variable warning fixes from Arnd Bergmann.

   5) Fix memory leak in cxgb4, from Colin Ian King.

   6) Fix bpf handling of VLAN header push/pop, from Daniel Borkmann.

   7) Several VRF semantic fixes from David Ahern.

   8) Set skb->protocol properly in ip6_tnl_xmit(), from Eli Cooper.

   9) Socket needs to be locked in udp_disconnect(), from Eric Dumazet.

  10) Div-by-zero on 32-bit fix in mlx4 driver, from Eugenia Emantayev.

  11) Fix stale link state during failover in NCSCI driver, from Gavin
      Shan.

  12) Fix netdev lower adjacency list traversal, from Ido Schimmel.

  13) Propvide proper handle when emitting notifications of filter
      deletes, from Jamal Hadi Salim.

  14) Memory leaks and big-endian issues in rtl8xxxu, from Jes Sorensen.

  15) Fix DESYNC_FACTOR handling in ipv6, from Jiri Bohac.

  16) Several routing offload fixes in mlxsw driver, from Jiri Pirko.

  17) Fix broadcast sync problem in TIPC, from Jon Paul Maloy.

  18) Validate chunk len before using it in SCTP, from Marcelo Ricardo
      Leitner.

  19) Revert a netns locking change that causes regressions, from Paul
      Moore.

  20) Add recursion limit to GRO handling, from Sabrina Dubroca.

  21) GFP_KERNEL in irq context fix in ibmvnic, from Thomas Falcon.

  22) Avoid accessing stale vxlan/geneve socket in data path, from
      Pravin Shelar"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (189 commits)
  geneve: avoid using stale geneve socket.
  vxlan: avoid using stale vxlan socket.
  qede: Fix out-of-bound fastpath memory access
  net: phy: dp83848: add dp83822 PHY support
  enic: fix rq disable
  tipc: fix broadcast link synchronization problem
  ibmvnic: Fix missing brackets in init_sub_crq_irqs
  ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context
  Revert "ibmvnic: Fix releasing of sub-CRQ IRQs in interrupt context"
  arch/powerpc: Update parameters for csum_tcpudp_magic & csum_tcpudp_nofold
  net/mlx4_en: Save slave ethtool stats command
  net/mlx4_en: Fix potential deadlock in port statistics flow
  net/mlx4: Fix firmware command timeout during interrupt test
  net/mlx4_core: Do not access comm channel if it has not yet been initialized
  net/mlx4_en: Fix panic during reboot
  net/mlx4_en: Process all completions in RX rings after port goes up
  net/mlx4_en: Resolve dividing by zero in 32-bit system
  net/mlx4_core: Change the default value of enable_qos
  net/mlx4_core: Avoid setting ports to auto when only one port type is supported
  net/mlx4_core: Fix the resource-type enum in res tracker to conform to FW spec
  ...
2016-10-29 20:33:20 -07:00
Julia Lawall
edbbf994bd kobject: improve function-level documentation
In the first case, rename the second variable to correspond to the name
found in the function parameter list.

In the remaining cases, reorder the variables to correspond to their order
in the parameter list.

Issue detected using Coccinelle (http://coccinelle.lip6.fr/)

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-10-28 02:42:10 -04:00
Daniel Mentz
62e931fac4 lib/genalloc.c: start search from start of chunk
gen_pool_alloc_algo() iterates over the chunks of a pool trying to find
a contiguous block of memory that satisfies the allocation request.

The shortcut

	if (size > atomic_read(&chunk->avail))
		continue;

makes the loop skip over chunks that do not have enough bytes left to
fulfill the request.  There are two situations, though, where an
allocation might still fail:

(1) The available memory is not contiguous, i.e.  the request cannot
    be fulfilled due to external fragmentation.

(2) A race condition.  Another thread runs the same code concurrently
    and is quicker to grab the available memory.

In those situations, the loop calls pool->algo() to search the entire
chunk, and pool->algo() returns some value that is >= end_bit to
indicate that the search failed.  This return value is then assigned to
start_bit.  The variables start_bit and end_bit describe the range that
should be searched, and this range should be reset for every chunk that
is searched.  Today, the code fails to reset start_bit to 0.  As a
result, prefixes of subsequent chunks are ignored.  Memory allocations
might fail even though there is plenty of room left in these prefixes of
those other chunks.

Fixes: 7f184275aa30 ("lib, Make gen_pool memory allocator lockless")
Link: http://lkml.kernel.org/r/1477420604-28918-1-git-send-email-danielmentz@google.com
Signed-off-by: Daniel Mentz <danielmentz@google.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-27 18:43:43 -07:00
Dmitry Vyukov
02754e0a48 lib/stackdepot.c: bump stackdepot capacity from 16MB to 128MB
KASAN uses stackdepot to memorize stacks for all kmalloc/kfree calls.
Current stackdepot capacity is 16MB (1024 top level entries x 4 pages on
second level).  Size of each stack is (num_frames + 3) * sizeof(long).
Which gives us ~84K stacks.  This capacity was chosen empirically and it
is enough to run kernel normally.

However, when lots of configs are enabled and a fuzzer tries to maximize
code coverage, it easily hits the limit within tens of minutes.  I've
tested for long a time with number of top level entries bumped 4x
(4096).  And I think I've seen overflow only once.  But I don't have all
configs enabled and code coverage has not reached maximum yet.  So bump
it 8x to 8192.

Since we have two-level table, memory cost of this is very moderate --
currently the top-level table is 8KB, with this patch it is 64KB, which
is negligible under KASAN.

Here is some approx math.

128MB allows us to memorize ~670K stacks (assuming stack is ~200b).
I've grepped kernel for kmalloc|kfree|kmem_cache_alloc|kmem_cache_free|
kzalloc|kstrdup|kstrndup|kmemdup and it gives ~60K matches.  Most of
alloc/free call sites are reachable with only one stack.  But some
utility functions can have large fanout.  Assuming average fanout is 5x,
total number of alloc/free stacks is ~300K.

Link: http://lkml.kernel.org/r/1476458416-122131-1-git-send-email-dvyukov@google.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Baozeng Ding <sploving1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-27 18:43:43 -07:00