Several people have reported occasionally seeing processes stuck in
compact_zone(), even triggering soft lockups, in 3.18-rc2+.

Testing a revert of commit e14c720e ("mm, compaction: remember
position within pageblock in free pages scanner") fixed the issue,
although the stuck processes do not appear to involve the free scanner.

Finally, by code inspection, the bug was found in isolate_migratepages()
which uses a slightly different condition to detect if the migration and
free scanners have met, than compact_finished().  That has not been a
problem until commit e14c720e allowed the free scanner position
between individual invocations to be in the middle of a pageblock.

In a relatively rare case, the migration scanner position can end up at
the beginning of a pageblock, with the free scanner position in the
middle of the same pageblock.  If it's the migration scanner's turn,
isolate_migratepages() exits immediately (without updating the
position), while compact_finished() decides to continue compaction,
resulting in a potentially infinite loop.  The system can recover only
if another process creates enough high-order pages to make the watermark
checks in compact_finished() pass.

This patch fixes the immediate problem by bumping the migration
scanner's position to meet the free scanner in isolate_migratepages(),
when both are within the same pageblock.  This causes compact_finished()
to terminate properly.  A more robust check in compact_finished() is
planned as a cleanup for better future maintainability.

Fixes: e14c720e ("mm, compaction: remember position within pageblock in free pages scanner)
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: P. Christeas <xrg@linux.gr>
Tested-by: P. Christeas <xrg@linux.gr>
Link: http://marc.info/?l=linux-mm&m=141508604232522&w=2Reported-by: Norbert Preining <preining@logic.at>
Tested-by: Norbert Preining <preining@logic.at>
Link: https://lkml.org/lkml/2014/11/4/904Reported-by: Pavel Machek <pavel@ucw.cz>
Link: https://lkml.org/lkml/2014/11/7/164
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Having test_pages_isolated failure message as a warning confuses users
into thinking that it is more serious than it really is.  In reality, if
called via CMA, allocation will be retried so a single
test_pages_isolated failure does not prevent allocation from succeeding.

Demote the warning message to an info message and reformat it such that
the text "failed" does not appear and instead a less worrying "PFNS
busy" is used.

This message is trivially reproducible on a 10GB x86 machine on 3.16.y
kernels configured with CONFIG_DMA_CMA.
Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Peter Hurley <peter@hurleysoftware.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Unlike SLUB, sometimes, object isn't started at the beginning of the
slab in SLAB.  This causes the unalignment problem after slab merging is
supported by commit 12220dea ("mm/slab: support slab merge").

Following is the report from Markos that fail to boot on Malta with EVA.

    Calibrating delay loop... 19.86 BogoMIPS (lpj=99328)
    pid_max: default: 32768 minimum: 301
    Mount-cache hash table entries: 4096 (order: 0, 16384 bytes)
    Mountpoint-cache hash table entries: 4096 (order: 0, 16384 bytes)
    Kernel bug detected[#1]:
    CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.17.0-05639-g12220dea #1631
    task: 1f04f5d8 ti: 1f050000 task.ti: 1f050000
    epc   : 80141190 alloc_unbound_pwq+0x234/0x304
        Not tainted
    ra    : 80141184 alloc_unbound_pwq+0x228/0x304
    Process swapper/0 (pid: 1, threadinfo=1f050000, task=1f04f5d8, tls=00000000)
    Call Trace:
      alloc_unbound_pwq+0x234/0x304
      apply_workqueue_attrs+0x11c/0x294
      __alloc_workqueue_key+0x23c/0x470
      init_workqueues+0x320/0x400
      do_one_initcall+0xe8/0x23c
      kernel_init_freeable+0x9c/0x224
      kernel_init+0x10/0x100
      ret_from_kernel_thread+0x14/0x1c
    [ end trace cb88537fdc8fa200 ]
    Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b

alloc_unbound_pwq() allocates slab object from pool_workqueue.  This
kmem_cache requires 256 bytes alignment, but, current merging code
doesn't honor that, and merge it with kmalloc-256.  kmalloc-256 requires
only cacheline size alignment so that above failure occurs.  However, in
x86, kmalloc-256 is luckily aligned in 256 bytes, so the problem didn't
happen on it.

To fix this problem, this patch introduces alignment mismatch check in
find_mergeable().  This will fix the problem.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Reported-by: Markos Chandras <Markos.Chandras@imgtec.com>
Tested-by: Markos Chandras <Markos.Chandras@imgtec.com>
Acked-by: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Current pageblock isolation logic could isolate each pageblock
individually.  This causes freepage accounting problem if freepage with
pageblock order on isolate pageblock is merged with other freepage on
normal pageblock.  We can prevent merging by restricting max order of
merging to pageblock order if freepage is on isolate pageblock.

A side-effect of this change is that there could be non-merged buddy
freepage even if finishing pageblock isolation, because undoing
pageblock isolation is just to move freepage from isolate buddy list to
normal buddy list rather than to consider merging.  So, the patch also
makes undoing pageblock isolation consider freepage merge.  When
un-isolation, freepage with more than pageblock order and it's buddy are
checked.  If they are on normal pageblock, instead of just moving, we
isolate the freepage and free it in order to get merged.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Heesub Shin <heesub.shin@samsung.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Ritesh Harjani <ritesh.list@gmail.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

All the caller of __free_one_page() has similar freepage counting logic,
so we can move it to __free_one_page().  This reduce line of code and
help future maintenance.

This is also preparation step for "mm/page_alloc: restrict max order of
merging on isolated pageblock" which fix the freepage counting problem
on freepage with more than pageblock order.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Heesub Shin <heesub.shin@samsung.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Ritesh Harjani <ritesh.list@gmail.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In free_pcppages_bulk(), we use cached migratetype of freepage to
determine type of buddy list where freepage will be added.  This
information is stored when freepage is added to pcp list, so if
isolation of pageblock of this freepage begins after storing, this
cached information could be stale.  In other words, it has original
migratetype rather than MIGRATE_ISOLATE.

There are two problems caused by this stale information.

One is that we can't keep these freepages from being allocated.
Although this pageblock is isolated, freepage will be added to normal
buddy list so that it could be allocated without any restriction.  And
the other problem is incorrect freepage accounting.  Freepages on
isolate pageblock should not be counted for number of freepage.

Following is the code snippet in free_pcppages_bulk().

    /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
    __free_one_page(page, page_to_pfn(page), zone, 0, mt);
    trace_mm_page_pcpu_drain(page, 0, mt);
    if (likely(!is_migrate_isolate_page(page))) {
        __mod_zone_page_state(zone, NR_FREE_PAGES, 1);
        if (is_migrate_cma(mt))
            __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, 1);
    }

As you can see above snippet, current code already handle second
problem, incorrect freepage accounting, by re-fetching pageblock
migratetype through is_migrate_isolate_page(page).

But, because this re-fetched information isn't used for
__free_one_page(), first problem would not be solved.  This patch try to
solve this situation to re-fetch pageblock migratetype before
__free_one_page() and to use it for __free_one_page().

In addition to move up position of this re-fetch, this patch use
optimization technique, re-fetching migratetype only if there is isolate
pageblock.  Pageblock isolation is rare event, so we can avoid
re-fetching in common case with this optimization.

This patch also correct migratetype of the tracepoint output.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Heesub Shin <heesub.shin@samsung.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Ritesh Harjani <ritesh.list@gmail.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Before describing bugs itself, I first explain definition of freepage.

 1. pages on buddy list are counted as freepage.
 2. pages on isolate migratetype buddy list are *not* counted as freepage.
 3. pages on cma buddy list are counted as CMA freepage, too.

Now, I describe problems and related patch.

Patch 1: There is race conditions on getting pageblock migratetype that
it results in misplacement of freepages on buddy list, incorrect
freepage count and un-availability of freepage.

Patch 2: Freepages on pcp list could have stale cached information to
determine migratetype of buddy list to go.  This causes misplacement of
freepages on buddy list and incorrect freepage count.

Patch 4: Merging between freepages on different migratetype of
pageblocks will cause freepages accouting problem.  This patch fixes it.

Without patchset [3], above problem doesn't happens on my CMA allocation
test, because CMA reserved pages aren't used at all.  So there is no
chance for above race.

With patchset [3], I did simple CMA allocation test and get below
result:

 - Virtual machine, 4 cpus, 1024 MB memory, 256 MB CMA reservation
 - run kernel build (make -j16) on background
 - 30 times CMA allocation(8MB * 30 = 240MB) attempts in 5 sec interval
 - Result: more than 5000 freepage count are missed

With patchset [3] and this patchset, I found that no freepage count are
missed so that I conclude that problems are solved.

On my simple memory offlining test, these problems also occur on that
environment, too.

This patch (of 4):

There are two paths to reach core free function of buddy allocator,
__free_one_page(), one is free_one_page()->__free_one_page() and the
other is free_hot_cold_page()->free_pcppages_bulk()->__free_one_page().
Each paths has race condition causing serious problems.  At first, this
patch is focused on first type of freepath.  And then, following patch
will solve the problem in second type of freepath.

In the first type of freepath, we got migratetype of freeing page
without holding the zone lock, so it could be racy.  There are two cases
of this race.

 1. pages are added to isolate buddy list after restoring orignal
    migratetype

    CPU1                                   CPU2

    get migratetype => return MIGRATE_ISOLATE
    call free_one_page() with MIGRATE_ISOLATE

                                grab the zone lock
                                unisolate pageblock
                                release the zone lock

    grab the zone lock
    call __free_one_page() with MIGRATE_ISOLATE
    freepage go into isolate buddy list,
    although pageblock is already unisolated

This may cause two problems.  One is that we can't use this page anymore
until next isolation attempt of this pageblock, because freepage is on
isolate buddy list.  The other is that freepage accouting could be wrong
due to merging between different buddy list.  Freepages on isolate buddy
list aren't counted as freepage, but ones on normal buddy list are
counted as freepage.  If merge happens, buddy freepage on normal buddy
list is inevitably moved to isolate buddy list without any consideration
of freepage accouting so it could be incorrect.

 2. pages are added to normal buddy list while pageblock is isolated.
    It is similar with above case.

This also may cause two problems.  One is that we can't keep these
freepages from being allocated.  Although this pageblock is isolated,
freepage would be added to normal buddy list so that it could be
allocated without any restriction.  And the other problem is same as
case 1, that it, incorrect freepage accouting.

This race condition would be prevented by checking migratetype again
with holding the zone lock.  Because it is somewhat heavy operation and
it isn't needed in common case, we want to avoid rechecking as much as
possible.  So this patch introduce new variable, nr_isolate_pageblock in
struct zone to check if there is isolated pageblock.  With this, we can
avoid to re-check migratetype in common case and do it only if there is
isolated pageblock or migratetype is MIGRATE_ISOLATE.  This solve above
mentioned problems.

Changes from v3:
Add one more check in free_one_page() that checks whether migratetype is
MIGRATE_ISOLATE or not. Without this, abovementioned case 1 could happens.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: Minchan Kim <minchan@kernel.org>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Tang Chen <tangchen@cn.fujitsu.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Heesub Shin <heesub.shin@samsung.com>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Cc: Ritesh Harjani <ritesh.list@gmail.com>
Cc: Gioh Kim <gioh.kim@lge.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Commit 7d49d886 ("mm, compaction: reduce zone checking frequency in
the migration scanner") has a side-effect that changes the iteration
range calculation.  Before the change, block_end_pfn is calculated using
start_pfn, but now it blindly adds pageblock_nr_pages to the previous
value.

This causes the problem that isolation_start_pfn is larger than
block_end_pfn when we isolate the page with more than pageblock order.
In this case, isolation would fail due to an invalid range parameter.

To prevent this, this patch implements skipping the range until a proper
target pageblock is met.  Without this patch, CMA with more than
pageblock order always fails but with this patch it will succeed.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

zram could kunmap_atomic() a NULL pointer in a rare situation: a zram
page becomes a full-zeroed page after a partial write io.  The current
code doesn't handle this case and performs kunmap_atomic() on a NULL
pointer, which panics the kernel.

This patch fixes this issue.
Signed-off-by: Weijie Yang <weijie.yang@samsung.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Cc: Weijie Yang <weijie.yang.kh@gmail.com>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull SELinux fixlet from James Morris:
 "WARN_ONCE() here will unnecessarily terrify users"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  selinux: convert WARN_ONCE() to printk() in selinux_nlmsg_perm()

Pull audit fixes from Paul Moore:
 "After he sent the initial audit pull request for 3.18, Eric asked me
  to take over the management of the audit tree, hence this pull request
  to fix a couple of problems with audit.

  As you can see below, the changes are minimal: adding some whitespace
  to a string so userspace parses it correctly, and fixing a problem
  with audit's usage of fsnotify that was causing audit watch rules to
  be lost.  Neither of these patches were very controversial on the
  mailing lists and they fix real problems, getting them into 3.18 would
  be a good thing"

* 'stable-3.18' of git://git.infradead.org/users/pcmoore/audit:
  audit: keep inode pinned
  audit: AUDIT_FEATURE_CHANGE message format missing delimiting space

Pull device mapper fixes from Mike Snitzer:

 - stable fix for dm-thin that avoids normal IO racing with discard

 - stable fix for a dm-cache related bug in dm-btree walking code that
   results from using very large fast device (eg 4T) with a very small
   cache blocksize (eg 32K) -- this is a very uncommon configuration

 - a couple fixes for dm-raid (one for stable and the other addresses a
   crash in 3.18-rc1 code)

 - stable fix for dm-thinp that addresses a very rare dm-bufio bug
   having to do with memory reclaimation (via shrinker) when using
   dm-thinp ontop of loopback devices

 - fix a leak in dm-stripe target constructor's error path

* tag 'dm-3.18-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm btree: fix a recursion depth bug in btree walking code
  dm thin: grab a virtual cell before looking up the mapping
  dm raid: fix inaccessible superblocks causing oops in configure_discard_support
  dm raid: ensure superblock's size matches device's logical block size
  dm bufio: change __GFP_IO to __GFP_FS in shrinker callbacks
  dm stripe: fix potential for leak in stripe_ctr error path

Pull kvm fixes from Paolo Bonzini:
 "Two fixes --- one of them not exactly a one liner, but things are
  calming down on the KVM front at last"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86: Fix uninitialized op->type for some immediate values
  KVM: s390: virtio_ccw: remove unused variable

Pull Xtensa fixes from Chris Zankel:
 - fix umount syscall
 - fix ISS and xtfpga Kconfig dependencies so that more randconfigs are
   buildable
 - add seccomp, getrandom, and memfd_create syscalls
 - add defconfigs for KC705 and SMP LX200
 - implement pgprot_noncached

* tag 'xtensa-20141109' of git://github.com/czankel/xtensa-linux:
  xtensa: xtfpga: add lx200 SMP DTS and defconfig
  xtensa: xtfpga: add generic KC705 board config
  xtensa: re-wire umount syscall to sys_oldumount
  xtensa: xtfpga: only select ethoc when ethernet is available
  xtensa: add seccomp, getrandom, and memfd_create syscalls
  xtensa: ISS: add BLOCK dependency to BLK_DEV_SIMDISK
  xtensa: implement pgprot_noncached
  xtensa/uapi: Add definition of TIOC[SG]RS485

Pull crypto fixes from Herbert Xu:
 - stack corruption fix for pseries hwrng driver
 - add missing DMA unmap in caam crypto driver
 - fix NUMA crash in qat crypto driver
 - fix buggy mapping of zero-length associated data in qat crypto driver

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  hwrng: pseries - port to new read API and fix stack corruption
  crypto: caam - fix missing dma unmap on error path
  crypto: qat - Enforce valid numa configuration
  crypto: qat - Prevent dma mapping zero length assoc data

Merge tag 'trace-fixes-v3.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fix from Steven Rostedt:
 "Rabin Vincent found a way that tracing could cause an infinite loop in
  the kernel.  The splice logic wants a full page from the ring buffer
  but the ring_buffer_wait() returns when there's any data in the ring
  buffer.  The splice code would then continue the loop waiting for a
  full page.  But if a full page never happens, the splice code will
  never sleep and just continue to loop.

  There's another case that Rabin fixed that could loop if there's no
  memory and kmalloc() constantly returns NULL"

* tag 'trace-fixes-v3.18-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  tracing: Do not risk busy looping in buffer splice
  tracing: Do not busy wait in buffer splice

Pull kernel argument parsing fix from Rusty Russell:
 "Nasty, stupid bug, and I've suddenly had two reports"

* tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  param: fix crash on bad kernel arguments

Merge tag 'hwmon-for-linus-v3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 - fix PCI device ID in fam15h_power driver
 - fix suspend/resume behavior in pwm-fan driver
 - reduce logging noise created by ibmpowernv driver

* tag 'hwmon-for-linus-v3.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (fam15h_power) Fix NB device ID for F16h M30h
  hwmon: (pwm-fan) Fix suspend/resume behavior
  hwmon: (ibmpowernv) Quieten when probing finds no device

Pull thermal driver fixes from Eduardo Valentin:
 "This week we have few fixes:
   - fix in IMX thermal driver to do the correct loading sequence with
     CPUfreq
   - fix in Exynos related to TMU_CONTROL offset in Exynos5260
   - fix the unit conversion in int3403"

[ Still pulling from Eduardo as Rui Zhang is on a business trip and has
  troubles with his machine ]

* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal:
  imx: thermal: imx_get_temp might be called before sensor clock is prepared
  thermal: exynos: use correct offset for TMU_CONTROL register on Exynos5260
  thermal: imx: correct driver load sequence for cpu cooling
  Thermal/int3403: Fix thermal hysteresis unit conversion

Convert WARN_ONCE() to printk() in selinux_nlmsg_perm().

After conversion from audit_log() in commit e173fb26, WARN_ONCE() was
deemed too alarmist, so switch it to printk().
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
[PM: Changed to printk(WARNING) so we catch all of the different
 invalid netlink messages.  In Richard's defense, he brought this
 point up earlier, but I didn't understand his point at the time.]
Signed-off-by: Paul Moore <pmoore@redhat.com>

Pull MFD fixes from Lee Jones:
 - register offset fix for stmpe
 - eradicate build warning when !PM in rtsx_pcr
 - fix device ID collision when multiple boards are connected in
   viperboard
 - use correct Regmap handle - fixing unhanded IRQs in max77693
 - unmask MUIC IRQs in max77693
 - clear VBUS & CHG bits so board doesn't reboot instead of poweroff in
   twl4030

* tag 'mfd-fixes-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd:
  mfd: twl4030-power: Fix poweroff with PM configuration enabled
  mfd: max77693: Fix always masked MUIC interrupts
  mfd: max77693: Use proper regmap for handling MUIC interrupts
  mfd: viperboard: Fix platform-device id collision
  mfd: rtsx: Fix build warnings for !PM
  mfd: stmpe: Fix STMPE24xx GPMR LSB

Pull drm fixes from Dave Airlie:
 "Radeon and i915 fixes.

  I probably should have sent these earlier, but nothing too urgent in
  them:

   - i915:
        blackscreen and corruption fixes
   - radeon:
        oops, locking and stability"

* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux:
  drm/radeon: add missing crtc unlock when setting up the MC
  drm/radeon: use gart for DMA IB tests
  drm/radeon: make sure mode init is complete in bandwidth_update
  drm/radeon: set correct CE ram size for CIK
  drm/i915: safeguard against too high minimum brightness
  drm/i915: vlv: fix gunit HW state corruption during S4 suspend
  drm/i915: Disable caches for Global GTT.

Audit rules disappear when an inode they watch is evicted from the cache.
This is likely not what we want.

The guilty commit is "fsnotify: allow marks to not pin inodes in core",
which didn't take into account that audit_tree adds watches with a zero
mask.

Adding any mask should fix this.

Fixes: 90b1e7a5 ("fsnotify: allow marks to not pin inodes in core")
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org # 2.6.36+
Signed-off-by: Paul Moore <pmoore@redhat.com>

F3 device ID is wrongly included in fam15h_power_id_table
for F16h M30h. It should be F4 device ID. Fix this.
Signed-off-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@amd.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

The state of a PWM output is not clearly defined after resume. Some PWM
drivers do not restore the duty cycle upon resume, thus it is necessary to
manually restore the correct value.
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Because we build kernels with drivers built in for many platforms, it's
normal for the ibmpowernv driver to be loaded on systems that don't have
the appropriate hardware.

Currently the driver spams the log with:

  ibmpowernv ibmpowernv.0: Opal node 'sensors' not found
  ibmpowernv: Platfrom driver probe failed

But there is no error, this machine is not a powernv and doesn't have
the hardware. So change the sensors message to dev_dbg(), and only print
an error about the probe failing if it's not ENODEV.

Also fix the spelling of "Platfrom" and print the actual error value.
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Currently if the user passes an invalid value on the kernel command line
then the kernel will crash during argument parsing. On most systems this
is very hard to debug because the console hasn't been initialized yet.

This is a regression due to commit 51e158c1 ("param: hand arguments
after -- straight to init") which, in response to the systemd debug
controversy, made it possible to explicitly pass arguments to init. To
achieve this parse_args() was extended from simply returning an error
code to returning a pointer. Regretably the new init args logic does not
perform a proper validity check on the pointer resulting in a crash.

This patch fixes the validity check. Should the check fail then no arguments
will be passed to init. This is reasonable and matches how the kernel treats
its own arguments (i.e. no error recovery).
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: stable@vger.kernel.org
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

If the read loop in trace_buffers_splice_read() keeps failing due to
memory allocation failures without reading even a single page then this
function will keep busy looping.

Remove the risk for that by exiting the function if memory allocation
failures are seen.

Link: http://lkml.kernel.org/r/1415309167-2373-2-git-send-email-rabin@rab.inSigned-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

On a !PREEMPT kernel, attempting to use trace-cmd results in a soft
lockup:

 # trace-cmd record -e raw_syscalls:* -F false
 NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [trace-cmd:61]
 ...
 Call Trace:
  [<ffffffff8105b580>] ? __wake_up_common+0x90/0x90
  [<ffffffff81092e25>] wait_on_pipe+0x35/0x40
  [<ffffffff810936e3>] tracing_buffers_splice_read+0x2e3/0x3c0
  [<ffffffff81093300>] ? tracing_stats_read+0x2a0/0x2a0
  [<ffffffff812d10ab>] ? _raw_spin_unlock+0x2b/0x40
  [<ffffffff810dc87b>] ? do_read_fault+0x21b/0x290
  [<ffffffff810de56a>] ? handle_mm_fault+0x2ba/0xbd0
  [<ffffffff81095c80>] ? trace_event_buffer_lock_reserve+0x40/0x80
  [<ffffffff810951e2>] ? trace_buffer_lock_reserve+0x22/0x60
  [<ffffffff81095c80>] ? trace_event_buffer_lock_reserve+0x40/0x80
  [<ffffffff8112415d>] do_splice_to+0x6d/0x90
  [<ffffffff81126971>] SyS_splice+0x7c1/0x800
  [<ffffffff812d1edd>] tracesys_phase2+0xd3/0xd8

The problem is this: tracing_buffers_splice_read() calls
ring_buffer_wait() to wait for data in the ring buffers.  The buffers
are not empty so ring_buffer_wait() returns immediately.  But
tracing_buffers_splice_read() calls ring_buffer_read_page() with full=1,
meaning it only wants to read a full page.  When the full page is not
available, tracing_buffers_splice_read() tries to wait again with
ring_buffer_wait(), which again returns immediately, and so on.

Fix this by adding a "full" argument to ring_buffer_wait() which will
make ring_buffer_wait() wait until the writer has left the reader's
page, i.e.  until full-page reads will succeed.

Link: http://lkml.kernel.org/r/1415645194-25379-1-git-send-email-rabin@rab.in

Cc: stable@vger.kernel.org # 3.16+
Fixes: b1169cc6 ("tracing: Remove mock up poll wait function")
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

The walk code was using a 'ro_spine' to hold it's locked btree nodes.
But this data structure is designed for the rolling lock scheme, and
as such automatically unlocks blocks that are two steps up the call
chain.  This is not suitable for the simple recursive walk algorithm,
which retraces its steps.

This code is only used by the persistent array code, which in turn is
only used by dm-cache.  In order to trigger it you need to have a
mapping tree that is more than 2 levels deep; which equates to 8-16
million cache blocks.  For instance a 4T ssd with a very small block
size of 32k only just triggers this bug.

The fix just places the locked blocks on the stack, and stops using
the ro_spine altogether.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org

Commit e7cd1d1e ("mfd: twl4030-power: Add generic reset
configuration") enabled configuring the PM features for twl4030.

This caused poweroff command to fail on devices that have the
BCI charger on twl4030 wired, or have power wired for VBUS.
Instead of powering off, the device reboots. This is because
voltage is detected on charger or VBUS with the default bits
enabled for the power transition registers.

To fix the issue, let's just clear VBUS and CHG bits as we want
poweroff command to keep the system powered off.

Fixes: e7cd1d1e ("mfd: twl4030-power: Add generic reset configuration")
Cc: stable@vger.kernel.org # v3.16+
Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

All interrupts coming from MUIC were ignored because interrupt source
register was masked.

The Maxim 77693 has a "interrupt source" - a separate register and interrupts
which give information about PMIC block triggering the individual
interrupt (charger, topsys, MUIC, flash LED).

By default bootloader could initialize this register to "mask all"
value. In such case (observed on Trats2 board) MUIC interrupts won't be
generated regardless of their mask status. Regmap irq chip was unmasking
individual MUIC interrupts but the source was masked

Before introducing regmap irq chip this interrupt source was unmasked,
read and acked. Reading and acking is not necessary but unmasking is.

Fixes: 342d669c ("mfd: max77693: Handle IRQs using regmap")

Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Interrupts coming from Maxim77693 MUIC block (MicroUSB Interface
Controller) were not handled at all because wrong regmap was used for
MUIC's regmap_irq_chip.

The MUIC component of Maxim 77693 uses different I2C address thus second
regmap is created and used by max77693 extcon driver. The registers for
MUIC interrupts are also in that block and should be handled by that
second regmap.

However the regmap irq chip for MUIC was configured with default regmap
which could not read MUIC registers.

Fixes: 342d669c ("mfd: max77693: Handle IRQs using regmap")

Cc: <stable@vger.kernel.org>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Allow more than one viperboard to be connected by registering with
PLATFORM_DEVID_AUTO instead of PLATFORM_DEVID_NONE.

The subdevices are currently registered with PLATFORM_DEVID_NONE, which
will cause a name collision on the platform bus when a second viperboard
is plugged in:

viperboard 1-2.4:1.0: version 0.00 found at bus 001 address 004
------------[ cut here ]------------
WARNING: CPU: 0 PID: 181 at /home/johan/work/omicron/src/linux/fs/sysfs/dir.c:31 sysfs_warn_dup+0x74/0x84()
sysfs: cannot create duplicate filename '/bus/platform/devices/viperboard-gpio'
Modules linked in: i2c_viperboard viperboard netconsole [last unloaded: viperboard]
CPU: 0 PID: 181 Comm: bash Tainted: G        W      3.17.0-rc6 #1
[<c0016bf4>] (unwind_backtrace) from [<c0013860>] (show_stack+0x20/0x24)
[<c0013860>] (show_stack) from [<c04305f8>] (dump_stack+0x24/0x28)
[<c04305f8>] (dump_stack) from [<c0040fb4>] (warn_slowpath_common+0x80/0x98)
[<c0040fb4>] (warn_slowpath_common) from [<c004100c>] (warn_slowpath_fmt+0x40/0x48)
[<c004100c>] (warn_slowpath_fmt) from [<c016f1bc>] (sysfs_warn_dup+0x74/0x84)
[<c016f1bc>] (sysfs_warn_dup) from [<c016f548>] (sysfs_do_create_link_sd.isra.2+0xcc/0xd0)
[<c016f548>] (sysfs_do_create_link_sd.isra.2) from [<c016f588>] (sysfs_create_link+0x3c/0x48)
[<c016f588>] (sysfs_create_link) from [<c02867ec>] (bus_add_device+0x12c/0x1e0)
[<c02867ec>] (bus_add_device) from [<c0284820>] (device_add+0x410/0x584)
[<c0284820>] (device_add) from [<c0289440>] (platform_device_add+0xd8/0x26c)
[<c0289440>] (platform_device_add) from [<c02a5ae4>] (mfd_add_device+0x240/0x344)
[<c02a5ae4>] (mfd_add_device) from [<c02a5ce0>] (mfd_add_devices+0xb8/0x110)
[<c02a5ce0>] (mfd_add_devices) from [<bf00d1c8>] (vprbrd_probe+0x160/0x1b0 [viperboard])
[<bf00d1c8>] (vprbrd_probe [viperboard]) from [<c030c000>] (usb_probe_interface+0x1bc/0x2a8)
[<c030c000>] (usb_probe_interface) from [<c028768c>] (driver_probe_device+0x14c/0x3ac)
[<c028768c>] (driver_probe_device) from [<c02879e4>] (__driver_attach+0xa4/0xa8)
[<c02879e4>] (__driver_attach) from [<c0285698>] (bus_for_each_dev+0x70/0xa4)
[<c0285698>] (bus_for_each_dev) from [<c0287030>] (driver_attach+0x2c/0x30)
[<c0287030>] (driver_attach) from [<c030a288>] (usb_store_new_id+0x170/0x1ac)
[<c030a288>] (usb_store_new_id) from [<c030a2f8>] (new_id_store+0x34/0x3c)
[<c030a2f8>] (new_id_store) from [<c02853ec>] (drv_attr_store+0x30/0x3c)
[<c02853ec>] (drv_attr_store) from [<c016eaa8>] (sysfs_kf_write+0x5c/0x60)
[<c016eaa8>] (sysfs_kf_write) from [<c016dc68>] (kernfs_fop_write+0xd4/0x194)
[<c016dc68>] (kernfs_fop_write) from [<c010fe40>] (vfs_write+0xb4/0x1c0)
[<c010fe40>] (vfs_write) from [<c01104a8>] (SyS_write+0x4c/0xa0)
[<c01104a8>] (SyS_write) from [<c000f900>] (ret_fast_syscall+0x0/0x48)
---[ end trace 98e8603c22d65817 ]---
viperboard 1-2.4:1.0: Failed to add mfd devices to core.
viperboard: probe of 1-2.4:1.0 failed with error -17
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

rtsx_pci_power_off() is called only from rtsx_pci_suspend(), which isn't
built when PM is disabled.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

The least significat byte of the GPIO value read register
on the STMPE24xx series is on addres 0xA4 not 0xA5. Correct
against datasheet and tested on the STMPE2401 hardware.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

Linux 3.18-rc4

Black screen, screen corruption, hardware state corruption fixes.

* tag 'drm-intel-fixes-2014-11-07' of git://anongit.freedesktop.org/drm-intel:
  drm/i915: safeguard against too high minimum brightness
  drm/i915: vlv: fix gunit HW state corruption during S4 suspend
  drm/i915: Disable caches for Global GTT.