Pull zstd support from Chris Mason:
 "Nick Terrell's patch series to add zstd support to the kernel has been
  floating around for a while. After talking with Dave Sterba, Herbert
  and Phillip, we decided to send the whole thing in as one pull
  request.

  zstd is a big win in speed over zlib and in compression ratio over
  lzo, and the compression team here at FB has gotten great results
  using it in production. Nick will continue to update the kernel side
  with new improvements from the open source zstd userland code.

  Nick has a number of benchmarks for the main zstd code in his lib/zstd
  commit:

      I ran the benchmarks on a Ubuntu 14.04 VM with 2 cores and 4 GiB
      of RAM. The VM is running on a MacBook Pro with a 3.1 GHz Intel
      Core i7 processor, 16 GB of RAM, and a SSD. I benchmarked using
      `silesia.tar` [3], which is 211,988,480 B large. Run the following
      commands for the benchmark:

        sudo modprobe zstd_compress_test
        sudo mknod zstd_compress_test c 245 0
        sudo cp silesia.tar zstd_compress_test

      The time is reported by the time of the userland `cp`.
      The MB/s is computed with

        1,536,217,008 B / time(buffer size, hash)

      which includes the time to copy from userland.
      The Adjusted MB/s is computed with

        1,536,217,088 B / (time(buffer size, hash) - time(buffer size, none)).

      The memory reported is the amount of memory the compressor
      requests.

        | Method   | Size (B) | Time (s) | Ratio | MB/s    | Adj MB/s | Mem (MB) |
        |----------|----------|----------|-------|---------|----------|----------|
        | none     | 11988480 |    0.100 |     1 | 2119.88 |        - |        - |
        | zstd -1  | 73645762 |    1.044 | 2.878 |  203.05 |   224.56 |     1.23 |
        | zstd -3  | 66988878 |    1.761 | 3.165 |  120.38 |   127.63 |     2.47 |
        | zstd -5  | 65001259 |    2.563 | 3.261 |   82.71 |    86.07 |     2.86 |
        | zstd -10 | 60165346 |   13.242 | 3.523 |   16.01 |    16.13 |    13.22 |
        | zstd -15 | 58009756 |   47.601 | 3.654 |    4.45 |     4.46 |    21.61 |
        | zstd -19 | 54014593 |  102.835 | 3.925 |    2.06 |     2.06 |    60.15 |
        | zlib -1  | 77260026 |    2.895 | 2.744 |   73.23 |    75.85 |     0.27 |
        | zlib -3  | 72972206 |    4.116 | 2.905 |   51.50 |    52.79 |     0.27 |
        | zlib -6  | 68190360 |    9.633 | 3.109 |   22.01 |    22.24 |     0.27 |
        | zlib -9  | 67613382 |   22.554 | 3.135 |    9.40 |     9.44 |     0.27 |

      I benchmarked zstd decompression using the same method on the same
      machine. The benchmark file is located in the upstream zstd repo
      under `contrib/linux-kernel/zstd_decompress_test.c` [4]. The
      memory reported is the amount of memory required to decompress
      data compressed with the given compression level. If you know the
      maximum size of your input, you can reduce the memory usage of
      decompression irrespective of the compression level.

        | Method   | Time (s) | MB/s    | Adjusted MB/s | Memory (MB) |
        |----------|----------|---------|---------------|-------------|
        | none     |    0.025 | 8479.54 |             - |           - |
        | zstd -1  |    0.358 |  592.15 |        636.60 |        0.84 |
        | zstd -3  |    0.396 |  535.32 |        571.40 |        1.46 |
        | zstd -5  |    0.396 |  535.32 |        571.40 |        1.46 |
        | zstd -10 |    0.374 |  566.81 |        607.42 |        2.51 |
        | zstd -15 |    0.379 |  559.34 |        598.84 |        4.61 |
        | zstd -19 |    0.412 |  514.54 |        547.77 |        8.80 |
        | zlib -1  |    0.940 |  225.52 |        231.68 |        0.04 |
        | zlib -3  |    0.883 |  240.08 |        247.07 |        0.04 |
        | zlib -6  |    0.844 |  251.17 |        258.84 |        0.04 |
        | zlib -9  |    0.837 |  253.27 |        287.64 |        0.04 |

  I ran a long series of tests and benchmarks on the btrfs side and the
  gains are very similar to the core benchmarks Nick ran"

* 'zstd-minimal' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  squashfs: Add zstd support
  btrfs: Add zstd support
  lib: Add zstd modules
  lib: Add xxhash module

Pull Kbuild updates from Masahiro Yamada:

 - Use Make-builtin $(abspath ...) helper to get absolute path

 - Add W=2 extra warning option to detect unused macros

 - Use more KCONFIG_CONFIG instead hard-coded .config

 - Fix bugs of tar*-pkg targets

* tag 'kbuild-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: buildtar: do not print successful message if tar returns error
  kbuild: buildtar: fix tar error when CONFIG_MODULES is disabled
  kbuild: Use KCONFIG_CONFIG in buildtar
  Kbuild: enable -Wunused-macros warning for "make W=2"
  kbuild: use $(abspath ...) instead of $(shell cd ... && /bin/pwd)

Merge tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper updates from Mike Snitzer:

 - Some request-based DM core and DM multipath fixes and cleanups

 - Constify a few variables in DM core and DM integrity

 - Add bufio optimization and checksum failure accounting to DM
   integrity

 - Fix DM integrity to avoid checking integrity of failed reads

 - Fix DM integrity to use init_completion

 - A couple DM log-writes target fixes

 - Simplify DAX flushing by eliminating the unnecessary flush
   abstraction that was stood up for DM's use.

* tag 'for-4.14/dm-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dax: remove the pmem_dax_ops->flush abstraction
  dm integrity: use init_completion instead of COMPLETION_INITIALIZER_ONSTACK
  dm integrity: make blk_integrity_profile structure const
  dm integrity: do not check integrity for failed read operations
  dm log writes: fix >512b sectorsize support
  dm log writes: don't use all the cpu while waiting to log blocks
  dm ioctl: constify ioctl lookup table
  dm: constify argument arrays
  dm integrity: count and display checksum failures
  dm integrity: optimize writing dm-bufio buffers that are partially changed
  dm rq: do not update rq partially in each ending bio
  dm rq: make dm-sq requeuing behavior consistent with dm-mq behavior
  dm mpath: complain about unsupported __multipath_map_bio() return values
  dm mpath: avoid that building with W=1 causes gcc 7 to complain about fall-through

Pull fbdev updates from Bartlomiej Zolnierkiewicz:

 - make fbcon a built-time depency for fbdev (fbcon was tristate option
   before, now it is a bool) - this is a first step in preparations for
   making console_lock usage saner (currently it acts like the BKL for
   all things fbdev/fbcon) (Daniel Vetter)

 - add fbcon=margin:<color> command line option to select the fbcon
   margin color (David Lechner)

 - add DMI quirk table for x86 systems which need fbcon rotation
   (devices like Asus T100HA, GPD Pocket, the GPD win and the I.T.Works
   TW891) (Hans de Goede)

 - fix 1bpp logo support for unusual width (needed by LEGO MINDSTORMS
   EV3) (David Lechner)

 - enable Xilinx FB driver for ARM ZynqMP platform (Michal Simek)

 - fix use after free in the error path of udlfb driver (Anton Vasilyev)

 - fix error return code handling in pxa3xx_gcu driver (Gustavo A. R.
   Silva)

 - fix bootparams.screeninfo arguments checking in vgacon (Jan H.
   Schönherr)

 - do not leak uninitialized padding in clk to userspace in the debug
   code of atyfb driver (Vladis Dronov)

 - fix compiler warnings in fbcon code and matroxfb driver (Arnd
   Bergmann)

 - convert fbdev susbsytem to using %pOF instead of full_name (Rob
   Herring)

 - structures constifications (Arvind Yadav, Bhumika Goyal, Gustavo A.
   R. Silva, Julia Lawall)

 - misc cleanups (Gustavo A. R. Silva, Hyun Kwon, Julia Lawall, Kuninori
   Morimoto, Lynn Lei)

* tag 'fbdev-v4.14' of git://github.com/bzolnier/linux: (75 commits)
  video/console: Update BIOS dates list for GPD win console rotation DMI quirk
  video/console: Add rotated LCD-panel DMI quirk for the VIOS LTH17
  video: fbdev: sis: fix duplicated code for different branches
  video: fbdev: make fb_var_screeninfo const
  video: fbdev: aty: do not leak uninitialized padding in clk to userspace
  vgacon: Prevent faulty bootparams.screeninfo from causing harm
  video: fbdev: make fb_videomode const
  video/console: Add new BIOS date for GPD pocket to dmi quirk table
  fbcon: remove restriction on margin color
  video: ARM CLCD: constify amba_id
  video: fm2fb: constify zorro_device_id
  video: fbdev: annotate fb_fix_screeninfo with const and __initconst
  omapfb: constify omap_video_timings structures
  video: fbdev: udlfb: Fix use after free on dlfb_usb_probe error path
  fbdev: i810: make fb_ops const
  fbdev: matrox: make fb_ops const
  video: fbdev: pxa3xx_gcu: fix error return code in pxa3xx_gcu_probe()
  video: fbdev: Enable Xilinx FB for ZynqMP
  video: fbdev: Fix multiple style issues in xilinxfb
  video: fbdev: udlfb: constify usb_device_id.
  ...

Pull watchdog updates from Wim Van Sebroeck:

 - add support for the watchdog on Meson8 and Meson8m2

 - add support for MediaTek MT7623 and MT7622 SoC

 - add support for the r8a77995 wdt

 - explicitly request exclusive reset control for asm9260_wdt,
   zx2967_wdt, rt2880_wdt and mt7621_wdt

 - improvements to asm9260_wdt, aspeed_wdt, renesas_wdt and cadence_wdt

 - add support for reading freq via CCF + suspend/resume support for
   of_xilinx_wdt

 - constify watchdog_ops and various device-id structures

 - revert of commit 1fccb730 ("iTCO_wdt: all versions count down
   twice") (Bug 196509)

* git://www.linux-watchdog.org/linux-watchdog: (40 commits)
  watchdog: mei_wdt: constify mei_cl_device_id
  watchdog: sp805: constify amba_id
  watchdog: ziirave: constify i2c_device_id
  watchdog: sc1200: constify pnp_device_id
  dt-bindings: watchdog: renesas-wdt: Add support for the r8a77995 wdt
  watchdog: renesas_wdt: update copyright dates
  watchdog: renesas_wdt: make 'clk' a variable local to probe()
  watchdog: renesas_wdt: consistently use RuntimePM for clock management
  watchdog: aspeed: Support configuration of external signal properties
  dt-bindings: watchdog: aspeed: External reset signal properties
  drivers/watchdog: Add optional ASPEED device tree properties
  drivers/watchdog: ASPEED reference dev tree properties for config
  watchdog: da9063_wdt: Simplify by removing unneeded struct...
  watchdog: bcm7038: Check the return value from clk_prepare_enable()
  watchdog: qcom: Check for platform_get_resource() failure
  watchdog: of_xilinx_wdt: Add suspend/resume support
  watchdog: of_xilinx_wdt: Add support for reading freq via CCF
  dt-bindings: watchdog: mediatek: add support for MediaTek MT7623 and MT7622 SoC
  watchdog: max77620_wdt: constify platform_device_id
  watchdog: pcwd_usb: constify usb_device_id
  ...

Pull dmi update from Jean Delvare:
 "Mark all struct dmi_system_id instances const"

* 'dmi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  dmi: Mark all struct dmi_system_id instances const

Pull pin control fixes from Linus Walleij:
 "This slew of fixes for pin control was noticed and patched up early,
  so to get the annoyance out of the way for -rc1 it would make sense to
  send them already.

   - Fix a build include in the Uniphier driver to keep pace with
     ongoing refactorings.

   - Fix a slew of minor semantic and syntactic issues as well as
     stricting up Kconfig for the new Spreadtrum driver.

   - Fix the GPIO interrupt set-up on the Marvell 37xx Armada as fallout
     for dynamically allocating irq descriptors from the core. (Also
     tagged for stable.)

   - Fix AMD register suspend/resume state spool/unspooling so that
     wakeup works as it should. (Also tagged for stable.)"

* tag 'pinctrl-v4.14-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl:
  pinctrl/amd: save pin registers over suspend/resume
  pinctrl: armada-37xx: Fix gpio interrupt setup
  pinctrl: sprd: fix off by one bugs
  pinctrl: sprd: check for allocation failure
  pinctrl: sprd: Restrict PINCTRL_SPRD to ARCH_SPRD or COMPILE_TEST
  pinctrl: sprd: fix build errors and dependencies
  pinctrl: sprd: make three local functions static
  pinctrl: uniphier: include <linux/build_bug.h> instead of <linux/bug.h>

Merge misc fixes from Andrew Morton:
 "A few leftovers"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  mm, page_owner: skip unnecessary stack_trace entries
  arm64: stacktrace: avoid listing stacktrace functions in stacktrace
  mm: treewide: remove GFP_TEMPORARY allocation flag
  IB/mlx4: fix sprintf format warning
  fscache: fix fscache_objlist_show format processing
  lib/test_bitmap.c: use ULL suffix for 64-bit constants
  procfs: remove unused variable
  drivers/media/cec/cec-adap.c: fix build with gcc-4.4.4
  idr: remove WARN_ON_ONCE() when trying to replace negative ID

Now that we have added breaks in the wait queue scan and allow bookmark
on scan position, we put this logic in the wake_up_page_bit function.

We can have very long page wait list in large system where multiple
pages share the same wait list. We break the wake up walk here to allow
other cpus a chance to access the list, and not to disable the interrupts
when traversing the list for too long.  This reduces the interrupt and
rescheduling latency, and excessive page wait queue lock hold time.

[ v2: Remove bookmark_wake_function ]
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We encountered workloads that have very long wake up list on large
systems. A waker takes a long time to traverse the entire wake list and
execute all the wake functions.

We saw page wait list that are up to 3700+ entries long in tests of
large 4 and 8 socket systems. It took 0.8 sec to traverse such list
during wake up. Any other CPU that contends for the list spin lock will
spin for a long time. It is a result of the numa balancing migration of
hot pages that are shared by many threads.

Multiple CPUs waking are queued up behind the lock, and the last one
queued has to wait until all CPUs did all the wakeups.

The page wait list is traversed with interrupt disabled, which caused
various problems. This was the original cause that triggered the NMI
watch dog timer in: https://patchwork.kernel.org/patch/9800303/ . Only
extending the NMI watch dog timer there helped.

This patch bookmarks the waker's scan position in wake list and break
the wake up walk, to allow access to the list before the waker resume
its walk down the rest of the wait list. It lowers the interrupt and
rescheduling latency.

This patch also provides a performance boost when combined with the next
patch to break up page wakeup list walk. We saw 22% improvement in the
will-it-scale file pread2 test on a Xeon Phi system running 256 threads.

[ v2: Merged in Linus' changes to remove the bookmark_wake_function, and
  simply access to flags. ]
Reported-by: Kan Liang <kan.liang@intel.com>
Tested-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

... and __initconst if applicable.

Based on similar work for an older kernel in the Grsecurity patch.

[JD: fix toshiba-wmi build]
[JD: add htcpen]
[JD: move __initconst where checkscript wants it]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jean Delvare <jdelvare@suse.de>

The page_owner stacktrace always begin as follows:

  [<ffffff987bfd48f4>] save_stack+0x40/0xc8
  [<ffffff987bfd4da8>] __set_page_owner+0x3c/0x6c

These two entries do not provide any useful information and limits the
available stacktrace depth.  The page_owner stacktrace was skipping
caller function from stack entries but this was missed with commit
f2ca0b55 ("mm/page_owner: use stackdepot to store stacktrace")

Example page_owner entry after the patch:

  Page allocated via order 0, mask 0x8(ffffff80085fb714)
  PFN 654411 type Movable Block 639 type CMA Flags 0x0(ffffffbe5c7f12c0)
  [<ffffff9b64989c14>] post_alloc_hook+0x70/0x80
  ...
  [<ffffff9b651216e8>] msm_comm_try_state+0x5f8/0x14f4
  [<ffffff9b6512486c>] msm_vidc_open+0x5e4/0x7d0
  [<ffffff9b65113674>] msm_v4l2_open+0xa8/0x224

Link: http://lkml.kernel.org/r/1504078343-28754-2-git-send-email-guptap@codeaurora.org
Fixes: f2ca0b55 ("mm/page_owner: use stackdepot to store stacktrace")
Signed-off-by: Prakash Gupta <guptap@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The stacktraces always begin as follows:

  [<c00117b4>] save_stack_trace_tsk+0x0/0x98
  [<c0011870>] save_stack_trace+0x24/0x28
  ...

This is because the stack trace code includes the stack frames for
itself.  This is incorrect behaviour, and also leads to "skip" doing the
wrong thing (which is the number of stack frames to avoid recording.)

Perversely, it does the right thing when passed a non-current thread.
Fix this by ensuring that we have a known constant number of frames
above the main stack trace function, and always skip these.

This was fixed for arch arm by commit 3683f44c ("ARM: stacktrace:
avoid listing stacktrace functions in stacktrace")

Link: http://lkml.kernel.org/r/1504078343-28754-1-git-send-email-guptap@codeaurora.orgSigned-off-by: Prakash Gupta <guptap@codeaurora.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

GFP_TEMPORARY was introduced by commit e12ba74d ("Group short-lived
and reclaimable kernel allocations") along with __GFP_RECLAIMABLE.  It's
primary motivation was to allow users to tell that an allocation is
short lived and so the allocator can try to place such allocations close
together and prevent long term fragmentation.  As much as this sounds
like a reasonable semantic it becomes much less clear when to use the
highlevel GFP_TEMPORARY allocation flag.  How long is temporary? Can the
context holding that memory sleep? Can it take locks? It seems there is
no good answer for those questions.

The current implementation of GFP_TEMPORARY is basically GFP_KERNEL |
__GFP_RECLAIMABLE which in itself is tricky because basically none of
the existing caller provide a way to reclaim the allocated memory.  So
this is rather misleading and hard to evaluate for any benefits.

I have checked some random users and none of them has added the flag
with a specific justification.  I suspect most of them just copied from
other existing users and others just thought it might be a good idea to
use without any measuring.  This suggests that GFP_TEMPORARY just
motivates for cargo cult usage without any reasoning.

I believe that our gfp flags are quite complex already and especially
those with highlevel semantic should be clearly defined to prevent from
confusion and abuse.  Therefore I propose dropping GFP_TEMPORARY and
replace all existing users to simply use GFP_KERNEL.  Please note that
SLAB users with shrinkers will still get __GFP_RECLAIMABLE heuristic and
so they will be placed properly for memory fragmentation prevention.

I can see reasons we might want some gfp flag to reflect shorterm
allocations but I propose starting from a clear semantic definition and
only then add users with proper justification.

This was been brought up before LSF this year by Matthew [1] and it
turned out that GFP_TEMPORARY really doesn't have a clear semantic.  It
seems to be a heuristic without any measured advantage for most (if not
all) its current users.  The follow up discussion has revealed that
opinions on what might be temporary allocation differ a lot between
developers.  So rather than trying to tweak existing users into a
semantic which they haven't expected I propose to simply remove the flag
and start from scratch if we really need a semantic for short term
allocations.

[1] http://lkml.kernel.org/r/20170118054945.GD18349@bombadil.infradead.org

[akpm@linux-foundation.org: fix typo]
[akpm@linux-foundation.org: coding-style fixes]
[sfr@canb.auug.org.au: drm/i915: fix up]
  Link: http://lkml.kernel.org/r/20170816144703.378d4f4d@canb.auug.org.au
Link: http://lkml.kernel.org/r/20170728091904.14627-1-mhocko@kernel.orgSigned-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Mel Gorman <mgorman@suse.de>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Neil Brown <neilb@suse.de>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gcc-7 points out that a negative port_num value would overflow the
string buffer:

  drivers/infiniband/hw/mlx4/sysfs.c: In function 'mlx4_ib_device_register_sysfs':
  drivers/infiniband/hw/mlx4/sysfs.c:251:16: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
  drivers/infiniband/hw/mlx4/sysfs.c:251:2: note: 'sprintf' output between 2 and 11 bytes into a destination of size 10
  drivers/infiniband/hw/mlx4/sysfs.c:303:17: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
  drivers/infiniband/hw/mlx4/sysfs.c:303:3: note: 'sprintf' output between 2 and 11 bytes into a destination of size 10

While we should be able to assume that port_num is positive here, making
the buffer one byte longer has no downsides and avoids the warning.

Fixes: c1e7e466 ("IB/mlx4: Add iov directory in sysfs under the ib device")
Link: http://lkml.kernel.org/r/20170714120720.906842-23-arnd@arndb.deSigned-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gcc points out a minor bug in the handling of unknown cookie types,
which could result in a string overflow when the integer is copied into
a 3-byte string:

  fs/fscache/object-list.c: In function 'fscache_objlist_show':
  fs/fscache/object-list.c:265:19: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
   sprintf(_type, "%02u", cookie->def->type);
                  ^~~~~~
  fs/fscache/object-list.c:265:4: note: 'sprintf' output between 3 and 4 bytes into a destination of size 3

This is currently harmless as no code sets a type other than 0 or 1, but
it makes sense to use snprintf() here to avoid overflowing the array if
that changes.

Link: http://lkml.kernel.org/r/20170714120720.906842-22-arnd@arndb.deSigned-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

With gcc 4.1.2:

  lib/test_bitmap.c:189: warning: integer constant is too large for `long' type
  lib/test_bitmap.c:190: warning: integer constant is too large for `long' type
  lib/test_bitmap.c:194: warning: integer constant is too large for `long' type
  lib/test_bitmap.c:195: warning: integer constant is too large for `long' type

Add the missing "ULL" suffix to fix this.

Link: http://lkml.kernel.org/r/1505040523-31230-1-git-send-email-geert@linux-m68k.org
Fixes: 60ef6900 ("bitmap: introduce BITMAP_FROM_U64()")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In NOMMU configurations, we get a warning about a variable that has become
unused:

  fs/proc/task_nommu.c: In function 'nommu_vma_show':
  fs/proc/task_nommu.c:148:28: error: unused variable 'priv' [-Werror=unused-variable]

Link: http://lkml.kernel.org/r/20170911200231.3171415-1-arnd@arndb.de
Fixes: 1240ea0d ("fs, proc: remove priv argument from is_stack")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

gcc-4.4.4 has issues with initialization of anonymous unions:

  drivers/media/cec/cec-adap.c: In function 'cec_queue_msg_fh':
  drivers/media/cec/cec-adap.c:184: error: unknown field 'lost_msgs' specified in initializer

work around this.

Fixes: 6b2bbb08 ("media: cec: rework the cec event handling")
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Hans Verkuil <hans.verkuil@cisco.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Cc: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

IDR only supports non-negative IDs.  There used to be a 'WARN_ON_ONCE(id <
0)' in idr_replace(), but it was intentionally removed by commit
2e1c9b28 ("idr: remove WARN_ON_ONCE() on negative IDs").

Then it was added back by commit 0a835c4f ("Reimplement IDR and IDA
using the radix tree").  However it seems that adding it back was a
mistake, given that some users such as drm_gem_handle_delete()
(DRM_IOCTL_GEM_CLOSE) pass in a value from userspace to idr_replace(),
allowing the WARN_ON_ONCE to be triggered.  drm_gem_handle_delete()
actually just wants idr_replace() to return an error code if the ID is
not allocated, including in the case where the ID is invalid (negative).

So once again remove the bogus WARN_ON_ONCE().

This bug was found by syzkaller, which encountered the following
warning:

    WARNING: CPU: 3 PID: 3008 at lib/idr.c:157 idr_replace+0x1d8/0x240 lib/idr.c:157
    Kernel panic - not syncing: panic_on_warn set ...

    CPU: 3 PID: 3008 Comm: syzkaller218828 Not tainted 4.13.0-rc4-next-20170811 #2
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    Call Trace:
     fixup_bug+0x40/0x90 arch/x86/kernel/traps.c:190
     do_trap_no_signal arch/x86/kernel/traps.c:224 [inline]
     do_trap+0x260/0x390 arch/x86/kernel/traps.c:273
     do_error_trap+0x120/0x390 arch/x86/kernel/traps.c:310
     do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:323
     invalid_op+0x1e/0x30 arch/x86/entry/entry_64.S:930
    RIP: 0010:idr_replace+0x1d8/0x240 lib/idr.c:157
    RSP: 0018:ffff8800394bf9f8 EFLAGS: 00010297
    RAX: ffff88003c6c60c0 RBX: 1ffff10007297f43 RCX: 0000000000000000
    RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8800394bfa78
    RBP: ffff8800394bfae0 R08: ffffffff82856487 R09: 0000000000000000
    R10: ffff8800394bf9a8 R11: ffff88006c8bae28 R12: ffffffffffffffff
    R13: ffff8800394bfab8 R14: dffffc0000000000 R15: ffff8800394bfbc8
     drm_gem_handle_delete+0x33/0xa0 drivers/gpu/drm/drm_gem.c:297
     drm_gem_close_ioctl+0xa1/0xe0 drivers/gpu/drm/drm_gem.c:671
     drm_ioctl_kernel+0x1e7/0x2e0 drivers/gpu/drm/drm_ioctl.c:729
     drm_ioctl+0x72e/0xa50 drivers/gpu/drm/drm_ioctl.c:825
     vfs_ioctl fs/ioctl.c:45 [inline]
     do_vfs_ioctl+0x1b1/0x1520 fs/ioctl.c:685
     SYSC_ioctl fs/ioctl.c:700 [inline]
     SyS_ioctl+0x8f/0xc0 fs/ioctl.c:691
     entry_SYSCALL_64_fastpath+0x1f/0xbe

Here is a C reproducer:

    #include <fcntl.h>
    #include <stddef.h>
    #include <stdint.h>
    #include <sys/ioctl.h>
    #include <drm/drm.h>

    int main(void)
    {
            int cardfd = open("/dev/dri/card0", O_RDONLY);

            ioctl(cardfd, DRM_IOCTL_GEM_CLOSE,
                  &(struct drm_gem_close) { .handle = -1 } );
    }

Link: http://lkml.kernel.org/r/20170906235306.20534-1-ebiggers3@gmail.com
Fixes: 0a835c4f ("Reimplement IDR and IDA using the radix tree")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Matthew Wilcox <mawilcox@microsoft.com>
Cc: <stable@vger.kernel.org> [v4.11+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull perf fixes from Ingo Molnar:
 "A handful of tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf stat: Wait for the correct child
  perf tools: Support running perf binaries with a dash in their name
  perf config: Check not only section->from_system_config but also item's
  perf ui progress: Fix progress update
  perf ui progress: Make sure we always define step value
  perf tools: Open perf.data with O_CLOEXEC flag
  tools lib api: Fix make DEBUG=1 build
  perf tests: Fix compile when libunwind's unwind.h is available
  tools include linux: Guard against redefinition of some macros

Pull scheduler fixes from Ingo Molnar:
 "Three CPU hotplug related fixes and a debugging improvement"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/debug: Add debugfs knob for "sched_debug"
  sched/core: WARN() when migrating to an offline CPU
  sched/fair: Plug hole between hotplug and active_load_balance()
  sched/fair: Avoid newidle balance for !active CPUs

Pull x86 fixes from Ingo Molnar:
 "The main changes are the PCID fixes from Andy, but there's also two
  hyperv fixes and two paravirt updates"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/hyper-v: Remove duplicated HV_X64_EX_PROCESSOR_MASKS_RECOMMENDED definition
  x86/hyper-V: Allocate the IDT entry early in boot
  paravirt: Switch maintainer
  x86/paravirt: Remove no longer used paravirt functions
  x86/mm/64: Initialize CR4.PCIDE early
  x86/hibernate/64: Mask off CR3's PCID bits in the saved CR3
  x86/mm: Get rid of VM_BUG_ON in switch_tlb_irqs_off()

Pull OpenRISC fixlet from Stafford Horne:
 "Fix warning for upcoming work to remove linux/vmalloc.h from
  asm-generic/io.h"

* tag 'openrisc-for-linus' of git://github.com/openrisc/linux:
  openrisc: add forward declaration for struct vm_area_struct

Pull modules updates from Jessica Yu:
 "Summary of modules changes for the 4.14 merge window:

   - minor code cleanups and fixes

   - modpost: avoid building modules that have names that exceed the
     size of the name field in struct module"

* tag 'modules-for-v4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
  module: Remove const attribute from alias for MODULE_DEVICE_TABLE
  module: fix ddebug_remove_module()
  modpost: abort if module name is too long

Another merge window, another MAINTAINERS file disaster.

People have serious problems with the alphabet and sorting, and poor
Jérôme Glisse and Radim Krčmář get their names mangled by locale issues,
turning them into some mangled mess (probably others do too, but those
two stood out when sorting things again).

And we now have two copies of the same 'AS3645A LED FLASH CONTROLLER
DRIVER' in the tree and in the MAINTAINERS file, but that's a separate
issue - the duplication is real, and I left them as two entries for the
same name.

This does not try to sort the actual section pattern entries, although I
may end up doing that later.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull clk updates from Stephen Boyd:
 "The diff is dominated by the Allwinner A10/A20 SoCs getting converted
  to the sunxi-ng framework. Otherwise, the heavy hitters are various
  drivers for SoCs like AT91, Amlogic, Renesas, and Rockchip. There are
  some other new clk drivers in here too but overall this is just a
  bunch of clk drivers for various different pieces of hardware and a
  collection of non-critical fixes for clk drivers.

  New Drivers:
   - Allwinner R40 SoCs
   - Renesas R-Car Gen3 USB 2.0 clock selector PHY
   - Atmel AT91 audio PLL
   - Uniphier PXs3 SoCs
   - ARC HSDK Board PLLs
   - AXS10X Board PLLs
   - STMicroelectronics STM32H743 SoCs

  Removed Drivers:
   - Non-compiling mb86s7x support

  Updates:
   - Allwinner A10/A20 SoCs converted to sunxi-ng framework
   - Allwinner H3 CPU clk fixes
   - Renesas R-Car D3 SoC
   - Renesas V2H and M3-W modules
   - Samsung Exynos5420/5422/5800 audio fixes
   - Rockchip fractional clk approximation fixes
   - Rockchip rk3126 SoC support within the rk3128 driver
   - Amlogic gxbb CEC32 and sd_emmc clks
   - Amlogic meson8b reset controller support
   - IDT VersaClock 5P49V5925/5P49V6901 support
   - Qualcomm MSM8996 SMMU clks
   - Various 'const' applications for struct clk_ops
   - si5351 PLL reset bugfix
   - Uniphier audio on LD11/LD20 and ethernet support on LD11/LD20/Pro4/PXs2
   - Assorted Tegra clk driver fixes"

* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (120 commits)
  clk: si5351: fix PLL reset
  ASoC: atmel-classd: remove aclk clock
  ASoC: atmel-classd: remove aclk clock from DT binding
  clk: at91: clk-generated: make gclk determine audio_pll rate
  clk: at91: clk-generated: create function to find best_diff
  clk: at91: add audio pll clock drivers
  dt-bindings: clk: at91: add audio plls to the compatible list
  clk: at91: clk-generated: remove useless divisor loop
  clk: mb86s7x: Drop non-building driver
  clk: ti: check for null return in strrchr to avoid null dereferencing
  clk: Don't write error code into divider register
  clk: uniphier: add video input subsystem clock
  clk: uniphier: add audio system clock
  clk: stm32h7: Add stm32h743 clock driver
  clk: gate: expose clk_gate_ops::is_enabled
  clk: nxp: clk-lpc32xx: rename clk_gate_is_enabled()
  clk: uniphier: add PXs3 clock data
  clk: hi6220: change watchdog clock source
  clk: Kconfig: Name RK805 in Kconfig for COMMON_CLK_RK808
  clk: cs2000: Add cs2000_set_saved_rate
  ...

Pull RTC updates from Alexandre Belloni:
 "Subsystem:
   - remove .open() and .release() RTC ops
   - constify i2c_device_id

  New driver:
   - Realtek RTD1295
   - Android emulator (goldfish) RTC

  Drivers:
   - ds1307: Beginning of a huge cleanup
   - s35390a: handle invalid RTC time
   - sun6i: external oscillator gate support"

* tag 'rtc-4.14' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (40 commits)
  rtc: ds1307: use octal permissions
  rtc: ds1307: fix braces
  rtc: ds1307: fix alignments and blank lines
  rtc: ds1307: use BIT
  rtc: ds1307: use u32
  rtc: ds1307: use sizeof
  rtc: ds1307: remove regs member
  rtc: Add Realtek RTD1295
  dt-bindings: rtc: Add Realtek RTD1295
  rtc: sun6i: Add support for the external oscillator gate
  rtc: goldfish: Add RTC driver for Android emulator
  dt-bindings: Add device tree binding for Goldfish RTC driver
  rtc: ds1307: add basic support for ds1341 chip
  rtc: ds1307: remove member nvram_offset from struct ds1307
  rtc: ds1307: factor out offset to struct chip_desc
  rtc: ds1307: factor out rtc_ops to struct chip_desc
  rtc: ds1307: factor out irq_handler to struct chip_desc
  rtc: ds1307: improve irq setup
  rtc: ds1307: constify struct chip_desc variables
  rtc: ds1307: improve trickle charger initialization
  ...

Pull sound fixes from Takashi Iwai:
 "Most of the commits are trivial cleanup patches, while one commit is a
  significant fix for the race at ALSA sequencer that was spotted by
  syzkaller"

* tag 'sound-fix-4.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: seq: Cancel pending autoload work at unbinding device
  ALSA: firewire: Use common error handling code in snd_motu_stream_start_duplex()
  ALSA: asihpi: Kill BUG_ON() usages
  ALSA: core: Use %pS printk format for direct addresses
  ALSA: ymfpci: Use common error handling code in snd_ymfpci_create()
  ALSA: ymfpci: Use common error handling code in snd_card_ymfpci_probe()
  ALSA: 6fire: Use common error handling code in usb6fire_chip_probe()
  ALSA: usx2y: Use common error handling code in submit_urbs()
  ALSA: us122l: Use common error handling code in us122l_create_card()
  ALSA: hdspm: Use common error handling code in snd_hdspm_probe()
  ALSA: rme9652: Use common code in hdsp_get_iobox_version()
  ALSA: maestro3: Use common error handling code in two functions

Pull SCSI fixes from James Bottomley:
 "A tiny update: one patch corrects a Kconfig problem with the shift of
  the SAS SMP code to BSG and the other removes a vestige of user space
  target mode"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: scsi_transport_sas: select BLK_DEV_BSGLIB
  scsi: Remove Scsi_Host.uspace_req_q

Pull block fixes from Jens Axboe:
 "Small collection of fixes that would be nice to have in -rc1. This
  contains:

   - NVMe pull request form Christoph, mostly with fixes for nvme-pci,
     host memory buffer in particular.

   - Error handling fixup for cgwb_create(), in case allocation of 'wb'
     fails. From Christophe Jaillet.

   - Ensure that trace_block_getrq() gets the 'dev' in an appropriate
     fashion, to avoid a potential NULL deref. From Greg Thelen.

   - Regression fix for dm-mq with blk-mq, fixing a problem with
     stacking IO schedulers. From me.

   - string.h fixup, fixing an issue with memcpy_and_pad(). This
     original change came in through an NVMe dependency, which is why
     I'm including it here. From Martin Wilck.

   - Fix potential int overflow in __blkdev_sectors_to_bio_pages(), from
     Mikulas.

   - MBR enable fix for sed-opal, from Scott"

* 'for-linus' of git://git.kernel.dk/linux-block:
  block: directly insert blk-mq request from blk_insert_cloned_request()
  mm/backing-dev.c: fix an error handling path in 'cgwb_create()'
  string.h: un-fortify memcpy_and_pad
  nvme-pci: implement the HMB entry number and size limitations
  nvme-pci: propagate (some) errors from host memory buffer setup
  nvme-pci: use appropriate initial chunk size for HMB allocation
  nvme-pci: fix host memory buffer allocation fallback
  nvme: fix lightnvm check
  block: fix integer overflow in __blkdev_sectors_to_bio_pages()
  block: sed-opal: Set MBRDone on S3 resume path if TPER is MBREnabled
  block: tolerate tracing of NULL bio

Pull documentation fixes from Jonathan Corbet:
 "A cleanup from Mauro that needed to wait for the media pull, plus a
  handful of other fixes that wandered in"

* tag 'docs-4.14' of git://git.lwn.net/linux:
  kokr/memory-barriers.txt: Apply atomic_t.txt change
  kokr/doc: Update memory-barriers.txt for read-to-write dependencies
  docs-rst: don't require adjustbox anymore
  docs-rst: conf.py: only setup notice box colors if Sphinx < 1.6
  docs-rst: conf.py: remove lscape from LaTeX preamble

Pull fuse updates from Miklos Szeredi:
 "This fixes a regression (spotted by the Sandstorm.io folks) in the pid
  namespace handling introduced in 4.12.

  There's also a fix for honoring sync/dsync flags for pwritev2()"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: getattr cleanup
  fuse: honor iocb sync flags on write
  fuse: allow server to run in different pid_ns

Pull overlayfs updates from Miklos Szeredi:
 "This fixes d_ino correctness in readdir, which brings overlayfs on par
  with normal filesystems regarding inode number semantics, as long as
  all layers are on the same filesystem.

  There are also some bug fixes, one in particular (random ioctl's
  shouldn't be able to modify lower layers) that touches some vfs code,
  but of course no-op for non-overlay fs"

* 'overlayfs-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  ovl: fix false positive ESTALE on lookup
  ovl: don't allow writing ioctl on lower layer
  ovl: fix relatime for directories
  vfs: add flags to d_real()
  ovl: cleanup d_real for negative
  ovl: constant d_ino for non-merge dirs
  ovl: constant d_ino across copy up
  ovl: fix readdir error value
  ovl: check snprintf return

Commits:

  7dcf90e9 ("PCI: hv: Use vPCI protocol version 1.2")
  628f54cc ("x86/hyper-v: Support extended CPU ranges for TLB flush hypercalls")

added the same definition and they came in through different trees.
Fix the duplication.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephen Hemminger <sthemmin@microsoft.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: devel@linuxdriverproject.org
Link: http://lkml.kernel.org/r/20170911150620.3998-1-vkuznets@redhat.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Allocate the hypervisor callback IDT entry early in the boot sequence.

The previous code would allocate the entry as part of registering the handler
when the vmbus driver loaded, and this caused a problem for the IDT cleanup
that Thomas is working on for v4.15.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: apw@canonical.com
Cc: devel@linuxdriverproject.org
Cc: gregkh@linuxfoundation.org
Cc: jasowang@redhat.com
Cc: olaf@aepfle.de
Link: http://lkml.kernel.org/r/20170908231557.2419-1-kys@exchange.microsoft.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

Jeremy Fitzhardinge is stepping down as a paravirt maintainer. I'll
replace him.

While at it, update the file list to the actual pattern.
Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: chrisw@sous-sol.org
Cc: jeremy@goop.org
Cc: rusty@rustcorp.com.au
Cc: virtualization@lists.linux-foundation.org
Link: http://lkml.kernel.org/r/20170905143407.9227-1-jgross@suse.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

With removal of lguest some of the paravirt functions are no longer
needed:

	->read_cr4()
	->store_idt()
	->set_pmd_at()
	->set_pud_at()
	->pte_update()

Remove them.
Signed-off-by: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akataria@vmware.com
Cc: boris.ostrovsky@oracle.com
Cc: chrisw@sous-sol.org
Cc: jeremy@goop.org
Cc: rusty@rustcorp.com.au
Cc: virtualization@lists.linux-foundation.org
Cc: xen-devel@lists.xenproject.org
Link: http://lkml.kernel.org/r/20170904102527.25409-1-jgross@suse.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

cpu_init() is weird: it's called rather late (after early
identification and after most MMU state is initialized) on the boot
CPU but is called extremely early (before identification) on secondary
CPUs.  It's called just late enough on the boot CPU that its CR4 value
isn't propagated to mmu_cr4_features.

Even if we put CR4.PCIDE into mmu_cr4_features, we'd hit two
problems.  First, we'd crash in the trampoline code.  That's
fixable, and I tried that.  It turns out that mmu_cr4_features is
totally ignored by secondary_start_64(), though, so even with the
trampoline code fixed, it wouldn't help.

This means that we don't currently have CR4.PCIDE reliably initialized
before we start playing with cpu_tlbstate.  This is very fragile and
tends to cause boot failures if I make even small changes to the TLB
handling code.

Make it more robust: initialize CR4.PCIDE earlier on the boot CPU
and propagate it to secondary CPUs in start_secondary().

( Yes, this is ugly.  I think we should have improved mmu_cr4_features
  to actually control CR4 during secondary bootup, but that would be
  fairly intrusive at this stage. )
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Reported-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Tested-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Fixes: 660da7c9 ("x86/mm: Enable CR4.PCIDE on supported systems")
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Jiri reported a resume-from-hibernation failure triggered by PCID.
The root cause appears to be rather odd.  The hibernation asm
restores a CR3 value that comes from the image header.  If the image
kernel has PCID on, it's entirely reasonable for this CR3 value to
have one of the low 12 bits set.  The restore code restores it with
CR4.PCIDE=0, which means that those low 12 bits are accepted by the
CPU but are either ignored or interpreted as a caching mode.  This
is odd, but still works.  We blow up later when the image kernel
restores CR4, though, since changing CR4.PCIDE with CR3[11:0] != 0
is illegal.  Boom!

FWIW, it's entirely unclear to me what's supposed to happen if a PAE
kernel restores a non-PAE image or vice versa.  Ditto for LA57.
Reported-by: Jiri Kosina <jikos@kernel.org>
Tested-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bpetkov@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 660da7c9 ("x86/mm: Enable CR4.PCIDE on supported systems")
Link: http://lkml.kernel.org/r/18ca57090651a6341e97083883f9e814c4f14684.1504847163.git.luto@kernel.orgSigned-off-by: Ingo Molnar <mingo@kernel.org>