Just when I had decided that flush_cache_range() was always called with
a valid context, Helge reported two cases where the
"BUG_ON(!vma->vm_mm->context);" was hit on the phantom buildd:

 kernel BUG at /mnt/sdb6/linux/linux-4.15.4/arch/parisc/kernel/cache.c:587!
 CPU: 1 PID: 3254 Comm: kworker/1:2 Tainted: G D 4.15.0-1-parisc64-smp #1 Debian 4.15.4-1+b1
 Workqueue: events free_ioctx
  IAOQ[0]: flush_cache_range+0x164/0x168
  IAOQ[1]: flush_cache_page+0x0/0x1c8
  RP(r2): unmap_page_range+0xae8/0xb88
 Backtrace:
  [<00000000404a6980>] unmap_page_range+0xae8/0xb88
  [<00000000404a6ae0>] unmap_single_vma+0xc0/0x188
  [<00000000404a6cdc>] zap_page_range_single+0x134/0x1f8
  [<00000000404a702c>] unmap_mapping_range+0x1cc/0x208
  [<0000000040461518>] truncate_pagecache+0x98/0x108
  [<0000000040461624>] truncate_setsize+0x9c/0xb8
  [<00000000405d7f30>] put_aio_ring_file+0x80/0x100
  [<00000000405d803c>] aio_free_ring+0x8c/0x290
  [<00000000405d82c0>] free_ioctx+0x80/0x180
  [<0000000040284e6c>] process_one_work+0x21c/0x668
  [<00000000402854c4>] worker_thread+0x20c/0x778
  [<0000000040291d44>] kthread+0x2d4/0x2e0
  [<0000000040204020>] end_fault_vector+0x20/0xc0

This indicates that we need to handle the no context case in
flush_cache_range() as we do in flush_cache_mm().

In thinking about this, I realized that we don't need to flush the TLB
when there is no context.  So, I added context checks to the large flush
cases in flush_cache_mm() and flush_cache_range().  The large flush case
occurs frequently in flush_cache_mm() and the change should improve fork
performance.

The v2 version of this change removes the BUG_ON from flush_cache_page()
by skipping the TLB flush when there is no context.  I also added code
to flush the TLB in flush_cache_mm() and flush_cache_range() when we
have a context that's not current.  Now all three routines handle TLB
flushes in a similar manner.
Signed-off-by: John David Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org # 4.9+
Signed-off-by: Helge Deller <deller@gmx.de>

Pull btrfs fixes from David Sterba:
 "There's an important revert in this pull request that needs to go to
  stable as it causes a corruption on big endian machines.

  The other fix is for FIEMAP incorrectly reporting shared extents
  before a sync and one fix for a crash in raid56.

  So far we got only one report about the BE corruption, the stable
  kernels were out for like a week, so hopefully the scope of the damage
  is low"

* tag 'for-4.16-rc5-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  Revert "btrfs: use proper endianness accessors for super_copy"
  btrfs: add missing initialization in btrfs_check_shared
  btrfs: Fix NULL pointer exception in find_bio_stripe

Pull microblaze fixes from Michal Simek:

 - Use NO_BOOTMEM to fix boot issue

 - Fix opt lib endian dependencies

* tag 'microblaze-4.16-rc6' of git://git.monstr.eu/linux-2.6-microblaze:
  microblaze: switch to NO_BOOTMEM
  microblaze: remove unused alloc_maybe_bootmem
  microblaze: Setup dependencies for ASM optimized lib functions

Pull drm fixes from Dave Airlie:
 "i915, amd and nouveau fixes.

  i915:
   - backlight fix for some panels
   - pm fix
   - fencing fix
   - some GVT fixes

  amdgpu:
   - backlight fix across suspend/resume
   - object destruction ordering issue fix
   - displayport fix

  nouveau:
   - two backlight fixes
   - fix for some lockups

  Pretty quiet week, seems like everyone was fixing backlights"

* tag 'drm-fixes-for-v4.16-rc6' of git://people.freedesktop.org/~airlied/linux:
  drm/nouveau/bl: fix backlight regression
  drm/nouveau/bl: Fix oops on driver unbind
  drm/nouveau/mmu: ALIGN_DOWN correct variable
  drm/i915/gvt: fix user copy warning by whitelist workload rb_tail field
  drm/i915/gvt: Correct the privilege shadow batch buffer address
  drm/amdgpu/dce: Don't turn off DP sink when disconnected
  drm/amdgpu: save/restore backlight level in legacy dce code
  drm/radeon: fix prime teardown order
  drm/amdgpu: fix prime teardown order
  drm/i915: Kick the rps worker when changing the boost frequency
  drm/i915: Only prune fences after wait-for-all
  drm/i915: Enable VBT based BL control for DP
  drm/i915/gvt: keep oa config in shadow ctx
  drm/i915/gvt: Add runtime_pm_get/put into gvt_switch_mmio

This reverts commit 3c181c12.

The offending patch was merged in 4.16-rc4 and was promptly applied to
stable kernels 4.14.25 and 4.15.8.

The patch causes a corruption in several superblock items on big-endian
machines because of messed up endianity conversions. The damage is
manually repairable. A filesystem cannot be mounted again after it has
been unmounted once.

We do a full revert and not a fixup so stable can pick that patch ASAP.

Fixes: 3c181c12 ("btrfs: use proper endianness accessors for super_copy")
Link: https://lkml.kernel.org/r/1521139304@msgid.manchmal.in-ulm.de
CC: stable@vger.kernel.org # 4.14+
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Signed-off-by: David Sterba <dsterba@suse.com>

Microblaze doesn't set CONFIG_NO_BOOTMEM and so memblock_virt_alloc()
doesn't work for CONFIG_HAVE_MEMBLOCK && !CONFIG_NO_BOOTMEM.

Similar change was already done by others architectures
"ARM: mm: Remove bootmem code and switch to NO_BOOTMEM"
(sha1: 84f452b1)
or
"openrisc: Consolidate setup to use memblock instead of bootmem"
(sha1: 266c7fad)
or
"parisc: Drop bootmem and switch to memblock"
(sha1: 4fe9e1d9)
or
"powerpc: Remove bootmem allocator"
(sha1: 10239733)
or
"s390/mm: Convert bootmem to memblock"
(sha1: 50be6345)
or
"sparc64: Convert over to NO_BOOTMEM."
(sha1: 625d693e)
or
"xtensa: drop sysmem and switch to memblock"
(sha1: 0e46c111)

Issue was introduced by:
"of/fdt: use memblock_virt_alloc for early alloc"
(sha1: 0fa1c579)
Signed-off-by: Rob Herring <robh@kernel.org>
Tested-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

alloc_maybe_bootmem is unused, so remove it.
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

The patch:
"microblaze: Setup proper dependency for optimized lib functions"
(sha1: 7b6ce52b)
didn't setup all dependencies properly.
Optimized lib functions in C are also present for little endian
and optimized library functions in assembler are implemented only for
big endian version.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

Merge tag 'drm-intel-fixes-2018-03-15' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

Only GVT fixes:
- Two warnings fix for runtime pm and usr copy (Xiong, Zhenyu)
- OA context fix for vGPU profiling (Min)
- privilege batch buffer reloc fix (Fred)

* tag 'drm-intel-fixes-2018-03-15' of git://anongit.freedesktop.org/drm/drm-intel:
  drm/i915/gvt: fix user copy warning by whitelist workload rb_tail field
  drm/i915/gvt: Correct the privilege shadow batch buffer address
  drm/i915/gvt: keep oa config in shadow ctx
  drm/i915/gvt: Add runtime_pm_get/put into gvt_switch_mmio

nouveau regression fixes.

* 'linux-4.16' of git://github.com/skeggsb/linux:
  drm/nouveau/bl: fix backlight regression
  drm/nouveau/bl: Fix oops on driver unbind
  drm/nouveau/mmu: ALIGN_DOWN correct variable

Pull vfs fixes from Al Viro:

 - backport-friendly part of lock_parent() race fix

 - a fix for an assumption in the heurisic used by path_connected() that
   is not true on NFS

 - livelock fixes for d_alloc_parallel()

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Teach path_connected to handle nfs filesystems with multiple roots.
  fs: dcache: Use READ_ONCE when accessing i_dir_seq
  fs: dcache: Avoid livelock between d_alloc_parallel and __d_add
  lock_parent() needs to recheck if dentry got __dentry_kill'ed under it

Fixes: 3c66c87d ("drm/nouveau/disp: remove hw-specific customisation
of output paths")
Suggested-by: Ben Skeggs <skeggsb@redhat.com>
Signed-off-by: Karol Herbst <kherbst@redhat.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Unbinding nouveau on a dual GPU MacBook Pro oopses because we iterate
over the bl_connectors list in nouveau_backlight_exit() but skipped
initializing it in nouveau_backlight_init().  Stacktrace for posterity:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000010
    IP: nouveau_backlight_exit+0x2b/0x70 [nouveau]
    nouveau_display_destroy+0x29/0x80 [nouveau]
    nouveau_drm_unload+0x65/0xe0 [nouveau]
    drm_dev_unregister+0x3c/0xe0 [drm]
    drm_put_dev+0x2e/0x60 [drm]
    nouveau_drm_device_remove+0x47/0x70 [nouveau]
    pci_device_remove+0x36/0xb0
    device_release_driver_internal+0x157/0x220
    driver_detach+0x39/0x70
    bus_remove_driver+0x51/0xd0
    pci_unregister_driver+0x2a/0xa0
    nouveau_drm_exit+0x15/0xfb0 [nouveau]
    SyS_delete_module+0x18c/0x290
    system_call_fast_compare_end+0xc/0x6f

Fixes: b53ac1ee ("drm/nouveau/bl: Do not register interface if Apple GMUX detected")
Cc: stable@vger.kernel.org # v4.10+
Cc: Pierre Moreau <pierre.morrow@free.fr>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

Commit 7110c89bb8852ff8b0f88ce05b332b3fe22bd11e ("mmu: swap out round
for ALIGN") replaced two calls to round/rounddown with ALIGN/ALIGN_DOWN,
but erroneously applied ALIGN_DOWN to a different variable (addr) and left
intended variable (tail) not rounded/ALIGNed.

As a result screen corruption, X lockups are observable. An example of kernel
log of affected system with NV98 card where it was bisected:

nouveau 0000:01:00.0: gr: TRAP_M2MF 00000002 [IN]
nouveau 0000:01:00.0: gr: TRAP_M2MF 00320951 400007c0 00000000 04000000
nouveau 0000:01:00.0: gr: 00200000 [] ch 1 [000fbbe000 DRM] subc 4 class 5039
mthd 0100 data 00000000
nouveau 0000:01:00.0: fb: trapped read at 0040000000 on channel 1
[0fbbe000 DRM]
engine 00 [PGRAPH] client 03 [DISPATCH] subclient 04 [M2M_IN] reason 00000006
[NULL_DMAOBJ]

Fixes bug 105173 ("[MCP79][Regression] Unhandled NULL pointer dereference in
nvkm_object_unmap since kernel 4.15")
https://bugs.freedesktop.org/show_bug.cgi?id=105173

Fixes: 7110c89bb885 ("mmu: swap out round for ALIGN ")
Tested-by: Pierre Moreau <pierre.morrow@free.fr>
Reviewed-by: Pierre Moreau <pierre.morrow@free.fr>
Signed-off-by: Maris Nartiss <maris.nartiss@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Cc: stable@vger.kernel.org # v4.15+

On nfsv2 and nfsv3 the nfs server can export subsets of the same
filesystem and report the same filesystem identifier, so that the nfs
client can know they are the same filesystem.  The subsets can be from
disjoint directory trees.  The nfsv2 and nfsv3 filesystems provides no
way to find the common root of all directory trees exported form the
server with the same filesystem identifier.

The practical result is that in struct super s_root for nfs s_root is
not necessarily the root of the filesystem.  The nfs mount code sets
s_root to the root of the first subset of the nfs filesystem that the
kernel mounts.

This effects the dcache invalidation code in generic_shutdown_super
currently called shrunk_dcache_for_umount and that code for years
has gone through an additional list of dentries that might be dentry
trees that need to be freed to accomodate nfs.

When I wrote path_connected I did not realize nfs was so special, and
it's hueristic for avoiding calling is_subdir can fail.

The practical case where this fails is when there is a move of a
directory from the subtree exposed by one nfs mount to the subtree
exposed by another nfs mount.  This move can happen either locally or
remotely.  With the remote case requiring that the move directory be cached
before the move and that after the move someone walks the path
to where the move directory now exists and in so doing causes the
already cached directory to be moved in the dcache through the magic
of d_splice_alias.

If someone whose working directory is in the move directory or a
subdirectory and now starts calling .. from the initial mount of nfs
(where s_root == mnt_root), then path_connected as a heuristic will
not bother with the is_subdir check.  As s_root really is not the root
of the nfs filesystem this heuristic is wrong, and the path may
actually not be connected and path_connected can fail.

The is_subdir function might be cheap enough that we can call it
unconditionally.  Verifying that will take some benchmarking and
the result may not be the same on all kernels this fix needs
to be backported to.  So I am avoiding that for now.

Filesystems with snapshots such as nilfs and btrfs do something
similar.  But as the directory tree of the snapshots are disjoint
from one another and from the main directory tree rename won't move
things between them and this problem will not occur.

Cc: stable@vger.kernel.org
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Fixes: 397d425d ("vfs: Test for and handle paths that are unreachable from their mnt_root")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

gvt-fixes-2018-03-15

- Two warnings fix for runtime pm and usr copy (Xiong, Zhenyu)
- OA context fix for vGPU profiling (Min)
- privilege batch buffer reloc fix (Fred)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180315100023.5n5a74afky6qinoh@zhen-hp.sh.intel.com

pmdp_invalidate() was changed to update the pmd atomically
(to not lose dirty/access bits) and return the original pmd
value.

However, in doing so, we lost a lot of the essential work that
set_pmd_at() does, namely to update hugepage mapping counts and
queuing up the batched TLB flush entry.

Thus we were not flushing entries out of the TLB when making
such PMD changes.

Fix this by abstracting the accounting work of set_pmd_at() out into a
separate function, and call it from pmdp_establish().

Fixes: a8e654f0 ("sparc64: update pmdp_invalidate() to return old pmd value")
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull sound fixes from Takashi Iwai:
 "A series of small fixes in ASoC, HD-audio and core stuff:

   - a UAF fix in ALSA PCM core

   - yet more hardening for ALSA sequencer

   - a regression fix for the previous HD-audio power_save option change

   - various ASoC codec fixes (sgtl5000, rt5651, hdmi-codec, wm_adsp)

   - minor ASoC platform fixes (AMD ACP, sun4i)"

* tag 'sound-4.16-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Revert power_save option default value
  ALSA: pcm: Fix UAF in snd_pcm_oss_get_formats()
  ALSA: seq: Clear client entry before deleting else at closing
  ALSA: seq: Fix possible UAF in snd_seq_check_queue()
  ASoC: amd: 16bit resolution support for i2s sp instance
  ASoC: wm_adsp: For TLV controls only register TLV get/set
  ASoC: sun4i-i2s: Fix RX slot number of SUN8I
  ASoC: hdmi-codec: Fix module unloading caused kernel crash
  ASoC: rt5651: Fix regcache sync errors on resume
  ASoC: sgtl5000: Fix suspend/resume
  MAINTAINERS: Add myself as sgtl5000 maintainer
  ASoC: samsung: Add the DT binding files entry to MAINTAINERS
  sgtl5000: change digital_mute policy

Merge tag 'for-4.16/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - a stable DM multipath fix to restore ability to pass integrity data

 - two DM multipath fixes for a fix that was merged into 4.16-rc5

* tag 'for-4.16/dm-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm mpath: fix passing integrity data
  dm mpath: eliminate need to use scsi_device_from_queue
  dm mpath: fix uninitialized 'pg_init_wait' waitqueue_head NULL pointer

This is to fix warning got as:

[ 6730.476938] ------------[ cut here ]------------
[ 6730.476979] Bad or missing usercopy whitelist? Kernel memory exposure attempt detected from SLAB object 'gvt-g_vgpu_workload' (offset 120, size 4)!
[ 6730.477021] WARNING: CPU: 2 PID: 441 at mm/usercopy.c:81 usercopy_warn+0x7e/0xa0
[ 6730.477042] Modules linked in: tun(E) bridge(E) stp(E) llc(E) kvmgt(E) x86_pkg_temp_thermal(E) vfio_mdev(E) intel_powerclamp(E) mdev(E) coretemp(E) vfio_iommu_type1(E) vfio(E) kvm_intel(E) kvm(E) hid_generic(E) irqbypass(E) crct10dif_pclmul(E) crc32_pclmul(E) usbhid(E) i915(E) crc32c_intel(E) hid(E) ghash_clmulni_intel(E) pcbc(E) aesni_intel(E) aes_x86_64(E) crypto_simd(E) cryptd(E) glue_helper(E) intel_cstate(E) idma64(E) evdev(E) virt_dma(E) iTCO_wdt(E) intel_uncore(E) intel_rapl_perf(E) intel_lpss_pci(E) sg(E) shpchp(E) mei_me(E) pcspkr(E) iTCO_vendor_support(E) intel_lpss(E) intel_pch_thermal(E) prime_numbers(E) mei(E) mfd_core(E) video(E) acpi_pad(E) button(E) binfmt_misc(E) ip_tables(E) x_tables(E) autofs4(E) ext4(E) crc16(E) mbcache(E) jbd2(E) fscrypto(E) sd_mod(E) e1000e(E) xhci_pci(E) sdhci_pci(E)
[ 6730.477244]  ptp(E) cqhci(E) xhci_hcd(E) pps_core(E) sdhci(E) mmc_core(E) i2c_i801(E) usbcore(E) thermal(E) fan(E)
[ 6730.477276] CPU: 2 PID: 441 Comm: gvt workload 0 Tainted: G            E    4.16.0-rc1-gvt-staging-0213+ #127
[ 6730.477303] Hardware name:  /NUC6i5SYB, BIOS SYSKLi35.86A.0039.2016.0316.1747 03/16/2016
[ 6730.477326] RIP: 0010:usercopy_warn+0x7e/0xa0
[ 6730.477340] RSP: 0018:ffffba6301223d18 EFLAGS: 00010286
[ 6730.477355] RAX: 0000000000000000 RBX: ffff8f41caae9838 RCX: 0000000000000006
[ 6730.477375] RDX: 0000000000000007 RSI: 0000000000000082 RDI: ffff8f41dad166f0
[ 6730.477395] RBP: 0000000000000004 R08: 0000000000000576 R09: 0000000000000000
[ 6730.477415] R10: ffffffffb1293fb2 R11: 00000000ffffffff R12: 0000000000000001
[ 6730.477447] R13: ffff8f41caae983c R14: ffff8f41caae9838 R15: 00007f183ca2b000
[ 6730.477467] FS:  0000000000000000(0000) GS:ffff8f41dad00000(0000) knlGS:0000000000000000
[ 6730.477489] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 6730.477506] CR2: 0000559462817291 CR3: 000000028b46c006 CR4: 00000000003626e0
[ 6730.477526] Call Trace:
[ 6730.477537]  __check_object_size+0x9c/0x1a0
[ 6730.477562]  __kvm_write_guest_page+0x45/0x90 [kvm]
[ 6730.477585]  kvm_write_guest+0x46/0x80 [kvm]
[ 6730.477599]  kvmgt_rw_gpa+0x9b/0xf0 [kvmgt]
[ 6730.477642]  workload_thread+0xa38/0x1040 [i915]
[ 6730.477659]  ? do_wait_intr_irq+0xc0/0xc0
[ 6730.477673]  ? finish_wait+0x80/0x80
[ 6730.477707]  ? clean_workloads+0x120/0x120 [i915]
[ 6730.477722]  kthread+0x111/0x130
[ 6730.477733]  ? _kthread_create_worker_on_cpu+0x60/0x60
[ 6730.477750]  ? exit_to_usermode_loop+0x6f/0xb0
[ 6730.477766]  ret_from_fork+0x35/0x40
[ 6730.477777] Code: 48 c7 c0 20 e3 25 b1 48 0f 44 c2 41 50 51 41 51 48 89 f9 49 89 f1 4d 89 d8 4c 89 d2 48 89 c6 48 c7 c7 78 e3 25 b1 e8 b2 bc e4 ff <0f> ff 48 83 c4 18 c3 48 c7 c6 09 d0 26 b1 49 89 f1 49 89 f3 eb
[ 6730.477849] ---[ end trace cae869c1c323e45a ]---

By whitelist guest page write from workload struct allocated from kmem cache.
Reviewed-by: Hang Yuan <hang.yuan@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
(cherry picked from commit 5627705406874df57fdfad3b4e0c9aedd3b007df)

Once the ring buffer is copied to ring_scan_buffer and scanned,
the shadow batch buffer start address is only updated into
ring_scan_buffer, not the real ring address allocated through
intel_ring_begin in later copy_workload_to_ring_buffer.

This patch is only to set the right shadow batch buffer address
from Ring buffer, not include the shadow_wa_ctx.

v2:
- refine some comments. (Zhenyu)
v3:
- fix typo in title. (Zhenyu)
v4:
- remove the unnecessary comments. (Zhenyu)
- add comments in bb_start_cmd_va update. (Zhenyu)

Fixes: 0a53bc07 ("drm/i915/gvt: Separate cmd scan from request allocation")
Cc: stable@vger.kernel.org  # v4.15
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yulei Zhang <yulei.zhang@intel.com>
Signed-off-by: fred gao <fred.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

Pull SCSI fixes from James Bottomley:
 "This is four patches, consisting of one regression from the merge
  window (qla2xxx), one long-standing memory leak (sd_zbc), one event
  queue mislabelling which we want to eliminate to discourage the
  pattern (mpt3sas), and one behaviour change because re-reading the
  partition table shouldn't clear the ro flag"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: sd: Keep disk read-only when re-reading partition
  scsi: qla2xxx: Fix crashes in qla2x00_probe_one on probe failure
  scsi: sd_zbc: Fix potential memory leak
  scsi: mpt3sas: Do not mark fw_event workqueue as WQ_MEM_RECLAIM

geo->keylen cannot be larger than 4.  So we might as well make
fixed-size allocations.

Given the one remaining user, geo->keylen cannot even be larger than 1.
Logfs used to have 64bit and 128bit keys, tcm_qla2xxx only has 32bit
keys.  But let's not break the code if we don't have to.
Signed-off-by: Joern Engel <joern@purestorage.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull percpu_ref rcu fixes from Tejun Heo:
 "Jann Horn found that aio was depending on the internal RCU grace
  periods of percpu-ref and that it's broken because aio uses regular
  RCU while percpu_ref uses sched-RCU.

  Depending on percpu_ref's internal grace periods isn't a good idea
  because

   - The RCU type might not match.

   - percpu_ref's grace periods are used to switch to atomic mode. They
     aren't between the last put and the invocation of the last release.
     This is easy to get confused about and can lead to subtle bugs.

   - percpu_ref might not have grace periods at all depending on its
     current operation mode.

  This patchset audits and fixes percpu_ref users for their RCU usages"

[ There's a continuation of this series that clarifies percpu_ref
  documentation that the internal grace periods must not be depended
  upon, and introduces rcu_work to simplify bouncing to a workqueue
  after an RCU grace period.

  That will go in for 4.17 - this is just the minimal set with the fixes
  that are tagged for -stable ]

* 'percpu_ref-rcu-audit-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc:
  RDMAVT: Fix synchronization around percpu_ref
  fs/aio: Use RCU accessors for kioctx_table->table[]
  fs/aio: Add explicit RCU grace period when freeing kioctx

This reverts commit 864b75f9.

Commit 864b75f9 ("mm/page_alloc: fix memmap_init_zone pageblock
alignment") modified the logic in memmap_init_zone() to initialize
struct pages associated with invalid PFNs, to appease a VM_BUG_ON()
in move_freepages(), which is redundant by its own admission, and
dereferences struct page fields to obtain the zone without checking
whether the struct pages in question are valid to begin with.

Commit 864b75f9 only makes it worse, since the rounding it does
may cause pfn assume the same value it had in a prior iteration of
the loop, resulting in an infinite loop and a hang very early in the
boot. Also, since it doesn't perform the same rounding on start_pfn
itself but only on intermediate values following an invalid PFN, we
may still hit the same VM_BUG_ON() as before.

So instead, let's fix this at the core, and ensure that the BUG
check doesn't dereference struct page fields of invalid pages.

Fixes: 864b75f9 ("mm/page_alloc: fix memmap_init_zone pageblock alignment")
Tested-by: Jan Glauber <jglauber@cavium.com>
Tested-by: Shanker Donthineni <shankerd@codeaurora.org>
Cc: Daniel Vacek <neelx@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Paul Burton <paul.burton@imgtec.com>
Cc: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'drm-intel-fixes-2018-03-14' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

- 1 display fix for bxt
- 1 gem fix for fences
- 1 gem/pm fix for rps freq

* tag 'drm-intel-fixes-2018-03-14' of git://anongit.freedesktop.org/drm/drm-intel:
  drm/i915: Kick the rps worker when changing the boost frequency
  drm/i915: Only prune fences after wait-for-all
  drm/i915: Enable VBT based BL control for DP

A few fixes for 4.16:
- Fix a backlight S/R regression on amdgpu
- Fix prime teardown on radeon and amdgpu
- DP fix for amdgpu

* 'drm-fixes-4.16' of git://people.freedesktop.org/~agd5f/linux:
  drm/amdgpu/dce: Don't turn off DP sink when disconnected
  drm/amdgpu: save/restore backlight level in legacy dce code
  drm/radeon: fix prime teardown order
  drm/amdgpu: fix prime teardown order

This patch addresses an issue that causes fiemap to falsely
report a shared extent.  The test case is as follows:

xfs_io -f -d -c "pwrite -b 16k 0 64k" -c "fiemap -v" /media/scratch/file5
sync
xfs_io  -c "fiemap -v" /media/scratch/file5

which gives the resulting output:

wrote 65536/65536 bytes at offset 0
64 KiB, 4 ops; 0.0000 sec (121.359 MiB/sec and 7766.9903 ops/sec)
/media/scratch/file5:
 EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
   0: [0..127]:        24576..24703       128 0x2001
/media/scratch/file5:
 EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
   0: [0..127]:        24576..24703       128   0x1

This is because btrfs_check_shared calls find_parent_nodes
repeatedly in a loop, passing a share_check struct to report
the count of shared extent. But btrfs_check_shared does not
re-initialize the count value to zero for subsequent calls
from the loop, resulting in a false share count value. This
is a regressive behavior from 4.13.

With proper re-initialization the test result is as follows:

wrote 65536/65536 bytes at offset 0
64 KiB, 4 ops; 0.0000 sec (110.035 MiB/sec and 7042.2535 ops/sec)
/media/scratch/file5:
 EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
   0: [0..127]:        24576..24703       128   0x1
/media/scratch/file5:
 EXT: FILE-OFFSET      BLOCK-RANGE      TOTAL FLAGS
   0: [0..127]:        24576..24703       128   0x1

which corrects the regression.

Fixes: 3ec4d323 ("btrfs: allow backref search checks for shared extents")
Signed-off-by: Edmund Nadolski <enadolski@suse.com>
[ add text from cover letter to changelog ]
Signed-off-by: David Sterba <dsterba@suse.com>

On detaching of a disk which is a part of a RAID6 filesystem, the
following kernel OOPS may happen:

[63122.680461] BTRFS error (device sdo): bdev /dev/sdo errs: wr 0, rd 0, flush 1, corrupt 0, gen 0
[63122.719584] BTRFS warning (device sdo): lost page write due to IO error on /dev/sdo
[63122.719587] BTRFS error (device sdo): bdev /dev/sdo errs: wr 1, rd 0, flush 1, corrupt 0, gen 0
[63122.803516] BTRFS warning (device sdo): lost page write due to IO error on /dev/sdo
[63122.803519] BTRFS error (device sdo): bdev /dev/sdo errs: wr 2, rd 0, flush 1, corrupt 0, gen 0
[63122.863902] BTRFS critical (device sdo): fatal error on device /dev/sdo
[63122.935338] BUG: unable to handle kernel NULL pointer dereference at 0000000000000080
[63122.946554] IP: fail_bio_stripe+0x58/0xa0 [btrfs]
[63122.958185] PGD 9ecda067 P4D 9ecda067 PUD b2b37067 PMD 0
[63122.971202] Oops: 0000 [#1] SMP
[63123.006760] CPU: 0 PID: 3979 Comm: kworker/u8:9 Tainted: G W 4.14.2-16-scst34x+ #8
[63123.007091] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[63123.007402] Workqueue: btrfs-worker btrfs_worker_helper [btrfs]
[63123.007595] task: ffff880036ea4040 task.stack: ffffc90006384000
[63123.007796] RIP: 0010:fail_bio_stripe+0x58/0xa0 [btrfs]
[63123.007968] RSP: 0018:ffffc90006387ad8 EFLAGS: 00010287
[63123.008140] RAX: 0000000000000002 RBX: ffff88004beaa0b8 RCX: ffff8800b2bd5690
[63123.008359] RDX: 0000000000000000 RSI: ffff88007bb43500 RDI: ffff88004beaa000
[63123.008621] RBP: ffffc90006387ae8 R08: 0000000099100000 R09: ffff8800b2bd5600
[63123.008840] R10: 0000000000000004 R11: 0000000000010000 R12: ffff88007bb43500
[63123.009059] R13: 00000000fffffffb R14: ffff880036fc5180 R15: 0000000000000004
[63123.009278] FS: 0000000000000000(0000) GS:ffff8800b7000000(0000) knlGS:0000000000000000
[63123.009564] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[63123.009748] CR2: 0000000000000080 CR3: 00000000b0866000 CR4: 00000000000406f0
[63123.009969] Call Trace:
[63123.010085] raid_write_end_io+0x7e/0x80 [btrfs]
[63123.010251] bio_endio+0xa1/0x120
[63123.010378] generic_make_request+0x218/0x270
[63123.010921] submit_bio+0x66/0x130
[63123.011073] finish_rmw+0x3fc/0x5b0 [btrfs]
[63123.011245] full_stripe_write+0x96/0xc0 [btrfs]
[63123.011428] raid56_parity_write+0x117/0x170 [btrfs]
[63123.011604] btrfs_map_bio+0x2ec/0x320 [btrfs]
[63123.011759] ? ___cache_free+0x1c5/0x300
[63123.011909] __btrfs_submit_bio_done+0x26/0x50 [btrfs]
[63123.012087] run_one_async_done+0x9c/0xc0 [btrfs]
[63123.012257] normal_work_helper+0x19e/0x300 [btrfs]
[63123.012429] btrfs_worker_helper+0x12/0x20 [btrfs]
[63123.012656] process_one_work+0x14d/0x350
[63123.012888] worker_thread+0x4d/0x3a0
[63123.013026] ? _raw_spin_unlock_irqrestore+0x15/0x20
[63123.013192] kthread+0x109/0x140
[63123.013315] ? process_scheduled_works+0x40/0x40
[63123.013472] ? kthread_stop+0x110/0x110
[63123.013610] ret_from_fork+0x25/0x30
[63123.014469] RIP: fail_bio_stripe+0x58/0xa0 [btrfs] RSP: ffffc90006387ad8
[63123.014678] CR2: 0000000000000080
[63123.016590] ---[ end trace a295ea7259c17880 ]—

This is reproducible in a cycle, where a series of writes is followed by
SCSI device delete command. The test may take up to few minutes.

Fixes: 74d46992 ("block: replace bi_bdev with a gendisk pointer and partitions index")
[ no signed-off-by provided ]
Author: Dmitriy Gorokh <Dmitriy.Gorokh@wdc.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Turning off the sink in this case causes various issues, because
userspace expects it to stay on until it turns it off explicitly.

Instead, turn the sink off and back on when a display is connected
again. This dance seems necessary for link training to work correctly.

Bugzilla: https://bugs.freedesktop.org/105308
Cc: stable@vger.kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Save/restore the backlight level scratch register in S3/S4 so the
backlight level comes back at the previously requested level.

Bug: https://bugzilla.kernel.org/show_bug.cgi?id=199047
Fixes: 4ec6ecf4 (drm/amdgpu: drop scratch regs save and restore from S3/S4 handling)
Acked-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

We unmapped imported DMA-bufs when the GEM handle was dropped, not when the
hardware was done with the buffere.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
CC: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

We unmapped imported DMA-bufs when the GEM handle was dropped, not when the
hardware was done with the buffere.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
CC: stable@vger.kernel.org
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

Pull x86 platform drives fixes from Darren Hart:

 - DELL_SMBIOS conditionally depends on ACPI_WMI in the same way it
   depends on DCDBAS, update the Kconfig accordingly.

 - fix the dell driver init order to ensure that the driver dependencies
   are met, avoiding race conditions resulting in boot failure on
   certain systems when the drivers are built-in.

* tag 'platform-drivers-x86-v4.16-7' of git://git.infradead.org/linux-platform-drivers-x86:
  platform/x86: Fix dell driver init order
  platform/x86: dell-smbios: Resolve dependency error on ACPI_WMI

After v4.12 commit e2460f2a ("dm: mark targets that pass integrity
data"), dm-multipath, e.g. on DIF+DIX SCSI disk paths, does not support
block integrity any more. So add it to the whitelist.

This is also a pre-requisite to use block integrity with other dm layer(s)
on top of multipath, such as kpartx partitions (dm-linear) or LVM.

Also, bump target version to reflect this fix.

Fixes: e2460f2a ("dm: mark targets that pass integrity data")
Cc: <stable@vger.kernel.org> #4.12+
Bisected-by: Fedor Loshakov <loshakov@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

rvt_mregion uses percpu_ref for reference counting and RCU to protect
accesses from lkey_table.  When a rvt_mregion needs to be freed, it
first gets unregistered from lkey_table and then rvt_check_refs() is
called to wait for in-flight usages before the rvt_mregion is freed.

rvt_check_refs() seems to have a couple issues.

* It has a fast exit path which tests percpu_ref_is_zero().  However,
  a percpu_ref reading zero doesn't mean that the object can be
  released.  In fact, the ->release() callback might not even have
  started executing yet.  Proceeding with freeing can lead to
  use-after-free.

* lkey_table is RCU protected but there is no RCU grace period in the
  free path.  percpu_ref uses RCU internally but it's sched-RCU whose
  grace periods are different from regular RCU.  Also, it generally
  isn't a good idea to depend on internal behaviors like this.

To address the above issues, this patch removes the fast exit and adds
an explicit synchronize_rcu().
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Cc: Mike Marciniszyn <mike.marciniszyn@intel.com>
Cc: linux-rdma@vger.kernel.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>

While converting ioctx index from a list to a table, db446a08
("aio: convert the ioctx list to table lookup v3") missed tagging
kioctx_table->table[] as an array of RCU pointers and using the
appropriate RCU accessors.  This introduces a small window in the
lookup path where init and access may race.

Mark kioctx_table->table[] with __rcu and use the approriate RCU
accessors when using the field.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Fixes: db446a08 ("aio: convert the ioctx list to table lookup v3")
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org # v3.12+

While fixing refcounting, e34ecee2 ("aio: Fix a trinity splat")
incorrectly removed explicit RCU grace period before freeing kioctx.
The intention seems to be depending on the internal RCU grace periods
of percpu_ref; however, percpu_ref uses a different flavor of RCU,
sched-RCU.  This can lead to kioctx being freed while RCU read
protected dereferences are still in progress.

Fix it by updating free_ioctx() to go through call_rcu() explicitly.

v2: Comment added to explain double bouncing.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Jann Horn <jannh@google.com>
Fixes: e34ecee2 ("aio: Fix a trinity splat")
Cc: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable@vger.kernel.org # v3.13+

Update the initcall ordering to satisfy the following dependency
ordering:

1. DCDBAS, ACPI_WMI
2. DELL_SMBIOS, DELL_RBTN
3. DELL_LAPTOP, DELL_WMI

By assigning them to the following initcall levels:

subsys_initcall: DCDBAS, ACPI_WMI
module_init: DELL_SMBIOS, DELL_RBTN
late_initcall: DELL_LAPTOP, DELL_WMI

Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Mario.Limonciello@dell.com
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>

Similarly to DCDBAS for DELL_SMBIOS_SMM, if DELL_SMBIOS_WMI is enabled,
DELL_SMBIOS becomes dependent on ACPI_WMI. Update the depends lines to
prevent a configuration where DELL_SMBIOS=y and either backend
dependency =m. Update the comment accordingly.

Cc: Mario Limonciello <mario.limonciello@dell.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>