Pull xen fixes from Juergen Gross:
 "Several fixes, mostly for rather recent regressions when running under
  Xen"

* tag 'for-linus-4.20a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: remove size limit of privcmd-buf mapping interface
  xen: fix xen_qlock_wait()
  x86/xen: fix pv boot
  xen-blkfront: fix kernel panic with negotiate_mq error path
  xen/grant-table: Fix incorrect gnttab_dma_free_pages() pr_debug message
  CONFIG_XEN_PV breaks xen_create_contiguous_region on ARM

Pull arm64 fixes from Catalin Marinas:

 - Fix occasional page fault during boot due to memblock resizing before
   the linear map is up.

 - Define NET_IP_ALIGN to 0 to improve the DMA performance on some
   platforms.

 - lib/raid6 test build fix.

 - .mailmap update for Punit Agrawal

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: memblock: don't permit memblock resizing until linear mapping is up
  arm64: mm: define NET_IP_ALIGN to 0
  lib/raid6: Fix arm64 test build
  mailmap: Update email for Punit Agrawal

Pull i2c updates from Wolfram Sang:
 "I2C has one bugfix (qcom-geni driver), one arch enablement (i2c-omap
  driver, no code change), and a new driver (nvidia-gpu) this time"

* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  usb: typec: ucsi: add support for Cypress CCGx
  i2c: nvidia-gpu: make pm_ops static
  i2c: add i2c bus driver for NVIDIA GPU
  i2c: qcom-geni: Fix runtime PM mismatch with child devices
  MAINTAINERS: Add entry for i2c-omap driver
  i2c: omap: Enable for ARCH_K3
  dt-bindings: i2c: omap: Add new compatible for AM654 SoCs

Pull Devicetree fixes from Rob Herring:

 - Add validation of NUMA distance map to prevent crashes with bad map

 - Fix setting of dma_mask

* tag 'devicetree-fixes-for-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  of, numa: Validate some distance map rules
  of/device: Really only set bus DMA mask when appropriate

Pull block layer fixes from Jens Axboe:

 - Two fixes for an ubd regression, one for missing locking, and one for
   a missing initialization of a field. The latter was an old latent
   bug, but it's now visible and triggers (Me, Anton Ivanov)

 - Set of NVMe fixes via Christoph, but applied manually due to a git
   tree mixup (Christoph, Sagi)

 - Fix for a discard split regression, in three patches (Ming)

 - Update libata git trees (Geert)

 - SPDX identifier for sata_rcar (Kuninori Morimoto)

 - Virtual boundary merge fix (Johannes)

 - Preemptively clear memory we are going to pass to userspace, in case
   the driver does a short read (Keith)

* tag 'for-linus-20181109' of git://git.kernel.dk/linux-block:
  block: make sure writesame bio is aligned with logical block size
  block: cleanup __blkdev_issue_discard()
  block: make sure discard bio is aligned with logical block size
  Revert "nvmet-rdma: use a private workqueue for delete"
  nvme: make sure ns head inherits underlying device limits
  nvmet: don't try to add ns to p2p map unless it actually uses it
  sata_rcar: convert to SPDX identifiers
  ubd: fix missing initialization of io_req
  block: Clear kernel memory before copying to user
  MAINTAINERS: Fix remaining pointers to obsolete libata.git
  ubd: fix missing lock around request issue
  block: respect virtual boundary mask in bvecs

Pull Ceph fixes from Ilya Dryomov:
 "Two CephFS fixes (copy_file_range and quota) and a small feature bit
  cleanup"

* tag 'ceph-for-4.20-rc2' of https://github.com/ceph/ceph-client:
  libceph: assume argonaut on the server side
  ceph: quota: fix null pointer dereference in quota check
  ceph: add destination file data sync before doing any remote copy

Pull MIPS fixes from Paul Burton:
 "A couple of small MIPS fixes for 4.20:

   - Extend an array to avoid overruns on some Octeon hardware, fixing a
     bug introduced in 4.3.

   - Fix a coherent DMA regression for systems without cache-coherent
     DMA introduced in the 4.20 merge window"

* tag 'mips_fixes_4.20_2' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux:
  MIPS: Fix `dma_alloc_coherent' returning a non-coherent allocation
  MIPS: OCTEON: fix out of bounds array access on CN68XX

Latest NVIDIA GPU cards have a Cypress CCGx Type-C controller
over I2C interface.

This UCSI I2C driver uses I2C bus driver interface for communicating
with Type-C controller.
Signed-off-by: Ajay Gupta <ajayg@nvidia.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

sparse rightfully says:

warning: symbol 'gpu_i2c_driver_pm' was not declared. Should it be static?
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Latest NVIDIA GPU card has USB Type-C interface. There is a
Type-C controller which can be accessed over I2C.

This driver adds I2C bus driver to communicate with Type-C controller.
I2C client driver will be part of USB Type-C UCSI driver.
Signed-off-by: Ajay Gupta <ajayg@nvidia.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[wsa: kept Makefile sorting]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

We need to enable runtime PM on this i2c controller before populating
child devices with i2c_add_adapter(). Otherwise, if a child device uses
runtime PM and stays runtime PM enabled we'll get the following warning
at boot.

 Enabling runtime PM for inactive device (a98000.i2c) with active children

[...]

 Call trace:
  pm_runtime_enable+0xd8/0xf8
  geni_i2c_probe+0x440/0x460
  platform_drv_probe+0x74/0xc8
[...]

Let's move the runtime PM enabling and setup to before we add the
adapter, so that this device can respond to runtime PM requests from
children.

Fixes: 37692de5 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Add separate entry for i2c-omap and add my name as maintainer for this
driver.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Allow I2C_OMAP to be built for K3 platforms.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

AM654 SoCs have same I2C IP as OMAP SoCs. Add new compatible to
handle AM654 SoCs. While at that reformat the existing compatible list
for older SoCs to list one valid compatible per line.
Signed-off-by: Vignesh R <vigneshr@ti.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

Currently the size of hypercall buffers allocated via
/dev/xen/hypercall is limited to a default of 64 memory pages. For live
migration of guests this might be too small as the page dirty bitmask
needs to be sized according to the size of the guest. This means
migrating a 8GB sized guest is already exhausting the default buffer
size for the dirty bitmap.

There is no sensible way to set a sane limit, so just remove it
completely. The device node's usage is limited to root anyway, so there
is no additional DOS scenario added by allowing unlimited buffers.

While at it make the error path for the -ENOMEM case a little bit
cleaner by setting n_pages to the number of successfully allocated
pages instead of the target size.

Fixes: c51b3c63 ("xen: add new hypercall buffer mapping device")
Cc: <stable@vger.kernel.org> #4.18
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Commit a8565319 ("xen: make xen_qlock_wait() nestable")
introduced a regression for Xen guests running fully virtualized
(HVM or PVH mode). The Xen hypervisor wouldn't return from the poll
hypercall with interrupts disabled in case of an interrupt (for PV
guests it does).

So instead of disabling interrupts in xen_qlock_wait() use a nesting
counter to avoid calling xen_clear_irq_pending() in case
xen_qlock_wait() is nested.

Fixes: a8565319 ("xen: make xen_qlock_wait() nestable")
Cc: stable@vger.kernel.org
Reported-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Tested-by: Sander Eikelenboom <linux@eikelenboom.it>
Signed-off-by: Juergen Gross <jgross@suse.com>

Obviously the created writesame bio has to be aligned with logical block
size, and use bio_allowed_max_sectors() to retrieve this number.

Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Fixes: b49a0871 ("block: remove split code in blkdev_issue_{discard,write_same}")
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Cleanup __blkdev_issue_discard() a bit:

- remove local variable of 'end_sect'
- remove code block of 'fail'

Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Obviously the created discard bio has to be aligned with logical block size.

This patch introduces the helper of bio_allowed_max_sectors() for
this purpose.

Cc: stable@vger.kernel.org
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Xiao Ni <xni@redhat.com>
Cc: Mariusz Dabrowski <mariusz.dabrowski@intel.com>
Fixes: 744889b7 ("block: don't deal with discard limit in blkdev_issue_discard()")
Fixes: a22c4d7e ("block: re-add discard_granularity and alignment checks")
Reported-by: Rui Salvaterra <rsalvaterra@gmail.com>
Tested-by: Rui Salvaterra <rsalvaterra@gmail.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

This reverts commit 2acf70ad.

The commit never really fixed the intended issue and caused all
kinds of other issues, including a use before initialization.
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Whenever we update ns_head info, we need to make sure it is still
compatible with all underlying backing devices because although nvme
multipath doesn't have any explicit use of these limits, other devices
can still be stacked on top of it which may rely on the underlying limits.
Start with unlimited stacking limits, and every info update iterate over
siblings and adjust queue limits.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Even without CONFIG_P2PDMA this results in a error print:
nvmet: no peer-to-peer memory is available that's supported by rxe0 and /dev/nullb0

Fixes: c6925093 ("nvmet: Optionally use PCI P2P memory")
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull s390 fixes from Martin Schwidefsky:

 - A fix for the pgtable_bytes misaccounting on s390. The patch changes
   common code part in regard to page table folding and adds extra
   checks to mm_[inc|dec]_nr_[pmds|puds].

 - Add FORCE for all build targets using if_changed

 - Use non-loadable phdr for the .vmlinux.info section to avoid a
   segment overlap that confuses kexec

 - Cleanup the attribute definition for the diagnostic sampling

 - Increase stack size for CONFIG_KASAN=y builds

 - Export __node_distance to fix a build error

 - Correct return code of a PMU event init function

 - An update for the default configs

* tag 's390-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
  s390/perf: Change CPUM_CF return code in event init function
  s390: update defconfigs
  s390/mm: Fix ERROR: "__node_distance" undefined!
  s390/kasan: increase instrumented stack size to 64k
  s390/cpum_sf: Rework attribute definition for diagnostic sampling
  s390/mm: fix mis-accounting of pgtable_bytes
  mm: add mm_pxd_folded checks to pgtable_bytes accounting functions
  mm: introduce mm_[p4d|pud|pmd]_folded
  mm: make the __PAGETABLE_PxD_FOLDED defines non-empty
  s390: avoid vmlinux segments overlap
  s390/vdso: add missing FORCE to build targets
  s390/decompressor: add missing FORCE to build targets

Commit 9da3f2b7 ("x86/fault: BUG() when uaccess helpers fault on
kernel addresses") introduced a regression for booting Xen PV guests.

Xen PV guests are using __put_user() and __get_user() for accessing the
p2m map (physical to machine frame number map) as accesses might fail
in case of not populated areas of the map.

With above commit using __put_user() and __get_user() for accessing
kernel pages is no longer valid. So replace the Xen hack by adding
appropriate p2m access functions using the default fixup handler.

Fixes: 9da3f2b7 ("x86/fault: BUG() when uaccess helpers fault on kernel addresses")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>

Pull xfs fixes from Darrick Wong:

 - fix incorrect dropping of error code from bmap

 - print buffer offsets instead of useless hashed pointers when dumping
   corrupt metadata

 - fix integer overflow in attribute verifier

* tag 'xfs-4.20-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: fix overflow in xfs_attr3_leaf_verify
  xfs: print buffer offsets when dumping corrupt buffers
  xfs: Fix error code in 'xfs_ioc_getbmap()'

Merge tag 'led-fixes-for-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED fixes from Jacek Anaszewski:
 "All three fixes are related to the newly added pattern trigger:

   - remove mutex_lock() from timer callback, which would trigger
     problems related to sleeping in atomic context, the removal is
     harmless since mutex protection turned out to be redundant in this
     case

   - fix pattern parsing to properly handle intervals with brightness == 0

   - fix typos in the ABI documentation"

* tag 'led-fixes-for-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  Documentation: ABI: led-trigger-pattern: Fix typos
  leds: trigger: Fix sleeping function called from invalid context
  Fix pattern handling optimalization

Pull sound fixes from Takashi Iwai:
 "Two small regression fixes for HD-audio: one about vga_switcheroo and
  runtime PM, and another about Oops on some Thinkpads"

* tag 'sound-4.20-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound:
  ALSA: hda - Fix incorrect clearance of thinkpad_acpi hooks
  vga_switcheroo: Fix missing gpu_bound call at audio client registration

Currently the NUMA distance map parsing does not validate the distance
table for the distance-matrix rules 1-2 in [1].

However the arch NUMA code may enforce some of these rules, but not all.
Such is the case for the arm64 port, which does not enforce the rule that
the distance between separates nodes cannot equal LOCAL_DISTANCE.

The patch adds the following rules validation:
- distance of node to self equals LOCAL_DISTANCE
- distance of separate nodes > LOCAL_DISTANCE

This change avoids a yet-unresolved crash reported in [2].

A note on dealing with symmetrical distances between nodes:

Validating symmetrical distances between nodes is difficult. If it were
mandated in the bindings that every distance must be recorded in the
table, then it would be easy. However, it isn't.

In addition to this, it is also possible to record [b, a] distance only
(and not [a, b]). So, when processing the table for [b, a], we cannot
assert that current distance of [a, b] != [b, a] as invalid, as [a, b]
distance may not be present in the table and current distance would be
default at REMOTE_DISTANCE.

As such, we maintain the policy that we overwrite distance [a, b] = [b, a]
for b > a. This policy is different to kernel ACPI SLIT validation, which
allows non-symmetrical distances (ACPI spec SLIT rules allow it). However,
the distance debug message is dropped as it may be misleading (for a distance
which is later overwritten).

Some final notes on semantics:

- It is implied that it is the responsibility of the arch NUMA code to
  reset the NUMA distance map for an error in distance map parsing.

- It is the responsibility of the FW NUMA topology parsing (whether OF or
  ACPI) to enforce NUMA distance rules, and not arch NUMA code.

[1] Documents/devicetree/bindings/numa.txt
[2] https://www.spinics.net/lists/arm-kernel/msg683304.html

Cc: stable@vger.kernel.org # 4.7
Signed-off-by: John Garry <john.garry@huawei.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>

of_dma_configure() was *supposed* to be following the same logic as
acpi_dma_configure() and only setting bus_dma_mask if some range was
specified by the firmware. However, it seems that subtlety got lost in
the process of fitting it into the differently-shaped control flow, and
as a result the force_dma==true case ends up always setting the bus mask
to the 32-bit default, which is not what anyone wants.

Make sure we only touch it if the DT actually said so.

Fixes: 6c2fb2ea ("of/device: Set bus DMA mask as appropriate")
Reported-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Reported-by: Jean-Philippe Brucker <jean-philippe.brucker@arm.com>
Tested-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: John Stultz <john.stultz@linaro.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Robert Richter <robert.richter@cavium.com>
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>

Bhupesh reports that having numerous memblock reservations at early
boot may result in the following crash:

  Unable to handle kernel paging request at virtual address ffff80003ffe0000
  ...
  Call trace:
   __memcpy+0x110/0x180
   memblock_add_range+0x134/0x2e8
   memblock_reserve+0x70/0xb8
   memblock_alloc_base_nid+0x6c/0x88
   __memblock_alloc_base+0x3c/0x4c
   memblock_alloc_base+0x28/0x4c
   memblock_alloc+0x2c/0x38
   early_pgtable_alloc+0x20/0xb0
   paging_init+0x28/0x7f8

This is caused by the fact that we permit memblock resizing before the
linear mapping is up, and so the memblock_reserved() array is moved
into memory that is not mapped yet.

So let's ensure that this crash can no longer occur, by deferring to
call to memblock_allow_resize() to after the linear mapping has been
created.
Reported-by: Bhupesh Sharma <bhsharma@redhat.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

On arm64, there is no need to add 2 bytes of padding to the start of
each network buffer just to make the IP header appear 32-bit aligned.

Since this might actually adversely affect DMA performance some
platforms, let's override NET_IP_ALIGN to 0 to get rid of this
padding.
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Tested-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

No one is running pre-argonaut.  In addition one of the argonaut
features (NOSRCADDR) has been required since day one (and a half,
2.6.34 vs 2.6.35) of the kernel client.

Allow for the possibility of reusing these feature bits later.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Sage Weil <sage@redhat.com>

This patch fixes a possible null pointer dereference in
check_quota_exceeded, detected by the static checker smatch, with the
following warning:

   fs/ceph/quota.c:240 check_quota_exceeded()
    error: we previously assumed 'realm' could be null (see line 188)

Fixes: b7a29217 ("ceph: quota: support for ceph.quota.max_files")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

If we try to copy into a file that was just written, any data that is
remote copied will be overwritten by our buffered writes once they are
flushed.  When this happens, the call to invalidate_inode_pages2_range
will also return a -EBUSY error.

This patch fixes this by also sync'ing the destination file before
starting any copy.

Fixes: 503f82a9 ("ceph: support copy_file_range file operation")
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

This patch updates license to use SPDX-License-Identifier
instead of verbose license text.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

The SYNC path doesn't initialize io_req->error, which can cause
random errors. Before the conversion to blk-mq, we always
completed requests with BLK_STS_OK status, but now we actually
look at the error field and this issue becomes apparent.
Signed-off-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>

[axboe: fixed up commit message to explain what is actually going on]
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Pull compiler attribute fixlets from Miguel Ojeda:
 "Small improvements to Compiler Attributes:

   - Define asm_volatile_goto for non-gcc compilers (Nick Desaulniers)

   - Improve the explanation of compiler_attributes.h"

* tag 'compiler-attributes-for-linus-v4.20-rc2' of https://github.com/ojeda/linux:
  Compiler Attributes: improve explanation of header
  include/linux/compiler*.h: define asm_volatile_goto

Pull MTD fixes from Boris Brezillon:
 "MTD changes:
   - Kill a VLA in sa1100

  SPI NOR changes:
   - Make sure ->addr_width is restored when SFDP parsing fails
   - Propate errors happening in cqspi_direct_read_execute()

  NAND changes:
   - Fix kernel-doc mismatch
   - Fix nanddev_neraseblocks() to return the correct value
   - Avoid selection of BCH_CONST_PARAMS when some users require dynamic
     BCH settings"

* tag 'mtd/fixes-for-4.20-rc2' of git://git.infradead.org/linux-mtd:
  mtd: nand: Fix nanddev_pos_next_page() kernel-doc header
  mtd: sa1100: avoid VLA in sa1100_setup_mtd
  mtd: spi-nor: Reset nor->addr_width when SFDP parsing failed
  mtd: spi-nor: cadence-quadspi: Return error code in cqspi_direct_read_execute()
  mtd: nand: Fix nanddev_neraseblocks()
  mtd: nand: drop kernel-doc notation for a deleted function parameter
  mtd: docg3: don't set conflicting BCH_CONST_PARAMS option

Explain better what "optional" attributes are, and avoid calling
them so to avoid confusion. Simply retain "Optional" as a word
to look for in the comments.

Moreover, add a couple sentences to explain a bit more the intention
and the documentation links.
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>

The function perf_init_event() creates a new event and
assignes it to a PMU. This a done in a loop over all existing
PMUs. For each listed PMU the event init function is called
and if this function does return any other error than -ENOENT,
the loop is terminated the creation of the event fails.

If the event is invalid, return -ENOENT to try other PMUs.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>