Document change in required compiler version for KCSAN, and remove the
now redundant note about __no_kcsan and inlining problems with older
compilers.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-8-elver@google.com

Some compilers incorrectly inline small __no_kcsan functions, which then
results in instrumenting the accesses. For this reason, the 'noinline'
attribute was added to __no_kcsan_or_inline. All known versions of GCC
are affected by this. Supported versions of Clang are unaffected, and
never inline a no_sanitize function.

However, the attribute 'noinline' in __no_kcsan_or_inline causes
unexpected code generation in functions that are __no_kcsan and call a
__no_kcsan_or_inline function.

In certain situations it is expected that the __no_kcsan_or_inline
function is actually inlined by the __no_kcsan function, and *no* calls
are emitted. By removing the 'noinline' attribute, give the compiler
the ability to inline and generate the expected code in __no_kcsan
functions.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CANpmjNNOpJk0tprXKB_deiNAv_UmmORf1-2uajLhnLWQQ1hvoA@mail.gmail.com
Link: https://lkml.kernel.org/r/20200521142047.169334-6-elver@google.com

Clang (unlike GCC) removes reads before writes with matching addresses
in the same basic block. This is an optimization for TSAN, since writes
will always cause conflict if the preceding read would have.

However, for KCSAN we cannot rely on this option, because we apply
several special rules to writes, in particular when the
KCSAN_ASSUME_PLAIN_WRITES_ATOMIC option is selected. To avoid missing
potential data races, pass the -tsan-instrument-read-before-write option
to Clang if it is available [1].

[1] https://github.com/llvm/llvm-project/commit/151ed6aa38a3ec6c01973b35f684586b6e1c0f7eSigned-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-5-elver@google.com

In the kernel, the "volatile" keyword is used in various concurrent
contexts, whether in low-level synchronization primitives or for
legacy reasons. If supported by the compiler, it will be assumed
that aligned volatile accesses up to sizeof(long long) (matching
compiletime_assert_rwonce_type()) are atomic.

Recent versions of Clang [1] (GCC tentative [2]) can instrument
volatile accesses differently. Add the option (required) to enable the
instrumentation, and provide the necessary runtime functions. None of
the updated compilers are widely available yet (Clang 11 will be the
first release to support the feature).

[1] https://github.com/llvm/llvm-project/commit/5a2c31116f412c3b6888be361137efd705e05814
[2] https://gcc.gnu.org/pipermail/gcc-patches/2020-April/544452.html

This change allows removing of any explicit checks in primitives such as
READ_ONCE() and WRITE_ONCE().

 [ bp: Massage commit message a bit. ]
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-4-elver@google.com

The first version of Clang that supports -tsan-distinguish-volatile will
be able to support KCSAN. The first Clang release to do so, will be
Clang 11. This is due to satisfying all the following requirements:

1. Never emit calls to __tsan_func_{entry,exit}.

2. __no_kcsan functions should not call anything, not even
   kcsan_{enable,disable}_current(), when using __{READ,WRITE}_ONCE => Requires
   leaving them plain!

3. Support atomic_{read,set}*() with KCSAN, which rely on
   arch_atomic_{read,set}*() using __{READ,WRITE}_ONCE() => Because of
   #2, rely on Clang 11's -tsan-distinguish-volatile support. We will
   double-instrument atomic_{read,set}*(), but that's reasonable given
   it's still lower cost than the data_race() variant due to avoiding 2
   extra calls (kcsan_{en,dis}able_current() calls).

4. __always_inline functions inlined into __no_kcsan functions are never
   instrumented.

5. __always_inline functions inlined into instrumented functions are
   instrumented.

6. __no_kcsan_or_inline functions may be inlined into __no_kcsan functions =>
   Implies leaving 'noinline' off of __no_kcsan_or_inline.

7. Because of #6, __no_kcsan and __no_kcsan_or_inline functions should never be
   spuriously inlined into instrumented functions, causing the accesses of the
   __no_kcsan function to be instrumented.

Older versions of Clang do not satisfy #3. The latest GCC currently
doesn't support at least #1, #3, and #7.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com
Link: https://lkml.kernel.org/r/20200521142047.169334-7-elver@google.com

To avoid inserting  __tsan_func_{entry,exit}, add option if supported by
compiler. Currently only Clang can be told to not emit calls to these
functions. It is safe to not emit these, since KCSAN does not rely on
them.

Note that, if we disable __tsan_func_{entry,exit}(), we need to disable
tail-call optimization in sanitized compilation units, as otherwise we
may skip frames in the stack trace; in particular when the tail called
function is one of the KCSAN's runtime functions, and a report is
generated, we might miss the function where the actual access occurred.

Since __tsan_func_{entry,exit}() insertion effectively disabled
tail-call optimization, there should be no observable change.

This was caught and confirmed with kcsan-test & UNWINDER_ORC.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200521142047.169334-3-elver@google.com

Clang does not allow -fsanitize-coverage=trace-{pc,cmp} together
with -fsanitize=bounds or with ubsan:

  clang: error: argument unused during compilation: '-fsanitize-coverage=trace-pc' [-Werror,-Wunused-command-line-argument]
  clang: error: argument unused during compilation: '-fsanitize-coverage=trace-cmp' [-Werror,-Wunused-command-line-argument]

To avoid the warning, check whether clang can handle this correctly or
disallow ubsan and kcsan when kcov is enabled.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marco Elver <elver@google.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://bugs.llvm.org/show_bug.cgi?id=45831
Link: https://lore.kernel.org/lkml/20200505142341.1096942-1-arnd@arndb.de
Link: https://lkml.kernel.org/r/20200521142047.169334-2-elver@google.com

Merge the state of the locking kcsan branch before the read/write_once()
and the atomics modifications got merged.

Squash the fallout of the rebase on top of the read/write once and atomic
fallback work into the merge. The history of the original branch is
preserved in tag locking-kcsan-2020-06-02.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Currently instrumentation of atomic primitives is done at the architecture
level, while composites or fallbacks are provided at the generic level.

The result is that there are no uninstrumented variants of the
fallbacks. Since there is now need of such variants to isolate text poke
from any form of instrumentation invert this ordering.

Doing this means moving the instrumentation into the generic code as
well as having (for now) two variants of the fallbacks.

Notes:

 - the various *cond_read* primitives are not proper fallbacks
   and got moved into linux/atomic.c. No arch_ variants are
   generated because the base primitives smp_cond_load*()
   are instrumented.

 - once all architectures are moved over to arch_atomic_ one of the
   fallback variants can be removed and some 2300 lines reclaimed.

 - atomic_{read,set}*() are no longer double-instrumented
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lkml.kernel.org/r/20200505134058.769149955@linutronix.de

Use __always_inline for atomic fallback wrappers. When building for size
(CC_OPTIMIZE_FOR_SIZE), some compilers appear to be less inclined to
inline even relatively small static inline functions that are assumed to
be inlinable such as atomic ops. This can cause problems, for example in
UACCESS regions.

While the fallback wrappers aren't pure wrappers, they are trivial
nonetheless, and the function they wrap should determine the final
inlining policy.

For x86 tinyconfig we observe:
- vmlinux baseline: 1315988
- vmlinux with patch: 1315928 (-60 bytes)

[ tglx: Cherry-picked from KCSAN ]
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Pull epoll update from Al Viro:
 "epoll conversion to read_iter from Jens; I thought there might be more
  epoll stuff this cycle, but uaccess took too much time"

* 'work.epoll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  eventfd: convert to f_op->read_iter()

Pull vfs fixes from Al Viro:
 "A couple of trivial patches that fell through the cracks last cycle"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: fix indentation in deactivate_super()
  vfs: Remove duplicated d_mountpoint check in __is_local_mountpoint

Pull sysctl fixes from Al Viro:
 "Fixups to regressions in sysctl series"

* 'work.sysctl' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  sysctl: reject gigantic reads/write to sysctl files
  cdrom: fix an incorrect __user annotation on cdrom_sysctl_info
  trace: fix an incorrect __user annotation on stack_trace_sysctl
  random: fix an incorrect __user annotation on proc_do_entropy
  net/sysctl: remove leftover __user annotations on neigh_proc_dointvec*
  net/sysctl: use cpumask_parse in flow_limit_cpu_sysctl

Pull i915 uaccess updates from Al Viro:
 "Low-hanging fruit in i915; there are several trickier followups, but
  that'll wait for the next cycle"

* 'uaccess.i915' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  i915:get_engines(): get rid of pointless access_ok()
  i915: alloc_oa_regs(): get rid of pointless access_ok()
  i915 compat ioctl(): just use drm_ioctl_kernel()
  i915: switch copy_perf_config_registers_or_number() to unsafe_put_user()
  i915: switch query_{topology,engine}_info() to copy_to_user()

Pull misc uaccess updates from Al Viro:
 "Assorted uaccess patches for this cycle - the stuff that didn't fit
  into thematic series"

* 'uaccess.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  bpf: make bpf_check_uarg_tail_zero() use check_zeroed_user()
  x86: kvm_hv_set_msr(): use __put_user() instead of 32bit __clear_user()
  user_regset_copyout_zero(): use clear_user()
  TEST_ACCESS_OK _never_ had been checked anywhere
  x86: switch cp_stat64() to unsafe_put_user()
  binfmt_flat: don't use __put_user()
  binfmt_elf_fdpic: don't use __... uaccess primitives
  binfmt_elf: don't bother with __{put,copy_to}_user()
  pselect6() and friends: take handling the combined 6th/7th args into helper

Pull proc fix from Eric Biederman:
 "Syzbot found a NULL pointer dereference if kzalloc of s_fs_info fails"

* 'proc-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  proc: s_fs_info may be NULL when proc_kill_sb is called

Pull READ/WRITE_ONCE rework from Will Deacon:
 "This the READ_ONCE rework I've been working on for a while, which
  bumps the minimum GCC version and improves code-gen on arm64 when
  stack protector is enabled"

[ Side note: I'm _really_ tempted to raise the minimum gcc version to
  4.9, so that we can just say that we require _Generic() support.

  That would allow us to more cleanly handle a lot of the cases where we
  depend on very complex macros with 'sizeof' or __builtin_choose_expr()
  with __builtin_types_compatible_p() etc.

  This branch has a workaround for sparse not handling _Generic(),
  either, but that was already fixed in the sparse development branch,
  so it's really just gcc-4.9 that we'd require.   - Linus ]

* 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux:
  compiler_types.h: Use unoptimized __unqual_scalar_typeof for sparse
  compiler_types.h: Optimize __unqual_scalar_typeof compilation time
  compiler.h: Enforce that READ_ONCE_NOCHECK() access size is sizeof(long)
  compiler-types.h: Include naked type in __pick_integer_type() match
  READ_ONCE: Fix comment describing 2x32-bit atomicity
  gcov: Remove old GCC 3.4 support
  arm64: barrier: Use '__unqual_scalar_typeof' for acquire/release macros
  locking/barriers: Use '__unqual_scalar_typeof' for load-acquire macros
  READ_ONCE: Drop pointer qualifiers when reading from scalar types
  READ_ONCE: Enforce atomicity for {READ,WRITE}_ONCE() memory accesses
  READ_ONCE: Simplify implementations of {READ,WRITE}_ONCE()
  arm64: csum: Disable KASAN for do_csum()
  fault_inject: Don't rely on "return value" from WRITE_ONCE()
  net: tls: Avoid assigning 'const' pointer to non-const pointer
  netfilter: Avoid assigning 'const' pointer to non-const pointer
  compiler/gcc: Raise minimum GCC version for kernel builds to 4.8

Fixes: e05c7b1f ("mm: pgtable: add shortcuts for accessing kernel PMD and PTE")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Mike Rapoport <rppt@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull more documentation updates from Jonathan Corbet:
 "A handful of late-arriving docs fixes, along with a patch changing a
  lot of HTTP links to HTTPS that had to be yanked and redone before the
  first pull"

* tag 'docs-5.8-2' of git://git.lwn.net/linux:
  docs/memory-barriers.txt/kokr: smp_mb__{before,after}_atomic(): update Documentation
  Documentation: devres: add missing entry for devm_platform_get_and_ioremap_resource()
  Replace HTTP links with HTTPS ones: documentation
  docs: it_IT: address invalid reference warnings
  doc: zh_CN: use doc reference to resolve undefined label warning
  docs: Update the location of the LF NDA program
  docs: dev-tools: coccinelle: underlines

Pull more ACPI updates from Rafael Wysocki:
 "Update the ACPICA code in the kernel to upstream revision 20200528
  with the following changes:

   - Remove some dead code from the acpidump utility (Bob Moore)

   - Add new OperationRegion subtype keyword PlatformRtMechanism to the
     compiler (Erik Kaneda)"

* tag 'acpi-5.8-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPICA: Update version to 20200528
  ACPICA: iASL: add new OperationRegion subtype keyword PlatformRtMechanism
  ACPICA: acpidump: Removed dead code from oslinuxtbl.c

Pull more power management updates from Rafael Wysocki:
 "These are operating performance points (OPP) framework updates mostly,
  including support for interconnect bandwidth in the OPP core, plus a
  few cpufreq changes, including boost support in the CPPC cpufreq
  driver, an ACPI device power management fix and a hibernation code
  cleanup.

  Specifics:

   - Add support for interconnect bandwidth to the OPP core (Georgi
     Djakov, Saravana Kannan, Sibi Sankar, Viresh Kumar).

   - Add support for regulator enable/disable to the OPP core (Kamil
     Konieczny).

   - Add boost support to the CPPC cpufreq driver (Xiongfeng Wang).

   - Make the tegra186 cpufreq driver set the
     CPUFREQ_NEED_INITIAL_FREQ_CHECK flag (Mian Yousaf Kaukab).

   - Prevent the ACPI power management from using power resources with
     devices where the list of power resources for power state D0 (full
     power) is missing (Rafael Wysocki).

   - Annotate a hibernation-related function with __init (Christophe
     JAILLET)"

* tag 'pm-5.8-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: PM: Avoid using power resources if there are none for D0
  cpufreq: CPPC: add SW BOOST support
  cpufreq: change '.set_boost' to act on one policy
  PM: hibernate: Add __init annotation to swsusp_header_init()
  opp: Don't parse icc paths unnecessarily
  opp: Remove bandwidth votes when target_freq is zero
  opp: core: add regulators enable and disable
  opp: Reorder the code for !target_freq case
  opp: Expose bandwidth information via debugfs
  cpufreq: dt: Add support for interconnect bandwidth scaling
  opp: Update the bandwidth on OPP frequency changes
  opp: Add sanity checks in _read_opp_key()
  opp: Add support for parsing interconnect bandwidth
  cpufreq: tegra186: add CPUFREQ_NEED_INITIAL_FREQ_CHECK flag
  OPP: Add helpers for reading the binding properties
  dt-bindings: opp: Introduce opp-peak-kBps and opp-avg-kBps bindings

Pull input updates from Dmitry Torokhov:

 - a new driver for the Azoteq IQS269A capacitive touch controller

 - a new driver for the Cypress CY8CTMA140 touchscreen

 - updates to Elan and ft5x06 touchscreen drivers

 - assorted driver fixes

 - msm-vibrator has been removed as we have a more generic solution

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (28 commits)
  Input: adi - work around module name confict
  Input: iqs269a - add missing I2C dependency
  Input: elants - refactor elants_i2c_execute_command()
  Input: elants - override touchscreen info with DT properties
  Input: elants - remove unused axes
  Input: add support for Azoteq IQS269A
  dt-bindings: input: Add bindings for Azoteq IQS269A
  Input: imx_sc_key - use devm_add_action_or_reset() to handle all cleanups
  Input: remove msm-vibrator driver
  dt-bindings: Input: remove msm-vibrator
  Input: elants_i2c - provide an attribute to show calibration count
  Input: introduce input_mt_report_slot_inactive()
  dt-bindings: input: touchscreen: elants_i2c: convert to YAML
  Input: add driver for the Cypress CY8CTMA140 touchscreen
  dt-bindings: touchscreen: Add CY8CTMA140 bindings
  Input: edt-ft5x06 - prefer asynchronous probe
  Input: edt-ft5x06 - improve power management operations
  Input: edt-ft5x06 - move parameter restore into helper
  Input: edt-ft5x06 - fix get_default register write access
  Input: atkbd - receive and use physcode->keycode mapping from FW
  ...

Pull virtio updates from Michael Tsirkin:

 - virtio-mem: paravirtualized memory hotplug

 - support doorbell mapping for vdpa

 - config interrupt support in ifc

 - fixes all over the place

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (40 commits)
  vhost/test: fix up after API change
  virtio_mem: convert device block size into 64bit
  virtio-mem: drop unnecessary initialization
  ifcvf: implement config interrupt in IFCVF
  vhost: replace -1 with VHOST_FILE_UNBIND in ioctls
  vhost_vdpa: Support config interrupt in vdpa
  ifcvf: ignore continuous setting same status value
  virtio-mem: Don't rely on implicit compiler padding for requests
  virtio-mem: Try to unplug the complete online memory block first
  virtio-mem: Use -ETXTBSY as error code if the device is busy
  virtio-mem: Unplug subblocks right-to-left
  virtio-mem: Drop manual check for already present memory
  virtio-mem: Add parent resource for all added "System RAM"
  virtio-mem: Better retry handling
  virtio-mem: Offline and remove completely unplugged memory blocks
  mm/memory_hotplug: Introduce offline_and_remove_memory()
  virtio-mem: Allow to offline partially unplugged memory blocks
  mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINE
  virtio-mem: Paravirtualized memory hotunplug part 2
  virtio-mem: Paravirtualized memory hotunplug part 1
  ...

Pull UML updates from Richard Weinberger:

 - Use fdatasync() in ubd

 - Add a generic "fd" vector transport

 - Minor cleanups and fixes

* tag 'for-linus-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
  um: virtio: Replace zero-length array with flexible-array
  um: Use fdatasync() when mapping the UBD FSYNC command
  um: Do not evaluate compiler's library path when cleaning
  um: Neaten vu_err macro definition
  um: Add a generic "fd" vector transport
  um: Add include: memset() and memcpy() are in <string.h>

Pull UBI update from Richard Weinberger:
 "This contains a single change for UBI:

   - Select fastmap anchor PEBs considering wear level rules"

* tag 'for-linus-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
  ubi: Select fastmap anchor PEBs considering wear level rules

Pull MTD updates from Richard Weinberger:
 "MTD core changes:
   - partition parser: Support MTD names containing one or more colons.
   - mtdblock: clear cache_state to avoid writing to bad blocks
     repeatedly.

  Raw NAND core changes:
   - Stop using nand_release(), patched all drivers.
   - Give more information about the ECC weakness when not matching the
     chip's requirement.
   - MAINTAINERS updates.
   - Support emulated SLC mode on MLC NANDs.
   - Support "constrained" controllers, adapt the core and ONFI/JEDEC
     table parsing and Micron's code.
   - Take check_only into account.
   - Add an invalid ECC mode to discriminate with valid ones.
   - Return an enum from of_get_nand_ecc_algo().
   - Drop OOB_FIRST placement scheme.
   - Introduce nand_extract_bits().
   - Ensure a consistent bitflips numbering.
   - BCH lib:
      - Allow easy bit swapping.
      - Rework a little bit the exported function names.
   - Fix nand_gpio_waitrdy().
   - Propage CS selection to sub operations.
   - Add a NAND_NO_BBM_QUIRK flag.
   - Give the possibility to verify a read operation is supported.
   - Add a helper to check supported operations.
   - Avoid indirect access to ->data_buf().
   - Rename the use_bufpoi variables.
   - Fix comments about the use of bufpoi.
   - Rename a NAND chip option.
   - Reorder the nand_chip->options flags.
   - Translate obscure bitfields into readable macros.
   - Timings:
      - Fix default values.
      - Add mode information to the timings structure.

  Raw NAND controller driver changes:
   - Fixed many error paths.
   - Arasan
      - New driver
   - Au1550nd:
      - Various cleanups
      - Migration to ->exec_op()
   - brcmnand:
      - Misc cleanup.
      - Support v2.1-v2.2 controllers.
      - Remove unused including <linux/version.h>.
      - Correctly verify erased pages.
      - Fix Hamming OOB layout.
   - Cadence
      - Make cadence_nand_attach_chip static.
   - Cafe:
      - Set the NAND_NO_BBM_QUIRK flag
   - cmx270:
      - Remove this controller driver.
   - cs553x:
      - Misc cleanup
      - Migration to ->exec_op()
   - Davinci:
      - Misc cleanup.
      - Migration to ->exec_op()
   - Denali:
      - Add more delays before latching incoming data
   - Diskonchip:
      - Misc cleanup
      - Migration to ->exec_op()
   - Fsmc:
      - Change to non-atomic bit operations.
   - GPMI:
      - Use nand_extract_bits()
      - Fix runtime PM imbalance.
   - Ingenic:
      - Migration to exec_op()
      - Fix the RB gpio active-high property on qi, lb60
      - Make qi_lb60_ooblayout_ops static.
   - Marvell:
      - Misc cleanup and small fixes
   - Nandsim:
      - Fix the error paths, driver wide.
   - Omap_elm:
      - Fix runtime PM imbalance.
   - STM32_FMC2:
      - Misc cleanups (error cases, comments, timeout valus, cosmetic
        changes).

  SPI NOR core changes:
   - Add, update support and fix few flashes.
   - Prepare BFPT parsing for JESD216 rev D.
   - Kernel doc fixes.

  CFI changes:
   - Support the absence of protection registers for Intel CFI flashes.
   - Replace zero-length array with flexible-arrays"

* tag 'mtd/for-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (208 commits)
  mtd: clear cache_state to avoid writing to bad blocks repeatedly
  mtd: parser: cmdline: Support MTD names containing one or more colons
  mtd: physmap_of_gemini: remove defined but not used symbol 'syscon_match'
  mtd: rawnand: Add an invalid ECC mode to discriminate with valid ones
  mtd: rawnand: Return an enum from of_get_nand_ecc_algo()
  mtd: rawnand: Drop OOB_FIRST placement scheme
  mtd: rawnand: Avoid a typedef
  mtd: Fix typo in mtd_ooblayout_set_databytes() description
  mtd: rawnand: Stop using nand_release()
  mtd: rawnand: nandsim: Reorganize ns_cleanup_module()
  mtd: rawnand: nandsim: Rename a label in ns_init_module()
  mtd: rawnand: nandsim: Manage lists on error in ns_init_module()
  mtd: rawnand: nandsim: Fix the label pointing on nand_cleanup()
  mtd: rawnand: nandsim: Free erase_block_wear on error
  mtd: rawnand: nandsim: Use an additional label when freeing the nandsim object
  mtd: rawnand: nandsim: Stop using nand_release()
  mtd: rawnand: nandsim: Free the partition names in ns_free()
  mtd: rawnand: nandsim: Free the allocated device on error in ns_init()
  mtd: rawnand: nandsim: Free partition names on error in ns_init()
  mtd: rawnand: nandsim: Fix the two ns_alloc_device() error paths
  ...

syzbot found that proc_fill_super() fails before filling up sb->s_fs_info,
deactivate_locked_super() will be called and sb->s_fs_info will be NULL.
The proc_kill_sb() does not expect fs_info to be NULL which is wrong.

Link: https://lore.kernel.org/lkml/0000000000002d7ca605a7b8b1c5@google.com
Reported-by: syzbot+4abac52934a48af5ff19@syzkaller.appspotmail.com
Fixes: fa10fed3 ("proc: allow to mount many instances of proc in one pid namespace")
Signed-off-by: Alexey Gladkov <gladkov.alexey@gmail.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

Pull clk updates from Stephen Boyd:
 "This time around we have four lines of diff in the core framework,
  removing a function that isn't used anymore. Otherwise the main new
  thing for the common clk framework is that it is selectable in the
  Kconfig language now. Hopefully this will let clk drivers and clk
  consumers be testable on more than the architectures that support the
  clk framework. The goal is to introduce some Kunit tests for the
  framework.

  Outside of the core framework we have the usual set of various driver
  updates and non-critical fixes. The dirstat shows that the new
  Baikal-T1 driver is the largest addition this time around in terms of
  lines of code. After that the x86 (Intel), Qualcomm, and Mediatek
  drivers introduce many lines to support new or upcoming SoCs. After
  that the dirstat shows the usual suspects working on their SoC support
  by fixing minor bugs, correcting data and converting some of their DT
  bindings to YAML.

  Core:
   - Allow the COMMON_CLK config to be selectable

  New Drivers:
   - Clk driver for Baikal-T1 SoCs
   - Mediatek MT6765 clock support
   - Support for Intel Agilex clks
   - Add support for X1830 and X1000 Ingenic SoC clk controllers
   - Add support for the new Renesas RZ/G1H (R8A7742) SoC
   - Add support for Qualcomm's MSM8939 Generic Clock Controller

  Updates:
   - Support IDT VersaClock 5P49V5925
   - Bunch of updates for HSDK clock generation unit (CGU) driver
   - Start making audio and GPU clks work on Marvell MMP2/MMP3 SoCs
   - Add some GPU, NPU, and UFS clks to Qualcomm SM8150 driver
   - Enable supply regulators for GPU gdscs on Qualcomm SoCs
   - Add support for Si5342, Si5344 and Si5345 chips
   - Support custom flags in Xilinx zynq firmware
   - Various small fixes to the Xilinx clk driver
   - A single minor rounding fix for the legacy Allwinner clock support
   - A few patches from Abel Vesa as preparation of adding audiomix
     clock support on i.MX
   - A couple of cleanups from Anson Huang for i.MX clk-sscg-pll and
     clk-pllv3 drivers
   - Drop dependency on ARM64 for i.MX8M clock driver, to support
     aarch32 mode on aarch64 hardware
   - A series from Peng Fan to improve i.MX8M clock drivers, using
     composite clock for core and bus clk slice
   - Set a better parent clock for flexcan on i.MX6UL to support CiA102
     defined bit rates
   - A couple changes for EMC frequency scaling on Tegra210
   - Support for CPU frequency scaling on Tegra20/Tegra30
   - New clk gate for CSI test pattern generator on Tegra210
   - Regression fixes for Samsung exynos542x and exynos5433 SoCs
   - Use of fallthrough; attribute for Samsung s3c24xx
   - Updates and fixup HDMI and video clocks on Meson8b
   - Fixup reset polarity on Meson8b
   - Fix GPU glitch free mux switch on Meson gx and g12
   - A minor fix for the currently unused suspend/resume handling on
     Renesas RZ/A1 and RZ/A2
   - Two more conversions of Renesas DT bindings to json-schema
   - Add support for the USB 2.0 clock selector on Renesas R-Car M3-W+"

* tag 'clk-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux: (155 commits)
  clk: mediatek: Remove ifr{0,1}_cfg_regs structures
  clk: baikal-t1: remove redundant assignment to variable 'divider'
  clk: baikal-t1: fix spelling mistake "Uncompatible" -> "Incompatible"
  dt-bindings: clock: Add a missing include to MMP Audio Clock binding
  dt: Add bindings for IDT VersaClock 5P49V5925
  clk: vc5: Add support for IDT VersaClock 5P49V6965
  clk: Add Baikal-T1 CCU Dividers driver
  clk: Add Baikal-T1 CCU PLLs driver
  dt-bindings: clk: Add Baikal-T1 CCU Dividers binding
  dt-bindings: clk: Add Baikal-T1 CCU PLLs binding
  clk: mediatek: assign the initial value to clk_init_data of mtk_mux
  clk: mediatek: Add MT6765 clock support
  clk: mediatek: add mt6765 clock IDs
  dt-bindings: clock: mediatek: document clk bindings vcodecsys for Mediatek MT6765 SoC
  dt-bindings: clock: mediatek: document clk bindings mipi0a for Mediatek MT6765 SoC
  dt-bindings: clock: mediatek: document clk bindings for Mediatek MT6765 SoC
  CLK: HSDK: CGU: add support for 148.5MHz clock
  CLK: HSDK: CGU: support PLL bypassing
  CLK: HSDK: CGU: check if PLL is bypassed first
  clk: clk-si5341: Add support for the Si5345 series
  ...

Pull power supply and reset updates from Sebastian Reichel:
 "This time there are lots of changes. Quite a few changes to the core,
  lots of driver changes and one change to kobject core (with Ack from
  Greg).

  Summary:

  kobject:
   - Increase number of allowed uevent variables

  power-supply core:
   - Add power-supply type in uevent
   - Cleanup property handling in core
   - Make property and usb_type pointers const
   - Convert core power-supply DT binding to YAML
   - Cleanup HWMON code
   - Add new health status "calibration required"
   - Add new properties for manufacture date and capacity error margin

  battery drivers:
   - new cw2015 battery driver used by pine64 Pinebook Pro laptop
   - axp22: blacklist on Meegopad T02
   - sc27xx: support current/voltage reading
   - max17042: support time-to-empty reading
   - simple-battery: add more battery parameters
   - bq27xxx: convert DT binding document to YAML
   - sbs-battery: add TI BQ20Z65 support, fix technology property,
         convert DT binding to YAML, add option to disable charger
         broadcasts, add new properties: manufacture date, capacity
         error margin, average current, charge current and voltage and
         support calibration required health status
   - misc fixes

  charger drivers:
   - bq25890: cleanup, implement charge type, precharge current and
         input current limiting properties
   - bd70528: use new linear range helper library
   - bd99954: new charger driver
   - mp2629: new charger driver
   - misc fixes

  reboot drivers:
   - oxnas-restart: introduce new driver
   - syscon-reboot: convert DT binding to YAML, add parent syscon device
         support
   - misc fixes"

* tag 'for-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/sre/linux-power-supply: (85 commits)
  power: supply: cw2015: Attach OF ID table to the driver
  power: reset: gpio-poweroff: add missing '\n' in dev_err()
  Revert "power: supply: sbs-battery: simplify read_read_string_data"
  Revert "power: supply: sbs-battery: add PEC support"
  dt-bindings: power: sbs-battery: Convert to yaml
  power: supply: sbs-battery: constify power-supply property array
  power: supply: sbs-battery: switch to i2c's probe_new
  power: supply: sbs-battery: switch from of_property_* to device_property_*
  power: supply: sbs-battery: add ability to disable charger broadcasts
  power: supply: sbs-battery: fix idle battery status
  power: supply: sbs-battery: add POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED support
  power: supply: sbs-battery: add MANUFACTURE_DATE support
  power: supply: sbs-battery: add POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT/VOLTAGE_MAX support
  power: supply: sbs-battery: Improve POWER_SUPPLY_PROP_TECHNOLOGY support
  power: supply: sbs-battery: add POWER_SUPPLY_PROP_CURRENT_AVG support
  power: supply: sbs-battery: add PEC support
  power: supply: sbs-battery: simplify read_read_string_data
  power: supply: sbs-battery: add POWER_SUPPLY_PROP_CAPACITY_ERROR_MARGIN support
  power: supply: sbs-battery: Add TI BQ20Z65 support
  power: supply: core: add POWER_SUPPLY_HEALTH_CALIBRATION_REQUIRED
  ...

Instead of triggering a WARN_ON deep down in the page allocator just
give up early on allocations that are way larger than the usual sysctl
values.

Fixes: 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

No user pointers for sysctls anymore.

Fixes: 32927393 ("sysctl: pass kernel pointers to ->proc_handler")
Reported-by: build test robot <lkp@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

Pull dmaengine updates from Vinod Koul:
 "A fairly small dmaengine update which includes mostly driver updates
  (dmatest, dw-edma, ioat, mmp-tdma and k3-udma) along with Renesas
  binding update to json-schema"

* tag 'dmaengine-5.8-rc1' of git://git.infradead.org/users/vkoul/slave-dma: (39 commits)
  dmaengine: imx-sdma: initialize all script addresses
  dmaengine: ti: k3-udma: Use proper return code in alloc_chan_resources
  dmaengine: ti: k3-udma: Remove udma_chan.in_ring_cnt
  dmaengine: ti: k3-udma: Add missing dma_sync call for rx flush descriptor
  dmaengine: at_xdmac: Replace zero-length array with flexible-array
  dmaengine: at_hdmac: Replace zero-length array with flexible-array
  dmaengine: qcom: bam_dma: Replace zero-length array with flexible-array
  dmaengine: ti: k3-udma: Use PTR_ERR_OR_ZERO() to simplify code
  dmaengine: moxart-dma: Drop pointless static qualifier in moxart_probe()
  dmaengine: sf-pdma: Simplify the error handling path in 'sf_pdma_probe()'
  dmaengine: qcom_hidma: use true,false for bool variable
  dmaengine: dw-edma: support local dma device transfer semantics
  dmaengine: Fix doc strings to satisfy validation script
  dmaengine: Include dmaengine.h into dmaengine.c
  dmaengine: dmatest: Describe members of struct dmatest_info
  dmaengine: dmatest: Describe members of struct dmatest_params
  dmaengine: dmatest: Allow negative timeout value to specify infinite wait
  Revert "dmaengine: dmatest: timeout value of -1 should specify infinite wait"
  dmaengine: stm32-dma: direct mode support through device tree
  dt-bindings: dma: add direct mode support through device tree in stm32-dma
  ...

The improved paragraph about line lengths contains a sentence with a
duplicate word: there is one "are" at the end of a line, followed by a
second one at the beginning of the next line.

Drop the first one, as that one is part of the longest line.

Fixes: bdc48fa1 ("checkpatch/coding-style: deprecate 80-column warning")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

"mm: consolidate pte_index() and pte_offset_*() definitions" was supposed
to remove arch/sparc/mm/srmmu.c:pte_offset_kernel().

Fixes: 974b9b2c ("mm: consolidate pte_index() and pte_offset_*() definitions")
Reported-by: kernel test robot <lkp@intel.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* acpica:
  ACPICA: Update version to 20200528
  ACPICA: iASL: add new OperationRegion subtype keyword PlatformRtMechanism
  ACPICA: acpidump: Removed dead code from oslinuxtbl.c

* pm-cpufreq:
  cpufreq: CPPC: add SW BOOST support
  cpufreq: change '.set_boost' to act on one policy
  cpufreq: tegra186: add CPUFREQ_NEED_INITIAL_FREQ_CHECK flag

* pm-acpi:
  ACPI: PM: Avoid using power resources if there are none for D0

* pm-opp:
  opp: Don't parse icc paths unnecessarily
  opp: Remove bandwidth votes when target_freq is zero
  opp: core: add regulators enable and disable
  opp: Reorder the code for !target_freq case
  opp: Expose bandwidth information via debugfs
  cpufreq: dt: Add support for interconnect bandwidth scaling
  opp: Update the bandwidth on OPP frequency changes
  opp: Add sanity checks in _read_opp_key()
  opp: Add support for parsing interconnect bandwidth
  interconnect: Remove unused module exit code from core
  interconnect: Disallow interconnect core to be built as a module
  interconnect: Add of_icc_get_by_index() helper function
  OPP: Add helpers for reading the binding properties
  dt-bindings: opp: Introduce opp-peak-kBps and opp-avg-kBps bindings

Pull fuse updates from Miklos Szeredi:

 - Fix a rare deadlock in virtiofs

 - Fix st_blocks in writeback cache mode

 - Fix wrong checks in splice move causing spurious warnings

 - Fix a race between a GETATTR request and a FUSE_NOTIFY_INVAL_INODE
   notification

 - Use rb-tree instead of linear search for pages currently under
   writeout by userspace

 - Fix copy_file_range() inconsistencies

* tag 'fuse-update-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: copy_file_range should truncate cache
  fuse: fix copy_file_range cache issues
  fuse: optimize writepages search
  fuse: update attr_version counter on fuse_notify_inval_inode()
  fuse: don't check refcount after stealing page
  fuse: fix weird page warning
  fuse: use dump_page
  virtiofs: do not use fuse_fill_super_common() for device installation
  fuse: always allow query of st_dev
  fuse: always flush dirty data on close(2)
  fuse: invalidate inode attr in writeback cache mode
  fuse: Update stale comment in queue_interrupt()
  fuse: BUG_ON correction in fuse_dev_splice_write()
  virtiofs: Add mount option and atime behavior to the doc
  virtiofs: schedule blocking async replies in separate worker

Pull overlayfs updates from Miklos Szeredi:
 "Fixes:

   - Resolve mount option conflicts consistently

   - Sync before remount R/O

   - Fix file handle encoding corner cases

   - Fix metacopy related issues

   - Fix an unintialized return value

   - Add missing permission checks for underlying layers

  Optimizations:

   - Allow multipe whiteouts to share an inode

   - Optimize small writes by inheriting SB_NOSEC from upper layer

   - Do not call ->syncfs() multiple times for sync(2)

   - Do not cache negative lookups on upper layer

   - Make private internal mounts longterm"

* tag 'ovl-update-5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs: (27 commits)
  ovl: remove unnecessary lock check
  ovl: make oip->index bool
  ovl: only pass ->ki_flags to ovl_iocb_to_rwf()
  ovl: make private mounts longterm
  ovl: get rid of redundant members in struct ovl_fs
  ovl: add accessor for ofs->upper_mnt
  ovl: initialize error in ovl_copy_xattr
  ovl: drop negative dentry in upper layer
  ovl: check permission to open real file
  ovl: call secutiry hook in ovl_real_ioctl()
  ovl: verify permissions in ovl_path_open()
  ovl: switch to mounter creds in readdir
  ovl: pass correct flags for opening real directory
  ovl: fix redirect traversal on metacopy dentries
  ovl: initialize OVL_UPPERDATA in ovl_lookup()
  ovl: use only uppermetacopy state in ovl_lookup()
  ovl: simplify setting of origin for index lookup
  ovl: fix out of bounds access warning in ovl_check_fb_len()
  ovl: return required buffer size for file handles
  ovl: sync dirty data when remounting to ro mode
  ...

Pull AFS fixes from David Howells:
 "A set of small patches to fix some things, most of them minor.

   - Fix a memory leak in afs_put_sysnames()

   - Fix an oops in AFS file locking

   - Fix new use of BUG()

   - Fix debugging statements containing %px

   - Remove afs_zero_fid as it's unused

   - Make afs_zap_data() static"

* tag 'afs-fixes-20200609' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Make afs_zap_data() static
  afs: Remove afs_zero_fid as it's not used
  afs: Fix debugging statements with %px to be %p
  afs: Fix use of BUG()
  afs: Fix file locking
  afs: Fix memory leak in afs_put_sysnames()