Merge tag 'v5.10-rc1' into spi-5.10

Linux 5.10-rc1

Merge tag 'v5.10-rc1' into asoc-5.10

Linux 5.10-rc1

asm-generic/atomic: Add try_cmpxchg() fallbacks

Only x86 provides try_cmpxchg() outside of the atomic_t interfaces,
provide generic fallbacks to create this interface from the widely
available cmpxc

asm-generic/atomic: Add try_cmpxchg() fallbacks

Only x86 provides try_cmpxchg() outside of the atomic_t interfaces,
provide generic fallbacks to create this interface from the widely
available cmpxchg() function.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/159870621515.1229682.15506193091065001742.stgit@devnote2

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Merge tag 'locking-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
"These are the locking updates for v5.10:

- Add deadlock dete

Merge tag 'locking-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull locking updates from Ingo Molnar:
"These are the locking updates for v5.10:

- Add deadlock detection for recursive read-locks.

The rationale is outlined in commit 224ec489d3cd ("lockdep/
Documention: Recursive read lock detection reasoning")

The main deadlock pattern we want to detect is:

TASK A: TASK B:

read_lock(X);
write_lock(X);
read_lock_2(X);

- Add "latch sequence counters" (seqcount_latch_t):

A sequence counter variant where the counter even/odd value is used
to switch between two copies of protected data. This allows the
read path, typically NMIs, to safely interrupt the write side
critical section.

We utilize this new variant for sched-clock, and to make x86 TSC
handling safer.

- Other seqlock cleanups, fixes and enhancements

- KCSAN updates

- LKMM updates

- Misc updates, cleanups and fixes"

* tag 'locking-core-2020-10-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (67 commits)
lockdep: Revert "lockdep: Use raw_cpu_*() for per-cpu variables"
lockdep: Fix lockdep recursion
lockdep: Fix usage_traceoverflow
locking/atomics: Check atomic-arch-fallback.h too
locking/seqlock: Tweak DEFINE_SEQLOCK() kernel doc
lockdep: Optimize the memory usage of circular queue
seqlock: Unbreak lockdep
seqlock: PREEMPT_RT: Do not starve seqlock_t writers
seqlock: seqcount_LOCKNAME_t: Introduce PREEMPT_RT support
seqlock: seqcount_t: Implement all read APIs as statement expressions
seqlock: Use unique prefix for seqcount_t property accessors
seqlock: seqcount_LOCKNAME_t: Standardize naming convention
seqlock: seqcount latch APIs: Only allow seqcount_latch_t
rbtree_latch: Use seqcount_latch_t
x86/tsc: Use seqcount_latch_t
timekeeping: Use seqcount_latch_t
time/sched_clock: Use seqcount_latch_t
seqlock: Introduce seqcount_latch_t
mm/swap: Do not abuse the seqcount_t latching API
time/sched_clock: Use raw_read_seqcount_latch() during suspend
...

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Merge branch 'kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core

Pull KCSAN updates for v5.10 from Paul E. McKenney:

- Improve kernel messages.

- Be more

Merge branch 'kcsan' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/core

Pull KCSAN updates for v5.10 from Paul E. McKenney:

- Improve kernel messages.

- Be more permissive with bitops races under KCSAN_ASSUME_PLAIN_WRITES_ATOMIC=y.

- Optimize debugfs stat counters.

- Introduce the instrument_*read_write() annotations, to provide a
finer description of certain ops - using KCSAN's compound instrumentation.
Use them for atomic RNW and bitops, where appropriate.
Doing this might find new races.
(Depends on the compiler having tsan-compound-read-before-write=1 support.)

- Support atomic built-ins, which will help certain architectures, such as s390.

- Misc enhancements and smaller fixes.

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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Merge branch 'master' into for-next

Sync with Linus' branch in order to be able to apply fixups
of more recent patches.

locking/atomics: Use read-write instrumentation for atomic RMWs

Use instrument_atomic_read_write() for atomic RMW ops.

Cc: Will Deacon <will@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Ar

locking/atomics: Use read-write instrumentation for atomic RMWs

Use instrument_atomic_read_write() for atomic RMW ops.

Cc: Will Deacon <will@kernel.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: <linux-arch@vger.kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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Merge branch 'for-next' into for-linus

Merge tag 'irqchip-fixes-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent

Pull irqchip fixes from Marc Zyngier:

- Fix atomicity of affinity update in the G

Merge tag 'irqchip-fixes-5.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/urgent

Pull irqchip fixes from Marc Zyngier:

- Fix atomicity of affinity update in the GIC driver
- Don't sleep in atomic when waiting for a GICv4.1 RD to respond
- Fix a couple of typos in user-visible messages

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Merge tag 'v5.8-rc3' into arm/qcom

Linux 5.8-rc3

Backmerge remote-tracking branch 'drm/drm-next' into drm-misc-next

Some conflicts with ttm_bo->offset removal, but drm-misc-next needs updating to v5.8.

Signed-off-by: Maarten Lankhorst <maarten.la

Backmerge remote-tracking branch 'drm/drm-next' into drm-misc-next

Some conflicts with ttm_bo->offset removal, but drm-misc-next needs updating to v5.8.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

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Merge drm/drm-next into drm-intel-next-queued

Catch up with upstream, in particular to get c1e8d7c6a7a6 ("mmap locking
API: convert mmap_sem comments").

Signed-off-by: Jani Nikula <jani.nikula@inte

Merge drm/drm-next into drm-intel-next-queued

Catch up with upstream, in particular to get c1e8d7c6a7a6 ("mmap locking
API: convert mmap_sem comments").

Signed-off-by: Jani Nikula <jani.nikula@intel.com>

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Merge remote-tracking branch 'torvalds/master' into perf/urgent

To get some newer headers that got out of sync with the copies in tools/
so that we can try to have the tools/perf/ build clean for v5

Merge remote-tracking branch 'torvalds/master' into perf/urgent

To get some newer headers that got out of sync with the copies in tools/
so that we can try to have the tools/perf/ build clean for v5.8 with
fewer pull requests.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

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Merge tag 'v5.8-rc1' into regulator-5.8

Linux 5.8-rc1

Merge tag 'v5.8-rc1' into fixes

Linux 5.8-rc1

Merge v5.8-rc1 into drm-misc-fixes

Beginning a new release cycles for what will become v5.8. Updating
drm-misc-fixes accordingly.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>

Merge tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull the Kernel Concurrency Sanitizer from Thomas Gleixner:
"The Kernel Concurrency Sanitizer (KCSAN) i

Merge tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull the Kernel Concurrency Sanitizer from Thomas Gleixner:
"The Kernel Concurrency Sanitizer (KCSAN) is a dynamic race detector,
which relies on compile-time instrumentation, and uses a
watchpoint-based sampling approach to detect races.

The feature was under development for quite some time and has already
found legitimate bugs.

Unfortunately it comes with a limitation, which was only understood
late in the development cycle:

It requires an up to date CLANG-11 compiler

CLANG-11 is not yet released (scheduled for June), but it's the only
compiler today which handles the kernel requirements and especially
the annotations of functions to exclude them from KCSAN
instrumentation correctly.

These annotations really need to work so that low level entry code and
especially int3 text poke handling can be completely isolated.

A detailed discussion of the requirements and compiler issues can be
found here:

https://lore.kernel.org/lkml/CANpmjNMTsY_8241bS7=XAfqvZHFLrVEkv_uM4aDUWE_kh3Rvbw@mail.gmail.com/

We came to the conclusion that trying to work around compiler
limitations and bugs again would end up in a major trainwreck, so
requiring a working compiler seemed to be the best choice.

For Continous Integration purposes the compiler restriction is
manageable and that's where most xxSAN reports come from.

For a change this limitation might make GCC people actually look at
their bugs. Some issues with CSAN in GCC are 7 years old and one has
been 'fixed' 3 years ago with a half baken solution which 'solved' the
reported issue but not the underlying problem.

The KCSAN developers also ponder to use a GCC plugin to become
independent, but that's not something which will show up in a few
days.

Blocking KCSAN until wide spread compiler support is available is not
a really good alternative because the continuous growth of lockless
optimizations in the kernel demands proper tooling support"

* tag 'locking-kcsan-2020-06-11' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (76 commits)
compiler_types.h, kasan: Use __SANITIZE_ADDRESS__ instead of CONFIG_KASAN to decide inlining
compiler.h: Move function attributes to compiler_types.h
compiler.h: Avoid nested statement expression in data_race()
compiler.h: Remove data_race() and unnecessary checks from {READ,WRITE}_ONCE()
kcsan: Update Documentation to change supported compilers
kcsan: Remove 'noinline' from __no_kcsan_or_inline
kcsan: Pass option tsan-instrument-read-before-write to Clang
kcsan: Support distinguishing volatile accesses
kcsan: Restrict supported compilers
kcsan: Avoid inserting __tsan_func_entry/exit if possible
ubsan, kcsan: Don't combine sanitizer with kcov on clang
objtool, kcsan: Add kcsan_disable_current() and kcsan_enable_current_nowarn()
kcsan: Add __kcsan_{enable,disable}_current() variants
checkpatch: Warn about data_race() without comment
kcsan: Use GFP_ATOMIC under spin lock
Improve KCSAN documentation a bit
kcsan: Make reporting aware of KCSAN tests
kcsan: Fix function matching in report
kcsan: Change data_race() to no longer require marking racing accesses
kcsan: Move kcsan_{disable,enable}_current() to kcsan-checks.h
...

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Rebase locking/kcsan to locking/urgent

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

Rebase locking/kcsan to locking/urgent

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>

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asm-generic, atomic-instrumented: Use generic instrumented.h

This switches atomic-instrumented.h to use the generic instrumentation
wrappers provided by instrumented.h.

No functional change intende

asm-generic, atomic-instrumented: Use generic instrumented.h

This switches atomic-instrumented.h to use the generic instrumentation
wrappers provided by instrumented.h.

No functional change intended.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

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Merge branch 'kcsan.2020.01.07a' into locking/kcsan

Pull KCSAN updates from Paul E. McKenney:

- UBSAN fixes
- inlining updates
- documentation updates

Signed-off-by: Ingo Molnar <mingo@kernel.o

Merge branch 'kcsan.2020.01.07a' into locking/kcsan

Pull KCSAN updates from Paul E. McKenney:

- UBSAN fixes
- inlining updates
- documentation updates

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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asm-generic/atomic: Use __always_inline for pure wrappers

Prefer __always_inline for atomic wrappers. When building for size
(CC_OPTIMIZE_FOR_SIZE), some compilers appear to be less inclined to
inli

asm-generic/atomic: Use __always_inline for pure wrappers

Prefer __always_inline for atomic 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.

By using __always_inline, we let the real implementation and not the
wrapper determine the final inlining preference.

For x86 tinyconfig we observe:
- vmlinux baseline: 1316204
- vmlinux with patch: 1315988 (-216 bytes)

This came up when addressing UACCESS warnings with CC_OPTIMIZE_FOR_SIZE
in the KCSAN runtime:
http://lkml.kernel.org/r/58708908-84a0-0a81-a836-ad97e33dbb62@infradead.org

Reported-by: Randy Dunlap <rdunlap@infradead.org>
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>

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Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/kcsan

Pull the KCSAN subsystem from Paul E. McKenney:

"This pull request contains base ke

Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into locking/kcsan

Pull the KCSAN subsystem from Paul E. McKenney:

"This pull request contains base kernel concurrency sanitizer
(KCSAN) enablement for x86, courtesy of Marco Elver. KCSAN is a
sampling watchpoint-based data-race detector, and is documented in
Documentation/dev-tools/kcsan.rst. KCSAN was announced in September,
and much feedback has since been incorporated:

http://lkml.kernel.org/r/CANpmjNPJ_bHjfLZCAPV23AXFfiPiyXXqqu72n6TgWzb2Gnu1eA@mail.gmail.com

The data races located thus far have resulted in a number of fixes:

https://github.com/google/ktsan/wiki/KCSAN#upstream-fixes-of-data-races-found-by-kcsan

Additional information may be found here:

https://lore.kernel.org/lkml/20191114180303.66955-1-elver@google.com/
"

Signed-off-by: Ingo Molnar <mingo@kernel.org>

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locking/atomics, kcsan: Add KCSAN instrumentation

This adds KCSAN instrumentation to atomic-instrumented.h.

Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm

locking/atomics, kcsan: Add KCSAN instrumentation

This adds KCSAN instrumentation to atomic-instrumented.h.

Signed-off-by: Marco Elver <elver@google.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

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Merge branch 'next' into for-linus

Prepare input updates for 5.3 merge window.

Merge tag 'v5.1' into next

Sync up with mainline to bring in the latest APIs.