Commit 7add7875 authored by Ingo Molnar's avatar Ingo Molnar
Browse files

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: default avatarIngo Molnar <mingo@kernel.org>
parents 837171fe e33f9a16

Documentation/dev-tools/kcsan.rst

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@@ -101,18 +101,28 @@ instrumentation or e.g. DMA accesses. 
Selective analysis

Selective analysis

~~~~~~~~~~~~~~~~~~

~~~~~~~~~~~~~~~~~~





To disable KCSAN data race detection for an entire subsystem, add to the

It may be desirable to disable data race detection for specific accesses,

respective ``Makefile``::

functions, compilation units, or entire subsystems.  For static blacklisting,

the below options are available:





    KCSAN_SANITIZE := n

* KCSAN understands the ``data_race(expr)`` annotation, which tells KCSAN that

  any data races due to accesses in ``expr`` should be ignored and resulting

  behaviour when encountering a data race is deemed safe.



* Disabling data race detection for entire functions can be accomplished by

  using the function attribute ``__no_kcsan`` (or ``__no_kcsan_or_inline`` for

  ``__always_inline`` functions). To dynamically control for which functions

  data races are reported, see the `debugfs`_ blacklist/whitelist feature.





To disable KCSAN on a per-file basis, add to the ``Makefile``::

* To disable data race detection for a particular compilation unit, add to the

  ``Makefile``::





    KCSAN_SANITIZE_file.o := n

    KCSAN_SANITIZE_file.o := n





KCSAN also understands the ``data_race(expr)`` annotation, which tells KCSAN

* To disable data race detection for all compilation units listed in a

that any data races due to accesses in ``expr`` should be ignored and resulting

  ``Makefile``, add to the respective ``Makefile``::

behaviour when encountering a data race is deemed safe.



    KCSAN_SANITIZE := n





debugfs

debugfs

~~~~~~~

~~~~~~~

include/asm-generic/atomic-instrumented.h

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include/asm-generic/atomic-long.h

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include/linux/atomic-fallback.h

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include/linux/compiler-gcc.h

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#endif

#endif





#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)

#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)

#define __no_sanitize_thread                                                   \

#define __no_sanitize_thread __attribute__((no_sanitize_thread))

	__attribute__((__noinline__)) __attribute__((no_sanitize_thread))

#else

#else

#define __no_sanitize_thread

#define __no_sanitize_thread

#endif

#endif