Re: [PATCH 0/8] Add Kernel Concurrency Sanitizer (KCSAN)

[Marco Elver]

On Wed, 16 Oct 2019 at 10:41, Marco Elver <elver@xxxxxxxxxx> wrote:
>
> This is the patch-series for the Kernel Concurrency Sanitizer (KCSAN).
> KCSAN is a sampling watchpoint-based data-race detector. More details
> are included in Documentation/dev-tools/kcsan.rst. This patch-series
> only enables KCSAN for x86, but we expect adding support for other
> architectures is relatively straightforward (we are aware of
> experimental ARM64 and POWER support).
>
> To gather early feedback, we announced KCSAN back in September, and
> have integrated the feedback where possible:
> http://lkml.kernel.org/r/CANpmjNPJ_bHjfLZCAPV23AXFfiPiyXXqqu72n6TgWzb2Gnu1eA@xxxxxxxxxxxxxx
>
> We want to point out and acknowledge the work surrounding the LKMM,
> including several articles that motivate why data-races are dangerous
> [1, 2], justifying a data-race detector such as KCSAN.
> [1] https://lwn.net/Articles/793253/
> [2] https://lwn.net/Articles/799218/
>
> The current list of known upstream fixes for data-races found by KCSAN
> can be found here:
> https://github.com/google/ktsan/wiki/KCSAN#upstream-fixes-of-data-races-found-by-kcsan

Sent v2: http://lkml.kernel.org/r/20191017141305.146193-1-elver@xxxxxxxxxx

Many thanks,
-- Marco

> Marco Elver (8):
>   kcsan: Add Kernel Concurrency Sanitizer infrastructure
>   objtool, kcsan: Add KCSAN runtime functions to whitelist
>   build, kcsan: Add KCSAN build exceptions
>   seqlock, kcsan: Add annotations for KCSAN
>   seqlock: Require WRITE_ONCE surrounding raw_seqcount_barrier
>   asm-generic, kcsan: Add KCSAN instrumentation for bitops
>   locking/atomics, kcsan: Add KCSAN instrumentation
>   x86, kcsan: Enable KCSAN for x86
>
>  Documentation/dev-tools/kcsan.rst         | 202 ++++++++++
>  MAINTAINERS                               |  11 +
>  Makefile                                  |   3 +-
>  arch/x86/Kconfig                          |   1 +
>  arch/x86/boot/Makefile                    |   1 +
>  arch/x86/boot/compressed/Makefile         |   1 +
>  arch/x86/entry/vdso/Makefile              |   1 +
>  arch/x86/include/asm/bitops.h             |   2 +-
>  arch/x86/kernel/Makefile                  |   6 +
>  arch/x86/kernel/cpu/Makefile              |   3 +
>  arch/x86/lib/Makefile                     |   2 +
>  arch/x86/mm/Makefile                      |   3 +
>  arch/x86/purgatory/Makefile               |   1 +
>  arch/x86/realmode/Makefile                |   1 +
>  arch/x86/realmode/rm/Makefile             |   1 +
>  drivers/firmware/efi/libstub/Makefile     |   1 +
>  include/asm-generic/atomic-instrumented.h | 192 ++++++++-
>  include/asm-generic/bitops-instrumented.h |  18 +
>  include/linux/compiler-clang.h            |   9 +
>  include/linux/compiler-gcc.h              |   7 +
>  include/linux/compiler.h                  |  35 +-
>  include/linux/kcsan-checks.h              | 116 ++++++
>  include/linux/kcsan.h                     |  85 ++++
>  include/linux/sched.h                     |   7 +
>  include/linux/seqlock.h                   |  51 ++-
>  init/init_task.c                          |   6 +
>  init/main.c                               |   2 +
>  kernel/Makefile                           |   6 +
>  kernel/kcsan/Makefile                     |  14 +
>  kernel/kcsan/atomic.c                     |  21 +
>  kernel/kcsan/core.c                       | 458 ++++++++++++++++++++++
>  kernel/kcsan/debugfs.c                    | 225 +++++++++++
>  kernel/kcsan/encoding.h                   |  94 +++++
>  kernel/kcsan/kcsan.c                      |  81 ++++
>  kernel/kcsan/kcsan.h                      | 140 +++++++
>  kernel/kcsan/report.c                     | 307 +++++++++++++++
>  kernel/kcsan/test.c                       | 117 ++++++
>  kernel/sched/Makefile                     |   6 +
>  lib/Kconfig.debug                         |   2 +
>  lib/Kconfig.kcsan                         |  88 +++++
>  lib/Makefile                              |   3 +
>  mm/Makefile                               |   8 +
>  scripts/Makefile.kcsan                    |   6 +
>  scripts/Makefile.lib                      |  10 +
>  scripts/atomic/gen-atomic-instrumented.sh |   9 +-
>  tools/objtool/check.c                     |  17 +
>  46 files changed, 2364 insertions(+), 16 deletions(-)
>  create mode 100644 Documentation/dev-tools/kcsan.rst
>  create mode 100644 include/linux/kcsan-checks.h
>  create mode 100644 include/linux/kcsan.h
>  create mode 100644 kernel/kcsan/Makefile
>  create mode 100644 kernel/kcsan/atomic.c
>  create mode 100644 kernel/kcsan/core.c
>  create mode 100644 kernel/kcsan/debugfs.c
>  create mode 100644 kernel/kcsan/encoding.h
>  create mode 100644 kernel/kcsan/kcsan.c
>  create mode 100644 kernel/kcsan/kcsan.h
>  create mode 100644 kernel/kcsan/report.c
>  create mode 100644 kernel/kcsan/test.c
>  create mode 100644 lib/Kconfig.kcsan
>  create mode 100644 scripts/Makefile.kcsan
>
> --
> 2.23.0.700.g56cf767bdb-goog
>