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McKenney" Cc: LKMM Maintainers -- Akira Yokosawa , Alan Stern , Alexander Potapenko , Andrea Parri , Andrey Konovalov , Andy Lutomirski , Ard Biesheuvel , Arnd Bergmann , Boqun Feng , Borislav Petkov , Daniel Axtens , Daniel Lustig , Dave Hansen , David Howells , Dmitry Vyukov , "H. Peter Anvin" , Ingo Molnar , Jade Alglave , Joel Fernandes , Jonathan Corbet , Josh Poimboeuf , Luc Maranget , Mark Rutland , Nicholas Piggin , Peter Zijlstra , Thomas Gleixner , Will Deacon , kasan-dev , linux-arch , "open list:DOCUMENTATION" , linux-efi@vger.kernel.org, Linux Kbuild mailing list , LKML , Linux Memory Management List , "the arch/x86 maintainers" Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 5 Nov 2019 at 15:20, Paul E. McKenney wrote: > > On Tue, Nov 05, 2019 at 12:10:56PM +0100, Marco Elver wrote: > > On Mon, 4 Nov 2019 at 20:47, Paul E. McKenney wrote: > > > > > > On Mon, Nov 04, 2019 at 07:41:30PM +0100, Marco Elver wrote: > > > > On Mon, 4 Nov 2019 at 17:47, Paul E. McKenney wrote: > > > > > > > > > > On Mon, Nov 04, 2019 at 03:27:36PM +0100, Marco Elver 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@mail.gmail.com > > > > > > > > > > > > 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 > > > > > > > > > > Making this more accessible to more people seems like a good thing. > > > > > So, for the series: > > > > > > > > > > Acked-by: Paul E. McKenney > > > > > > > > Much appreciated. Thanks, Paul! > > > > > > > > Any suggestions which tree this could eventually land in? > > > > > > I would guess that Dmitry might have some suggestions. > > > > I checked and we're both unclear what the most obvious tree to land in > > is (the other sanitizers are mm related, which KCSAN is not). > > > > One suggestion that comes to my mind is for KCSAN to go through the > > same tree (rcu?) as the LKMM due to their inherent relationship. Would > > that make most sense? > > It works for me, though you guys have to continue to be the main > developers. ;-) Great, thanks. We did add an entry to MAINTAINERS, so yes of course. :-) > I will go through the patches more carefully, and please look into the > kbuild test robot complaint. I just responded to that, it seems to be a sparse problem. Thanks, -- Marco > Thanx, Paul > > > Thanks, > > -- Marco > > > > > > > > > > > > Changelog > > > > > > --------- > > > > > > v3: > > > > > > * Major changes: > > > > > > - Add microbenchmark. > > > > > > - Add instruction watchpoint skip randomization. > > > > > > - Refactor API and core runtime fast-path and slow-path. Compared to > > > > > > the previous version, with a default config and benchmarked using the > > > > > > added microbenchmark, this version is 3.8x faster. > > > > > > - Make __tsan_unaligned __alias of generic accesses. > > > > > > - Rename kcsan_{begin,end}_atomic -> > > > > > > kcsan_{nestable,flat}_atomic_{begin,end} > > > > > > - For filter list in debugfs.c use kmalloc+krealloc instead of > > > > > > kvmalloc. > > > > > > - Split Documentation into separate patch. > > > > > > > > > > > > v2: http://lkml.kernel.org/r/20191017141305.146193-1-elver@google.com > > > > > > * Major changes: > > > > > > - Replace kcsan_check_access(.., {true, false}) with > > > > > > kcsan_check_{read,write}. > > > > > > - Change atomic-instrumented.h to use __atomic_check_{read,write}. > > > > > > - Use common struct kcsan_ctx in task_struct and for per-CPU interrupt > > > > > > contexts. > > > > > > > > > > > > v1: http://lkml.kernel.org/r/20191016083959.186860-1-elver@google.com > > > > > > > > > > > > Marco Elver (9): > > > > > > kcsan: Add Kernel Concurrency Sanitizer infrastructure > > > > > > kcsan: Add Documentation entry in dev-tools > > > > > > 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/index.rst | 1 + > > > > > > Documentation/dev-tools/kcsan.rst | 217 +++++++++ > > > > > > MAINTAINERS | 11 + > > > > > > Makefile | 3 +- > > > > > > arch/x86/Kconfig | 1 + > > > > > > arch/x86/boot/Makefile | 2 + > > > > > > arch/x86/boot/compressed/Makefile | 2 + > > > > > > arch/x86/entry/vdso/Makefile | 3 + > > > > > > arch/x86/include/asm/bitops.h | 6 +- > > > > > > arch/x86/kernel/Makefile | 7 + > > > > > > arch/x86/kernel/cpu/Makefile | 3 + > > > > > > arch/x86/lib/Makefile | 4 + > > > > > > arch/x86/mm/Makefile | 3 + > > > > > > arch/x86/purgatory/Makefile | 2 + > > > > > > arch/x86/realmode/Makefile | 3 + > > > > > > arch/x86/realmode/rm/Makefile | 3 + > > > > > > drivers/firmware/efi/libstub/Makefile | 2 + > > > > > > include/asm-generic/atomic-instrumented.h | 393 +++++++-------- > > > > > > 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 | 97 ++++ > > > > > > include/linux/kcsan.h | 115 +++++ > > > > > > include/linux/sched.h | 4 + > > > > > > include/linux/seqlock.h | 51 +- > > > > > > init/init_task.c | 8 + > > > > > > init/main.c | 2 + > > > > > > kernel/Makefile | 6 + > > > > > > kernel/kcsan/Makefile | 11 + > > > > > > kernel/kcsan/atomic.h | 27 ++ > > > > > > kernel/kcsan/core.c | 560 ++++++++++++++++++++++ > > > > > > kernel/kcsan/debugfs.c | 275 +++++++++++ > > > > > > kernel/kcsan/encoding.h | 94 ++++ > > > > > > kernel/kcsan/kcsan.h | 131 +++++ > > > > > > kernel/kcsan/report.c | 306 ++++++++++++ > > > > > > kernel/kcsan/test.c | 121 +++++ > > > > > > kernel/sched/Makefile | 6 + > > > > > > lib/Kconfig.debug | 2 + > > > > > > lib/Kconfig.kcsan | 119 +++++ > > > > > > lib/Makefile | 3 + > > > > > > mm/Makefile | 8 + > > > > > > scripts/Makefile.kcsan | 6 + > > > > > > scripts/Makefile.lib | 10 + > > > > > > scripts/atomic/gen-atomic-instrumented.sh | 17 +- > > > > > > tools/objtool/check.c | 18 + > > > > > > 46 files changed, 2526 insertions(+), 206 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.h > > > > > > 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.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 > > > > > > > > > > > > -- > > > > > > 2.24.0.rc1.363.gb1bccd3e3d-goog > > > > > > > > > > > > > > > > -- > > > > > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > > > > > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > > > > > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20191104164717.GE20975%40paulmck-ThinkPad-P72. > > > > > > -- > > > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > > > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > > > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20191104194658.GK20975%40paulmck-ThinkPad-P72. > > -- > You received this message because you are subscribed to the Google Groups "kasan-dev" group. > To unsubscribe from this group and stop receiving emails from it, send an email to kasan-dev+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/kasan-dev/20191105142035.GR20975%40paulmck-ThinkPad-P72.