Commit Graph

7 Commits

Author SHA1 Message Date
Marco Elver
e68dcd8eac kcsan: Re-add GCC as a supported compiler
GCC version 11 recently implemented all requirements to correctly
support KCSAN:

1. Correct no_sanitize-attribute inlining behaviour:
   https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=4089df8ef4a63126b0774c39b6638845244c20d2

2. --param=tsan-distinguish-volatile
   https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=ab2789ec507a94f1a75a6534bca51c7b39037ce0

3. --param=tsan-instrument-func-entry-exit
   https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=06712fc68dc9843d9af7c7ac10047f49d305ad76

Therefore, we can re-enable GCC for KCSAN, and document the new compiler
requirements.

Signed-off-by: Marco Elver <elver@google.com>
Cc: Martin Liska <mliska@suse.cz>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-06-29 12:04:48 -07:00
Peter Zijlstra
e79302ae8c kcsan: Remove __no_kcsan_or_inline
There are no more user of this function attribute, also, with us now
actively supporting '__no_kcsan inline' it doesn't make sense to have
in any case.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2020-06-15 14:10:08 +02:00
Marco Elver
0bb9ab3a6f kcsan: Update Documentation to change supported compilers
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
2020-06-11 20:04:02 +02:00
Marco Elver
d8949ef1d9 kcsan: Introduce scoped ASSERT_EXCLUSIVE macros
Introduce ASSERT_EXCLUSIVE_*_SCOPED(), which provide an intuitive
interface to use the scoped-access feature, without having to explicitly
mark the start and end of the desired scope. Basing duration of the
checks on scope avoids accidental misuse and resulting false positives,
which may be hard to debug. See added comments for usage.

The macros are implemented using __attribute__((__cleanup__(func))),
which is supported by all compilers that currently support KCSAN.

Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-04-13 17:18:13 -07:00
Marco Elver
e7325b774c kcsan: Update Documentation/dev-tools/kcsan.rst
Extend and improve based on recent changes, and summarize important
bits that have been missing. Tested with "make htmldocs".

Signed-off-by: Marco Elver <elver@google.com>
Cc: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-03-25 09:56:00 -07:00
Marco Elver
7161177481 kcsan: Document static blacklisting options
Updates the section on "Selective analysis", listing all available
options to blacklist reporting data races for: specific accesses,
functions, compilation units, and entire directories.

These options should provide adequate control for maintainers to opt out
of KCSAN analysis at varying levels of granularity. It is hoped to
provide the required control to reflect preferences for handling data
races across the kernel.

Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-01-07 07:47:23 -08:00
Marco Elver
905e672b3a kcsan: Add Documentation entry in dev-tools
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2019-11-16 07:23:13 -08:00