[PATCH 1/7] kcsan: Improve some Kconfig comments

From: Marco Elver
Date: Mon Jun 07 2021 - 08:58:12 EST


Improve comment for CC_HAS_TSAN_COMPOUND_READ_BEFORE_WRITE. Also shorten
the comment above the "strictness" configuration options.

Signed-off-by: Marco Elver <elver@xxxxxxxxxx>
---
lib/Kconfig.kcsan | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/lib/Kconfig.kcsan b/lib/Kconfig.kcsan
index 0440f373248e..6152fbd5cbb4 100644
--- a/lib/Kconfig.kcsan
+++ b/lib/Kconfig.kcsan
@@ -40,10 +40,14 @@ menuconfig KCSAN

if KCSAN

-# Compiler capabilities that should not fail the test if they are unavailable.
config CC_HAS_TSAN_COMPOUND_READ_BEFORE_WRITE
def_bool (CC_IS_CLANG && $(cc-option,-fsanitize=thread -mllvm -tsan-compound-read-before-write=1)) || \
(CC_IS_GCC && $(cc-option,-fsanitize=thread --param tsan-compound-read-before-write=1))
+ help
+ The compiler instruments plain compound read-write operations
+ differently (++, --, +=, -=, |=, &=, etc.), which allows KCSAN to
+ distinguish them from other plain accesses. This is currently
+ supported by Clang 12 or later.

config KCSAN_VERBOSE
bool "Show verbose reports with more information about system state"
@@ -169,13 +173,9 @@ config KCSAN_REPORT_ONCE_IN_MS
reporting to avoid flooding the console with reports. Setting this
to 0 disables rate limiting.

-# The main purpose of the below options is to control reported data races (e.g.
-# in fuzzer configs), and are not expected to be switched frequently by other
-# users. We could turn some of them into boot parameters, but given they should
-# not be switched normally, let's keep them here to simplify configuration.
-#
-# The defaults below are chosen to be very conservative, and may miss certain
-# bugs.
+# The main purpose of the below options is to control reported data races, and
+# are not expected to be switched frequently by non-testers or at runtime.
+# The defaults are chosen to be conservative, and can miss certain bugs.

config KCSAN_REPORT_RACE_UNKNOWN_ORIGIN
bool "Report races of unknown origin"
--
2.32.0.rc1.229.g3e70b5a671-goog