Commit 61d56d7a authored Jun 18, 2020 by Marco Elver Committed by Paul E. McKenney Jun 29, 2020

kcsan: Disable branch tracing in core runtime

Disable branch tracing in core KCSAN runtime if branches are being
traced (TRACE_BRANCH_PROFILING). This it to avoid its performance
impact, but also avoid recursion in case KCSAN is enabled for the branch
tracing runtime.

The latter had already been a problem for KASAN:
https://lore.kernel.org/lkml/CANpmjNOeXmD5E3O50Z3MjkiuCYaYOPyi+1rq=GZvEKwBvLR0Ug@mail.gmail.com/



Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

parent 2839a232

kernel/kcsan/Makefile

+1 −1

Original line number	Diff line number	Diff line
		@@ -8,7 +8,7 @@ CFLAGS_REMOVE_debugfs.o = $(CC_FLAGS_FTRACE)
		CFLAGS_REMOVE_report.o = $(CC_FLAGS_FTRACE)

		CFLAGS_core.o := $(call cc-option,-fno-conserve-stack) \
		-fno-stack-protector
		-fno-stack-protector -DDISABLE_BRANCH_PROFILING

		obj-y := core.o debugfs.o report.o
		obj-$(CONFIG_KCSAN_SELFTEST) += selftest.o

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