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Date:   Tue, 29 Sep 2020 12:25:49 -0700
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Subject: [PATCH v2] srcu: avoid escaped section names
From:   Nick Desaulniers <ndesaulniers@google.com>
To:     "Paul E . McKenney" <paulmck@kernel.org>
Cc:     Steven Rostedt <rostedt@goodmis.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Lai Jiangshan <jiangshanlai@gmail.com>,
        Josh Triplett <josh@joshtriplett.org>,
        Kees Cook <keescook@chromium.org>,
        linux-kernel@vger.kernel.org, rcu@vger.kernel.org,
        clang-built-linux@googlegroups.com,
        Nick Desaulniers <ndesaulniers@google.com>
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The stringification operator, `#`, in the preprocessor escapes strings.
For example, `# "foo"` becomes `"\"foo\""`.  GCC and Clang differ in how
they treat section names that contain \".

The portable solution is to not use a string literal with the
preprocessor stringification operator.

Link: https://bugs.llvm.org/show_bug.cgi?id=42950
Fixes: commit fe15b50cdeee ("srcu: Allocate per-CPU data for DEFINE_SRCU() in modules")
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
Changes V1->V2:
* drop unrelated Kconfig changes accidentally committed in v1.

 include/linux/srcutree.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/srcutree.h b/include/linux/srcutree.h
index 9cfcc8a756ae..9de652f4e1bd 100644
--- a/include/linux/srcutree.h
+++ b/include/linux/srcutree.h
@@ -124,7 +124,7 @@ struct srcu_struct {
 # define __DEFINE_SRCU(name, is_static)					\
 	is_static struct srcu_struct name;				\
 	struct srcu_struct * const __srcu_struct_##name			\
-		__section("___srcu_struct_ptrs") = &name
+		__section(___srcu_struct_ptrs) = &name
 #else
 # define __DEFINE_SRCU(name, is_static)					\
 	static DEFINE_PER_CPU(struct srcu_data, name##_srcu_data);	\
-- 
2.28.0.709.gb0816b6eb0-goog