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Subject[PATCH v2 11/14] include/asm-generic: prefer __section from compiler_attributes.h
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GCC unescapes escaped string section names while Clang does not. Because
__section uses the `#` stringification operator for the section name, it
doesn't need to be escaped.

Instead, we should:
1. Prefer __section(.section_name_no_quotes).
2. Only use __attribute__((__section(".section"))) when creating the
section name via C preprocessor (see the definition of __define_initcall
in arch/um/include/shared/init.h).

This antipattern was found with:
$ grep -e __section\(\" -e __section__\(\" -r

See the discussions in:
Link: https://bugs.llvm.org/show_bug.cgi?id=42950
Link: https://marc.info/?l=linux-netdev&m=156412960619946&w=2
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
include/asm-generic/error-injection.h | 2 +-
include/asm-generic/kprobes.h | 5 ++---
2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/include/asm-generic/error-injection.h b/include/asm-generic/error-injection.h
index 95a159a4137f..a593a50b33e3 100644
--- a/include/asm-generic/error-injection.h
+++ b/include/asm-generic/error-injection.h
@@ -23,7 +23,7 @@ struct error_injection_entry {
*/
#define ALLOW_ERROR_INJECTION(fname, _etype) \
static struct error_injection_entry __used \
- __attribute__((__section__("_error_injection_whitelist"))) \
+ __section(_error_injection_whitelist) \
_eil_addr_##fname = { \
.addr = (unsigned long)fname, \
.etype = EI_ETYPE_##_etype, \
diff --git a/include/asm-generic/kprobes.h b/include/asm-generic/kprobes.h
index 4a982089c95c..20d69719270f 100644
--- a/include/asm-generic/kprobes.h
+++ b/include/asm-generic/kprobes.h
@@ -9,12 +9,11 @@
* by using this macro.
*/
# define __NOKPROBE_SYMBOL(fname) \
-static unsigned long __used \
- __attribute__((__section__("_kprobe_blacklist"))) \
+static unsigned long __used __section(_kprobe_blacklist) \
_kbl_addr_##fname = (unsigned long)fname;
# define NOKPROBE_SYMBOL(fname) __NOKPROBE_SYMBOL(fname)
/* Use this to forbid a kprobes attach on very low level functions */
-# define __kprobes __attribute__((__section__(".kprobes.text")))
+# define __kprobes __section(.kprobes.text)
# define nokprobe_inline __always_inline
#else
# define NOKPROBE_SYMBOL(fname)
--
2.23.0.187.g17f5b7556c-goog
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