diff mbox series

[4/8] kbuild: avoid static_assert for genksyms

Message ID 20201211213638.89W7IFB2b%akpm@linux-foundation.org
State New
Headers show
Series None | expand

Commit Message

Andrew Morton Dec. 11, 2020, 9:36 p.m. UTC 
From: Arnd Bergmann <arnd@arndb.de>

Subject: kbuild: avoid static_assert for genksyms

genksyms does not know or care about the _Static_assert() built-in,
and sometimes falls back to ignoring the later symbols, which causes
undefined behavior such as

WARNING: modpost: EXPORT symbol "ethtool_set_ethtool_phy_ops" [vmlinux] version generation failed, symbol will not be versioned.
ld: net/ethtool/common.o: relocation R_AARCH64_ABS32 against `__crc_ethtool_set_ethtool_phy_ops' can not be used when making a shared object
net/ethtool/common.o:(_ftrace_annotated_branch+0x0): dangerous relocation: unsupported relocation

Redefine static_assert for genksyms to avoid that.

Link: https://lkml.kernel.org/r/20201203230955.1482058-1-arnd@kernel.org
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Michal Marek <michal.lkml@markovi.net>
Cc: Kees Cook <keescook@chromium.org>
Cc: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Cc: Marco Elver <elver@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

---

 include/linux/build_bug.h |    5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

--- a/include/linux/build_bug.h~kbuild-avoid-static_assert-for-genksyms
+++ a/include/linux/build_bug.h
@@ -77,4 +77,9 @@ 
 #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr)
 #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
 
+#ifdef __GENKSYMS__
+/* genksyms gets confused by _Static_assert */
+#define _Static_assert(expr, ...)
+#endif
+
 #endif	/* _LINUX_BUILD_BUG_H */