From: Nick Desaulniers <ndesaulniers@google.com>
To: miguel.ojeda.sandonis@gmail.com
Cc: sedat.dilek@gmail.com, will@kernel.org, jpoimboe@redhat.com,
naveen.n.rao@linux.vnet.ibm.com, davem@davemloft.net,
paul.burton@mips.com, clang-built-linux@googlegroups.com,
linux-kernel@vger.kernel.org,
Nick Desaulniers <ndesaulniers@google.com>
Subject: [PATCH v3 06/14] arm: prefer __section from compiler_attributes.h
Date: Wed, 28 Aug 2019 15:55:27 -0700 [thread overview]
Message-ID: <20190828225535.49592-7-ndesaulniers@google.com> (raw)
In-Reply-To: <20190828225535.49592-1-ndesaulniers@google.com>
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
Link: https://github.com/ClangBuiltLinux/linux/issues/619
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
---
arch/arm/include/asm/cache.h | 2 +-
arch/arm/include/asm/mach/arch.h | 4 ++--
arch/arm/include/asm/setup.h | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm/include/asm/cache.h b/arch/arm/include/asm/cache.h
index 1d65ed3a2755..cc06079600e0 100644
--- a/arch/arm/include/asm/cache.h
+++ b/arch/arm/include/asm/cache.h
@@ -24,6 +24,6 @@
#define ARCH_SLAB_MINALIGN 8
#endif
-#define __read_mostly __attribute__((__section__(".data..read_mostly")))
+#define __read_mostly __section(.data..read_mostly)
#endif
diff --git a/arch/arm/include/asm/mach/arch.h b/arch/arm/include/asm/mach/arch.h
index e7df5a822cab..2986f6b4862d 100644
--- a/arch/arm/include/asm/mach/arch.h
+++ b/arch/arm/include/asm/mach/arch.h
@@ -81,7 +81,7 @@ extern const struct machine_desc __arch_info_begin[], __arch_info_end[];
#define MACHINE_START(_type,_name) \
static const struct machine_desc __mach_desc_##_type \
__used \
- __attribute__((__section__(".arch.info.init"))) = { \
+ __section(.arch.info.init) = { \
.nr = MACH_TYPE_##_type, \
.name = _name,
@@ -91,7 +91,7 @@ static const struct machine_desc __mach_desc_##_type \
#define DT_MACHINE_START(_name, _namestr) \
static const struct machine_desc __mach_desc_##_name \
__used \
- __attribute__((__section__(".arch.info.init"))) = { \
+ __section(.arch.info.init) = { \
.nr = ~0, \
.name = _namestr,
diff --git a/arch/arm/include/asm/setup.h b/arch/arm/include/asm/setup.h
index 67d20712cb48..00190f1f0574 100644
--- a/arch/arm/include/asm/setup.h
+++ b/arch/arm/include/asm/setup.h
@@ -14,7 +14,7 @@
#include <uapi/asm/setup.h>
-#define __tag __used __attribute__((__section__(".taglist.init")))
+#define __tag __used __section(.taglist.init)
#define __tagtable(tag, fn) \
static const struct tagtable __tagtable_##fn __tag = { tag, fn }
--
2.23.0.187.g17f5b7556c-goog
next prev parent reply other threads:[~2019-08-28 22:56 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-28 22:55 [PATCH v3 00/14] treewide: prefer __section from compiler_attributes.h Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 01/14] s390/boot: fix section name escaping Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 02/14] include/linux/compiler.h: prefer __section from compiler_attributes.h Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 03/14] parisc: " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 04/14] um: " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 05/14] ia64: " Nick Desaulniers
2019-08-28 22:55 ` Nick Desaulniers [this message]
2019-08-28 22:55 ` [PATCH v3 07/14] mips: " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 08/14] sparc: " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 09/14] powerpc: prefer __section and __printf " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 10/14] x86: prefer __section " Nick Desaulniers
2019-08-29 14:14 ` Miguel Ojeda
2019-08-29 14:22 ` Miguel Ojeda
2019-08-28 22:55 ` [PATCH v3 11/14] include/asm-generic: " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 12/14] include/linux: " Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 13/14] include/linux/compiler.h: remove unused KENTRY macro Nick Desaulniers
2019-08-28 22:55 ` [PATCH v3 14/14] compiler_attributes.h: add note about __section Nick Desaulniers
2019-08-29 20:24 ` [PATCH v3 00/14] treewide: prefer __section from compiler_attributes.h Miguel Ojeda
2019-08-29 20:37 ` Sedat Dilek
2019-08-29 20:47 ` Nick Desaulniers
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