Re: [PATCH] treewide: Remove stringification from __alias macro definition

2020-10-30 Thread Miguel Ojeda 
On Fri, Oct 30, 2020 at 4:07 AM Joe Perches  wrote:
>
> Like the old __section macro, the __alias macro uses macro # stringification
> to create quotes around the symbol name used in the __attribute__.

Hmm... isn't this V2? It seems none of the Acks/Reviews were picked
up, did something major change?

Cheers,
Miguel

Re: [PATCH] treewide: Remove stringification from __alias macro definition

2020-10-30 Thread Nathan Chancellor 
On Thu, Oct 29, 2020 at 08:07:31PM -0700, Joe Perches wrote:
> Like the old __section macro, the __alias macro uses macro # stringification
> to create quotes around the symbol name used in the __attribute__.
> 
> This can cause differences between gcc and clang when the stringification
> itself contains a quote character.  So avoid these differences by always
> using quotes to define the aliased symbol.
> 
> Remove the stringification and add quotes and when necessary a stringification
> when existing uses have a ## concatenation.
> 
> Signed-off-by: Joe Perches 

Reviewed-by: Nathan Chancellor 

> ---
> 
> Unlike the __section macro conversion in commit 33def8498fdd
> ("treewide: Convert macro and uses of __section(foo) to __section("foo")")
> this one was done by hand.
> 
> No other use of __alias exists in the kernel.
> 
> This patch does _not_ convert any uses of __attribute__((alias("")))
> so it should not cause any compilation issues.
> 
>  arch/x86/boot/compressed/string.c   |  6 +++---
>  arch/x86/include/asm/syscall_wrapper.h  |  2 +-
>  drivers/firmware/efi/runtime-wrappers.c |  2 +-
>  include/linux/compiler_attributes.h |  2 +-
>  kernel/kcsan/core.c | 10 +-
>  lib/crc32.c |  4 ++--
>  lib/crypto/aes.c|  4 ++--
>  mm/kasan/generic.c  |  8 
>  8 files changed, 19 insertions(+), 19 deletions(-)
> 
> diff --git a/arch/x86/boot/compressed/string.c 
> b/arch/x86/boot/compressed/string.c
> index 81fc1eaa3229..d38b122f51ef 100644
> --- a/arch/x86/boot/compressed/string.c
> +++ b/arch/x86/boot/compressed/string.c
> @@ -75,7 +75,7 @@ void *memcpy(void *dest, const void *src, size_t n)
>  }
>  
>  #ifdef CONFIG_KASAN
> -extern void *__memset(void *s, int c, size_t n) __alias(memset);
> -extern void *__memmove(void *dest, const void *src, size_t n) 
> __alias(memmove);
> -extern void *__memcpy(void *dest, const void *src, size_t n) __alias(memcpy);
> +extern void *__memset(void *s, int c, size_t n) __alias("memset");
> +extern void *__memmove(void *dest, const void *src, size_t n) 
> __alias("memmove");
> +extern void *__memcpy(void *dest, const void *src, size_t n) 
> __alias("memcpy");
>  #endif
> diff --git a/arch/x86/include/asm/syscall_wrapper.h 
> b/arch/x86/include/asm/syscall_wrapper.h
> index a84333adeef2..f19d1bbbff3d 100644
> --- a/arch/x86/include/asm/syscall_wrapper.h
> +++ b/arch/x86/include/asm/syscall_wrapper.h
> @@ -69,7 +69,7 @@ extern long __ia32_sys_ni_syscall(const struct pt_regs 
> *regs);
>   long __##abi##_##name(const struct pt_regs *regs);  \
>   ALLOW_ERROR_INJECTION(__##abi##_##name, ERRNO); \
>   long __##abi##_##name(const struct pt_regs *regs)   \
> - __alias(__do_##name);
> + __alias("__do_" #name);
>  
>  #define __SYS_STUBx(abi, name, ...)  \
>   long __##abi##_##name(const struct pt_regs *regs);  \
> diff --git a/drivers/firmware/efi/runtime-wrappers.c 
> b/drivers/firmware/efi/runtime-wrappers.c
> index 1410beaef5c3..14e380ac65d4 100644
> --- a/drivers/firmware/efi/runtime-wrappers.c
> +++ b/drivers/firmware/efi/runtime-wrappers.c
> @@ -162,7 +162,7 @@ static DEFINE_SEMAPHORE(efi_runtime_lock);
>   * Expose the EFI runtime lock to the UV platform
>   */
>  #ifdef CONFIG_X86_UV
> -extern struct semaphore __efi_uv_runtime_lock __alias(efi_runtime_lock);
> +extern struct semaphore __efi_uv_runtime_lock __alias("efi_runtime_lock");
>  #endif
>  
>  /*
> diff --git a/include/linux/compiler_attributes.h 
> b/include/linux/compiler_attributes.h
> index ea7b756b1c8f..4819512c9abd 100644
> --- a/include/linux/compiler_attributes.h
> +++ b/include/linux/compiler_attributes.h
> @@ -42,7 +42,7 @@
>  /*
>   *   gcc: 
> https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-alias-function-attribute
>   */
> -#define __alias(symbol) __attribute__((__alias__(#symbol)))
> +#define __alias(symbol) __attribute__((__alias__(symbol)))
>  
>  /*
>   *   gcc: 
> https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-aligned-function-attribute
> diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c
> index 3994a217bde7..465f6cfc317c 100644
> --- a/kernel/kcsan/core.c
> +++ b/kernel/kcsan/core.c
> @@ -814,7 +814,7 @@ EXPORT_SYMBOL(__kcsan_check_access);
>   }  \
>   EXPORT_SYMBOL(__tsan_read##size);  \
>   void __tsan_unaligned_read##size(void *ptr)\
> - __alias(__tsan_read##size);\
> + __alias("__tsan_read" #size);  \
>   EXPORT_SYMBOL(__tsan_unaligned_read##size);\
>   void __tsan_write##size(void *ptr);

[PATCH] treewide: Remove stringification from __alias macro definition

2020-10-29 Thread Joe Perches 
Like the old __section macro, the __alias macro uses macro # stringification
to create quotes around the symbol name used in the __attribute__.

This can cause differences between gcc and clang when the stringification
itself contains a quote character.  So avoid these differences by always
using quotes to define the aliased symbol.

Remove the stringification and add quotes and when necessary a stringification
when existing uses have a ## concatenation.

Signed-off-by: Joe Perches 
---

Unlike the __section macro conversion in commit 33def8498fdd
("treewide: Convert macro and uses of __section(foo) to __section("foo")")
this one was done by hand.

No other use of __alias exists in the kernel.

This patch does _not_ convert any uses of __attribute__((alias("")))
so it should not cause any compilation issues.

 arch/x86/boot/compressed/string.c   |  6 +++---
 arch/x86/include/asm/syscall_wrapper.h  |  2 +-
 drivers/firmware/efi/runtime-wrappers.c |  2 +-
 include/linux/compiler_attributes.h |  2 +-
 kernel/kcsan/core.c | 10 +-
 lib/crc32.c |  4 ++--
 lib/crypto/aes.c|  4 ++--
 mm/kasan/generic.c  |  8 
 8 files changed, 19 insertions(+), 19 deletions(-)

diff --git a/arch/x86/boot/compressed/string.c 
b/arch/x86/boot/compressed/string.c
index 81fc1eaa3229..d38b122f51ef 100644
--- a/arch/x86/boot/compressed/string.c
+++ b/arch/x86/boot/compressed/string.c
@@ -75,7 +75,7 @@ void *memcpy(void *dest, const void *src, size_t n)
 }
 
 #ifdef CONFIG_KASAN
-extern void *__memset(void *s, int c, size_t n) __alias(memset);
-extern void *__memmove(void *dest, const void *src, size_t n) __alias(memmove);
-extern void *__memcpy(void *dest, const void *src, size_t n) __alias(memcpy);
+extern void *__memset(void *s, int c, size_t n) __alias("memset");
+extern void *__memmove(void *dest, const void *src, size_t n) 
__alias("memmove");
+extern void *__memcpy(void *dest, const void *src, size_t n) __alias("memcpy");
 #endif
diff --git a/arch/x86/include/asm/syscall_wrapper.h 
b/arch/x86/include/asm/syscall_wrapper.h
index a84333adeef2..f19d1bbbff3d 100644
--- a/arch/x86/include/asm/syscall_wrapper.h
+++ b/arch/x86/include/asm/syscall_wrapper.h
@@ -69,7 +69,7 @@ extern long __ia32_sys_ni_syscall(const struct pt_regs *regs);
long __##abi##_##name(const struct pt_regs *regs);  \
ALLOW_ERROR_INJECTION(__##abi##_##name, ERRNO); \
long __##abi##_##name(const struct pt_regs *regs)   \
-   __alias(__do_##name);
+   __alias("__do_" #name);
 
 #define __SYS_STUBx(abi, name, ...)\
long __##abi##_##name(const struct pt_regs *regs);  \
diff --git a/drivers/firmware/efi/runtime-wrappers.c 
b/drivers/firmware/efi/runtime-wrappers.c
index 1410beaef5c3..14e380ac65d4 100644
--- a/drivers/firmware/efi/runtime-wrappers.c
+++ b/drivers/firmware/efi/runtime-wrappers.c
@@ -162,7 +162,7 @@ static DEFINE_SEMAPHORE(efi_runtime_lock);
  * Expose the EFI runtime lock to the UV platform
  */
 #ifdef CONFIG_X86_UV
-extern struct semaphore __efi_uv_runtime_lock __alias(efi_runtime_lock);
+extern struct semaphore __efi_uv_runtime_lock __alias("efi_runtime_lock");
 #endif
 
 /*
diff --git a/include/linux/compiler_attributes.h 
b/include/linux/compiler_attributes.h
index ea7b756b1c8f..4819512c9abd 100644
--- a/include/linux/compiler_attributes.h
+++ b/include/linux/compiler_attributes.h
@@ -42,7 +42,7 @@
 /*
  *   gcc: 
https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-alias-function-attribute
  */
-#define __alias(symbol) __attribute__((__alias__(#symbol)))
+#define __alias(symbol) __attribute__((__alias__(symbol)))
 
 /*
  *   gcc: 
https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-aligned-function-attribute
diff --git a/kernel/kcsan/core.c b/kernel/kcsan/core.c
index 3994a217bde7..465f6cfc317c 100644
--- a/kernel/kcsan/core.c
+++ b/kernel/kcsan/core.c
@@ -814,7 +814,7 @@ EXPORT_SYMBOL(__kcsan_check_access);
}  \
EXPORT_SYMBOL(__tsan_read##size);  \
void __tsan_unaligned_read##size(void *ptr)\
-   __alias(__tsan_read##size);\
+   __alias("__tsan_read" #size);  \
EXPORT_SYMBOL(__tsan_unaligned_read##size);\
void __tsan_write##size(void *ptr);\
void __tsan_write##size(void *ptr) \
@@ -823,7 +823,7 @@ EXPORT_SYMBOL(__kcsan_check_access);
}  \
EXPORT_SYMBOL(__tsan_write##size);