Re: [RFC PATCH -next V3 1/6] x86: fix function define in copy_mc_to_user

From: Kefeng Wang
Date: Tue Apr 12 2022 - 08:31:01 EST



On 2022/4/12 15:25, Tong Tiangen wrote:
X86 has it's implementation of copy_mc_to_user but not use #define to
declare.

This may cause problems, for example, if other architectures open
CONFIG_ARCH_HAS_COPY_MC, but want to use copy_mc_to_user() outside the
architecture, the code add to include/linux/uaddess.h is as follows:

#ifndef copy_mc_to_user
static inline unsigned long __must_check
copy_mc_to_user(void *dst, const void *src, size_t cnt)
{
...
}
#endif

Then this definition will conflict with the implementation of X86 and cause
compilation errors.
Does powerpc need this define?

Fixes: ec6347bb4339 ("x86, powerpc: Rename memcpy_mcsafe() to copy_mc_to_{user, kernel}()")
Signed-off-by: Tong Tiangen <tongtiangen@xxxxxxxxxx>
---
arch/x86/include/asm/uaccess.h | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index f78e2b3501a1..e18c5f098025 100644
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -415,6 +415,7 @@ copy_mc_to_kernel(void *to, const void *from, unsigned len);
unsigned long __must_check
copy_mc_to_user(void *to, const void *from, unsigned len);
+#define copy_mc_to_user copy_mc_to_user
#endif
/*