Re: [PATCH v3 07/12] klp-build: Add LoongArch syscall patching macro

[Joe Lawrence <joe.lawrence@redhat.com>]

On Tue, Jul 07, 2026 at 03:20:26PM +0800, George Guo wrote:
> From: George Guo <guodongtai@kylinos.cn>
> 
> Add LoongArch support for KLP_SYSCALL_DEFINEx(), mirroring the generic
> __SYSCALL_DEFINEx() pattern from include/linux/syscalls.h.
> 
> Co-developed-by: Kexin Liu <liukexin@kylinos.cn>
> Signed-off-by: Kexin Liu <liukexin@kylinos.cn>
> Signed-off-by: George Guo <guodongtai@kylinos.cn>
> ---
>  include/linux/livepatch_helpers.h | 22 ++++++++++++++++++++++
>  1 file changed, 22 insertions(+)
> 
> diff --git a/include/linux/livepatch_helpers.h b/include/linux/livepatch_helpers.h
> index 4b647b83865f..a8aad067177b 100644
> --- a/include/linux/livepatch_helpers.h
> +++ b/include/linux/livepatch_helpers.h
> @@ -91,6 +91,28 @@
>  	}								\
>  	static inline long __klp_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
>  
> +#elif defined(CONFIG_LOONGARCH)
> +
> +#define __KLP_SYSCALL_DEFINEx(x, name, ...)                             \
> +	__diag_push();                                                  \
> +	__diag_ignore(GCC, 8, "-Wattribute-alias",                      \
> +		      "Type aliasing is used to sanitize syscall arguments");\
> +	asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))       \
> +		__attribute__((alias(__stringify(__se_sys##name))));    \
> +	ALLOW_ERROR_INJECTION(sys##name, ERRNO);                        \
> +	static inline long __klp_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
> +	asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
> +	asmlinkage long __attribute__((optimize("-fno-optimize-sibling-calls")))\
> +			__se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__))  \
> +	{                                                               \
> +		long ret = __klp_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
> +		__MAP(x,__SC_TEST,__VA_ARGS__);                         \
> +		__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__));       \
> +		return ret;                                             \
> +	}                                                               \
> +	__diag_pop();                                                   \
> +	static inline long __klp_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
> +
>  #endif

Nit: The other macros in livepatch_helpers use tabs to pad out to the
line continuation '\'.

--
Joe