[PATCH 07/10] x86: fix duplicate extern declarations

[PATCH 07/10] x86: fix duplicate extern declarations

[Safocl Stollmannovic]

Compiling a kernel module with a C++ compiler results in a duplicate
echo ‘extern’ specifier error.
This occurs because the code contains , and
expands to  when processed by a C++ compiler.
The  specifier must be removed.
https://bugzilla.kernel.org/show_bug.cgi?id=222257

Signed-off-by: Safocl Stollmannovic <safocl88@gmail.com>
---
 arch/x86/include/asm/efi.h       | 2 +-
 arch/x86/include/asm/gsseg.h     | 2 +-
 arch/x86/include/asm/preempt.h   | 8 ++++----
 arch/x86/include/asm/processor.h | 2 +-
 arch/x86/include/asm/suspend.h   | 2 +-
 arch/x86/um/sys_call_table_32.c  | 4 ++--
 arch/x86/um/sys_call_table_64.c  | 4 ++--
 7 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index be58b7f5c..f5cb179b8 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -94,7 +94,7 @@ static inline void efi_fpu_end(void)
 #else /* !CONFIG_X86_32 */
 #define EFI_X86_KERNEL_ALLOC_LIMIT		EFI_ALLOC_LIMIT
 
-extern asmlinkage u64 __efi_call(void *fp, ...);
+asmlinkage u64 __efi_call(void *fp, ...);
 
 extern bool efi_disable_ibt_for_runtime;
 
diff --git a/arch/x86/include/asm/gsseg.h b/arch/x86/include/asm/gsseg.h
index ab6a595ce..81ef16081 100644
--- a/arch/x86/include/asm/gsseg.h
+++ b/arch/x86/include/asm/gsseg.h
@@ -12,7 +12,7 @@
 
 #ifdef CONFIG_X86_64
 
-extern asmlinkage void asm_load_gs_index(u16 selector);
+asmlinkage void asm_load_gs_index(u16 selector);
 
 /* Replace with "lkgs %di" once binutils support LKGS instruction */
 #define LKGS_DI _ASM_BYTES(0xf2,0x0f,0x00,0xf7)
diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
index d16d9c2f7..135695ae3 100644
--- a/arch/x86/include/asm/preempt.h
+++ b/arch/x86/include/asm/preempt.h
@@ -134,11 +134,11 @@ static __always_inline bool should_resched(int preempt_offset)
 
 #ifdef CONFIG_PREEMPTION
 
-extern asmlinkage void preempt_schedule(void);
-extern asmlinkage void preempt_schedule_thunk(void);
+asmlinkage void preempt_schedule(void);
+asmlinkage void preempt_schedule_thunk(void);
 
-extern asmlinkage void preempt_schedule_notrace(void);
-extern asmlinkage void preempt_schedule_notrace_thunk(void);
+asmlinkage void preempt_schedule_notrace(void);
+asmlinkage void preempt_schedule_notrace_thunk(void);
 
 #define __preempt_schedule() \
 	asm volatile ("call preempt_schedule_thunk" : ASM_CALL_CONSTRAINT);
diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h
index 77488ff5e..68d7292af 100644
--- a/arch/x86/include/asm/processor.h
+++ b/arch/x86/include/asm/processor.h
@@ -455,7 +455,7 @@ static inline unsigned long cpu_kernelmode_gs_base(int cpu)
 #endif
 }
 
-extern asmlinkage void entry_SYSCALL32_ignore(void);
+asmlinkage void entry_SYSCALL32_ignore(void);
 
 /* Save actual FS/GS selectors and bases to current->thread */
 void current_save_fsgs(void);
diff --git a/arch/x86/include/asm/suspend.h b/arch/x86/include/asm/suspend.h
index a892494ca..e29c071b9 100644
--- a/arch/x86/include/asm/suspend.h
+++ b/arch/x86/include/asm/suspend.h
@@ -11,4 +11,4 @@ extern unsigned long temp_pgt __visible;
 extern unsigned long relocated_restore_code __visible;
 extern int relocate_restore_code(void);
 /* Defined in hibernate_asm_32/64.S */
-extern asmlinkage __visible int restore_image(void);
+asmlinkage __visible int restore_image(void);
diff --git a/arch/x86/um/sys_call_table_32.c b/arch/x86/um/sys_call_table_32.c
index 51655133e..f79c0138e 100644
--- a/arch/x86/um/sys_call_table_32.c
+++ b/arch/x86/um/sys_call_table_32.c
@@ -9,7 +9,7 @@
 #include <linux/cache.h>
 #include <asm/syscall.h>
 
-extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
+asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
 				      unsigned long, unsigned long,
 				      unsigned long, unsigned long);
 
@@ -28,7 +28,7 @@ extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
 #define __SYSCALL_WITH_COMPAT(nr, native, compat)	__SYSCALL(nr, native)
 #define __SYSCALL_NORETURN __SYSCALL
 
-#define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
+#define __SYSCALL(nr, sym) asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
 #include <asm/syscalls_32.h>
 #undef  __SYSCALL
 
diff --git a/arch/x86/um/sys_call_table_64.c b/arch/x86/um/sys_call_table_64.c
index 943d414f2..555e65e66 100644
--- a/arch/x86/um/sys_call_table_64.c
+++ b/arch/x86/um/sys_call_table_64.c
@@ -9,7 +9,7 @@
 #include <linux/cache.h>
 #include <asm/syscall.h>
 
-extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
+asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
 				      unsigned long, unsigned long,
 				      unsigned long, unsigned long);
 
@@ -24,7 +24,7 @@ extern asmlinkage long sys_ni_syscall(unsigned long, unsigned long,
 
 #define __SYSCALL_NORETURN __SYSCALL
 
-#define __SYSCALL(nr, sym) extern asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
+#define __SYSCALL(nr, sym) asmlinkage long sym(unsigned long, unsigned long, unsigned long, unsigned long, unsigned long, unsigned long);
 #include <asm/syscalls_64.h>
 #undef  __SYSCALL
 
-- 
2.56.1

Re: [PATCH 07/10] x86: fix duplicate extern declarations

[sashiko-bot]

Thank you for your contribution! Sashiko AI review found 1 potential
issue to consider:
- [Low] x86: commit message corrupted by shell expansion and inaccurate
  for .c files
--

commit ef771365acc78fbcdae41e8e72ef9a5cfb5a3f35
Author: Safocl Stollmannovic <safocl88@gmail.com>

> x86: fix duplicate extern declarations
>
> Compiling a kernel module with a C++ compiler results in a duplicate
> echo ‘extern’ specifier error.
> This occurs because the code contains , and
> expands to  when processed by a C++ compiler.
> The  specifier must be removed.
> https://bugzilla.kernel.org/show_bug.cgi?id=222257
>
> Signed-off-by: Safocl Stollmannovic <safocl88@gmail.com>

[Severity: Low]
Was the commit message corrupted by unescaped shell command substitution?
The terms "extern asmlinkage", "asmlinkage", "extern \"C\"", and "extern"
are missing from the sentences, and a stray "echo" appears on the second
line.

Also, is the C++ module rationale accurate here?  The kernel does not
support compiling modules or internal headers with a C++ compiler, and
arch/x86/um/sys_call_table_32.c and arch/x86/um/sys_call_table_64.c are C
translation units rather than headers included by modules.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261113001432.128201-1-safocl88@gmail.com?part=7