From f8781c4a226319fe60e652118b90cf094ccfe747 Mon Sep 17 00:00:00 2001
From: Dominik Brodowski <linux@dominikbrodowski.net>
Date: Thu, 5 Apr 2018 11:53:05 +0200
Subject: syscalls/x86: Unconditionally enable 'struct pt_regs' based syscalls
 on x86_64

Removing CONFIG_SYSCALL_PTREGS from arch/x86/Kconfig and simply selecting
ARCH_HAS_SYSCALL_WRAPPER unconditionally on x86-64 allows us to simplify
several codepaths.

Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20180405095307.3730-7-linux@dominikbrodowski.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/include/asm/syscall.h  |  4 ++--
 arch/x86/include/asm/syscalls.h | 20 ++++----------------
 2 files changed, 6 insertions(+), 18 deletions(-)

(limited to 'arch/x86/include/asm')

diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h
index 17c62373a6f9..d653139857af 100644
--- a/arch/x86/include/asm/syscall.h
+++ b/arch/x86/include/asm/syscall.h
@@ -20,13 +20,13 @@
 #include <asm/thread_info.h>	/* for TS_COMPAT */
 #include <asm/unistd.h>
 
-#ifdef CONFIG_SYSCALL_PTREGS
+#ifdef CONFIG_X86_64
 typedef asmlinkage long (*sys_call_ptr_t)(const struct pt_regs *);
 #else
 typedef asmlinkage long (*sys_call_ptr_t)(unsigned long, unsigned long,
 					  unsigned long, unsigned long,
 					  unsigned long, unsigned long);
-#endif /* CONFIG_SYSCALL_PTREGS */
+#endif /* CONFIG_X86_64 */
 extern const sys_call_ptr_t sys_call_table[];
 
 #if defined(CONFIG_X86_32)
diff --git a/arch/x86/include/asm/syscalls.h b/arch/x86/include/asm/syscalls.h
index e4ad93c05f02..d4d18d94695c 100644
--- a/arch/x86/include/asm/syscalls.h
+++ b/arch/x86/include/asm/syscalls.h
@@ -19,10 +19,10 @@
 /* kernel/ioport.c */
 long ksys_ioperm(unsigned long from, unsigned long num, int turn_on);
 
-#ifndef CONFIG_SYSCALL_PTREGS
-/*
- * If CONFIG_SYSCALL_PTREGS is enabled, a different syscall calling convention
- * is used. Do not include these -- invalid -- prototypes then
+#ifdef CONFIG_X86_32
+/* 
+ * These definitions are only valid on pure 32-bit systems; x86-64 uses a
+ * different syscall calling convention
  */
 asmlinkage long sys_ioperm(unsigned long, unsigned long, int);
 asmlinkage long sys_iopl(unsigned int);
@@ -38,7 +38,6 @@ asmlinkage long sys_set_thread_area(struct user_desc __user *);
 asmlinkage long sys_get_thread_area(struct user_desc __user *);
 
 /* X86_32 only */
-#ifdef CONFIG_X86_32
 
 /* kernel/signal.c */
 asmlinkage long sys_sigreturn(void);
@@ -48,16 +47,5 @@ struct vm86_struct;
 asmlinkage long sys_vm86old(struct vm86_struct __user *);
 asmlinkage long sys_vm86(unsigned long, unsigned long);
 
-#else /* CONFIG_X86_32 */
-
-/* X86_64 only */
-/* kernel/process_64.c */
-asmlinkage long sys_arch_prctl(int, unsigned long);
-
-/* kernel/sys_x86_64.c */
-asmlinkage long sys_mmap(unsigned long, unsigned long, unsigned long,
-			 unsigned long, unsigned long, unsigned long);
-
 #endif /* CONFIG_X86_32 */
-#endif /* CONFIG_SYSCALL_PTREGS */
 #endif /* _ASM_X86_SYSCALLS_H */
-- 
cgit