x86/entry/32: Remove asmlinkage_protect()

Now that syscalls are called from C code, which copies the args to
new stack slots instead of overlaying pt_regs, asmlinkage_protect()
is no longer needed.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Acked-by: Andy Lutomirski <luto@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1462416278-11974-4-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h
index 79327e9..0ccb26d 100644 (file)
--- a/arch/x86/include/asm/linkage.h
+++ b/arch/x86/include/asm/linkage.h
@@ -8,40 +8,6 @@
 
 #ifdef CONFIG_X86_32
 #define asmlinkage CPP_ASMLINKAGE __attribute__((regparm(0)))
-
-/*
- * Make sure the compiler doesn't do anything stupid with the
- * arguments on the stack - they are owned by the *caller*, not
- * the callee. This just fools gcc into not spilling into them,
- * and keeps it from doing tailcall recursion and/or using the
- * stack slots for temporaries, since they are live and "used"
- * all the way to the end of the function.
- *
- * NOTE! On x86-64, all the arguments are in registers, so this
- * only matters on a 32-bit kernel.
- */
-#define asmlinkage_protect(n, ret, args...) \
-       __asmlinkage_protect##n(ret, ##args)
-#define __asmlinkage_protect_n(ret, args...) \
-       __asm__ __volatile__ ("" : "=r" (ret) : "0" (ret), ##args)
-#define __asmlinkage_protect0(ret) \
-       __asmlinkage_protect_n(ret)
-#define __asmlinkage_protect1(ret, arg1) \
-       __asmlinkage_protect_n(ret, "m" (arg1))
-#define __asmlinkage_protect2(ret, arg1, arg2) \
-       __asmlinkage_protect_n(ret, "m" (arg1), "m" (arg2))
-#define __asmlinkage_protect3(ret, arg1, arg2, arg3) \
-       __asmlinkage_protect_n(ret, "m" (arg1), "m" (arg2), "m" (arg3))
-#define __asmlinkage_protect4(ret, arg1, arg2, arg3, arg4) \
-       __asmlinkage_protect_n(ret, "m" (arg1), "m" (arg2), "m" (arg3), \
-                             "m" (arg4))
-#define __asmlinkage_protect5(ret, arg1, arg2, arg3, arg4, arg5) \
-       __asmlinkage_protect_n(ret, "m" (arg1), "m" (arg2), "m" (arg3), \
-                             "m" (arg4), "m" (arg5))
-#define __asmlinkage_protect6(ret, arg1, arg2, arg3, arg4, arg5, arg6) \
-       __asmlinkage_protect_n(ret, "m" (arg1), "m" (arg2), "m" (arg3), \
-                             "m" (arg4), "m" (arg5), "m" (arg6))
-
 #endif /* CONFIG_X86_32 */
 
 #ifdef __ASSEMBLY__