x86: entry_64.S: delete unused code

A define, two macros and an unreferenced bit of assembly are gone.
Acked-by: Borislav Petkov <bp@suse.de>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Oleg Nesterov <oleg@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andy Lutomirski <luto@amacapital.net>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: X86 ML <x86@kernel.org>
CC: Alexei Starovoitov <ast@plumgrid.com>
CC: Will Drewry <wad@chromium.org>
CC: Kees Cook <keescook@chromium.org>
CC: linux-kernel@vger.kernel.org
Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>

arch/x86/include/asm/calling.h

@@ -83,7 +83,6 @@ For 32-bit we have the following conventions - kernel is built with
 #define SS		160
 
 #define ARGOFFSET	R11
-#define SWFRAME		ORIG_RAX
 
 	.macro SAVE_ARGS addskip=0, save_rcx=1, save_r891011=1, rax_enosys=0
 	subq  $9*8+\addskip, %rsp

arch/x86/kernel/entry_64.S

@@ -155,27 +155,6 @@ ENDPROC(native_usergs_sysret64)
 	movq \tmp,R11+\offset(%rsp)
 	.endm
 
-	.macro FAKE_STACK_FRAME child_rip
-	/* push in order ss, rsp, eflags, cs, rip */
-	xorl %eax, %eax
-	pushq_cfi $__KERNEL_DS /* ss */
-	/*CFI_REL_OFFSET	ss,0*/
-	pushq_cfi %rax /* rsp */
-	CFI_REL_OFFSET	rsp,0
-	pushq_cfi $(X86_EFLAGS_IF|X86_EFLAGS_FIXED) /* eflags - interrupts on */
-	/*CFI_REL_OFFSET	rflags,0*/
-	pushq_cfi $__KERNEL_CS /* cs */
-	/*CFI_REL_OFFSET	cs,0*/
-	pushq_cfi \child_rip /* rip */
-	CFI_REL_OFFSET	rip,0
-	pushq_cfi %rax /* orig rax */
-	.endm
-
-	.macro UNFAKE_STACK_FRAME
-	addq $8*6, %rsp
-	CFI_ADJUST_CFA_OFFSET	-(6*8)
-	.endm
-
 /*
  * initial frame state for interrupts (and exceptions without error code)
  */
@@ -626,19 +605,6 @@ END(\label)
 	FORK_LIKE  vfork
 	FIXED_FRAME stub_iopl, sys_iopl
 
-ENTRY(ptregscall_common)
-	DEFAULT_FRAME 1 8	/* offset 8: return address */
-	RESTORE_TOP_OF_STACK %r11, 8
-	movq_cfi_restore R15+8, r15
-	movq_cfi_restore R14+8, r14
-	movq_cfi_restore R13+8, r13
-	movq_cfi_restore R12+8, r12
-	movq_cfi_restore RBP+8, rbp
-	movq_cfi_restore RBX+8, rbx
-	ret $REST_SKIP		/* pop extended registers */
-	CFI_ENDPROC
-END(ptregscall_common)
-
 ENTRY(stub_execve)
 	CFI_STARTPROC
 	addq $8, %rsp