arm64: compat: Remove 32-bit sigreturn code from the vDSO

The sigreturn code in the compat vDSO is unused. Remove it.
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>

arch/arm64/kernel/vdso32/Makefile

@@ -140,7 +140,6 @@ hostprogs := $(munge)
 
 c-obj-vdso := note.o
 c-obj-vdso-gettimeofday := vgettimeofday.o
-asm-obj-vdso := sigreturn.o
 
 ifneq ($(c-gettimeofday-y),)
 VDSO_CFLAGS_gettimeofday_o += -include $(c-gettimeofday-y)

arch/arm64/kernel/vdso32/sigreturn.S

-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * This file provides both A32 and T32 versions, in accordance with the
- * arm sigreturn code.
- *
- * Please read the comments in arch/arm64/kernel/vdso/sigreturn.S to
- * understand some of the craziness in here.
- *
- * Copyright (C) 2018 ARM Limited
- */
-
-#include <linux/linkage.h>
-#include <asm/asm-offsets.h>
-#include <asm/unistd.h>
-
-	.text
-
-	.arm
-	.fnstart
-	.save {r0-r15}
-	.pad #COMPAT_SIGFRAME_REGS_OFFSET
-	nop
-SYM_CODE_START(__kernel_sigreturn_arm)
-	mov r7, #__NR_compat_sigreturn
-	svc #0
-	.fnend
-SYM_CODE_END(__kernel_sigreturn_arm)
-
-	.fnstart
-	.save {r0-r15}
-	.pad #COMPAT_RT_SIGFRAME_REGS_OFFSET
-	nop
-SYM_CODE_START(__kernel_rt_sigreturn_arm)
-	mov r7, #__NR_compat_rt_sigreturn
-	svc #0
-	.fnend
-SYM_CODE_END(__kernel_rt_sigreturn_arm)
-
-	.thumb
-	.fnstart
-	.save {r0-r15}
-	.pad #COMPAT_SIGFRAME_REGS_OFFSET
-	nop
-SYM_CODE_START(__kernel_sigreturn_thumb)
-	mov r7, #__NR_compat_sigreturn
-	svc #0
-	.fnend
-SYM_CODE_END(__kernel_sigreturn_thumb)
-
-	.fnstart
-	.save {r0-r15}
-	.pad #COMPAT_RT_SIGFRAME_REGS_OFFSET
-	nop
-SYM_CODE_START(__kernel_rt_sigreturn_thumb)
-	mov r7, #__NR_compat_rt_sigreturn
-	svc #0
-	.fnend
-SYM_CODE_END(__kernel_rt_sigreturn_thumb)

arch/arm64/kernel/vdso32/vdso.lds.S

@@ -64,19 +64,7 @@ VERSION
 		__vdso_clock_gettime;
 		__vdso_gettimeofday;
 		__vdso_clock_getres;
-		__kernel_sigreturn_arm;
-		__kernel_sigreturn_thumb;
-		__kernel_rt_sigreturn_arm;
-		__kernel_rt_sigreturn_thumb;
 		__vdso_clock_gettime64;
 	local: *;
 	};
 }
-
-/*
- * Make the sigreturn code visible to the kernel.
- */
-VDSO_compat_sigreturn_arm	= __kernel_sigreturn_arm;
-VDSO_compat_sigreturn_thumb	= __kernel_sigreturn_thumb;
-VDSO_compat_rt_sigreturn_arm	= __kernel_rt_sigreturn_arm;
-VDSO_compat_rt_sigreturn_thumb	= __kernel_rt_sigreturn_thumb;