arm64: scs: Drop unused 'tmp' argument to scs_{load, save} asm macros

The scs_load and scs_save asm macros don't make use of the mandatory
'tmp' register argument, so drop it and fix up the callers.

Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/r/20210527105529.21967-1-will@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>

Author: willdeacon

arch/arm64/include/asm/scs.h

@@ -9,18 +9,18 @@
 #ifdef CONFIG_SHADOW_CALL_STACK
 	scs_sp	.req	x18
 
-	.macro scs_load tsk, tmp
+	.macro scs_load tsk
 	ldr	scs_sp, [\tsk, #TSK_TI_SCS_SP]
 	.endm
 
-	.macro scs_save tsk, tmp
+	.macro scs_save tsk
 	str	scs_sp, [\tsk, #TSK_TI_SCS_SP]
 	.endm
 #else
-	.macro scs_load tsk, tmp
+	.macro scs_load tsk
 	.endm
 
-	.macro scs_save tsk, tmp
+	.macro scs_save tsk
 	.endm
 #endif /* CONFIG_SHADOW_CALL_STACK */
 

arch/arm64/kernel/entry.S

@@ -275,7 +275,7 @@ alternative_else_nop_endif
 
 	mte_set_kernel_gcr x22, x23
 
-	scs_load tsk, x20
+	scs_load tsk
 	.else
 	add	x21, sp, #PT_REGS_SIZE
 	get_current_task tsk
@@ -375,7 +375,7 @@ alternative_if ARM64_WORKAROUND_845719
 alternative_else_nop_endif
 #endif
 3:
-	scs_save tsk, x0
+	scs_save tsk
 
 #ifdef CONFIG_ARM64_PTR_AUTH
 alternative_if ARM64_HAS_ADDRESS_AUTH
@@ -979,8 +979,8 @@ SYM_FUNC_START(cpu_switch_to)
 	mov	sp, x9
 	msr	sp_el0, x1
 	ptrauth_keys_install_kernel x1, x8, x9, x10
-	scs_save x0, x8
-	scs_load x1, x8
+	scs_save x0
+	scs_load x1
 	ret
 SYM_FUNC_END(cpu_switch_to)
 NOKPROBE(cpu_switch_to)

arch/arm64/kernel/head.S

@@ -412,7 +412,7 @@ SYM_FUNC_END(__create_page_tables)
 	stp	xzr, xzr, [sp, #S_STACKFRAME]
 	add	x29, sp, #S_STACKFRAME
 
-	scs_load \tsk, \tmp1
+	scs_load \tsk
 
 	adr_l	\tmp1, __per_cpu_offset
 	ldr	w\tmp2, [\tsk, #TSK_CPU]