From 54e1b51f5b34e54059822a637dcdc842e48c11e3 Mon Sep 17 00:00:00 2001
From: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Date: Tue, 3 Apr 2018 10:44:32 -0700
Subject: [PATCH] FROMLIST: arm64: kernel: avoid x18 in __cpu_soft_restart

The code in __cpu_soft_restart() uses x18 as an arbitrary temp register,
which will shortly be disallowed. So use x8 instead.

Bug: 145210207
Change-Id: Ifeb90566b4e41eb376fd4beaffd55fca8597aa2c
(am from https://lore.kernel.org/patchwork/patch/1149053/)
Link: https://patchwork.kernel.org/patch/9836877/
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
[Sami: updated commit message]
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
 arch/arm64/kernel/cpu-reset.S | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S
index 8021b46c9743..63ccd07d994b 100644
--- a/arch/arm64/kernel/cpu-reset.S
+++ b/arch/arm64/kernel/cpu-reset.S
@@ -45,11 +45,11 @@ ENTRY(__cpu_soft_restart)
 	mov	x0, #HVC_SOFT_RESTART
 	hvc	#0				// no return
 
-1:	mov	x18, x1				// entry
+1:	mov	x8, x1				// entry
 	mov	x0, x2				// arg0
 	mov	x1, x3				// arg1
 	mov	x2, x4				// arg2
-	br	x18
+	br	x8
 ENDPROC(__cpu_soft_restart)
 
 .popsection