[PATCH] ARM: decompressor: restore r1 and r2 just before jumping to the kernel

From: Åukasz Stelmach
Date: Wed Apr 04 2018 - 03:47:11 EST


Hypervisor setup before __enter_kernel destroys the value sotred in
r1. The value needs to be restored just before the jump.

Signed-off-by: Åukasz Stelmach <l.stelmach@xxxxxxxxxxx>
---
arch/arm/boot/compressed/head.S | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S
index 182bf6add0b9..517e0e18f0b8 100644
--- a/arch/arm/boot/compressed/head.S
+++ b/arch/arm/boot/compressed/head.S
@@ -561,8 +561,6 @@ not_relocated: mov r0, #0
bl decompress_kernel
bl cache_clean_flush
bl cache_off
- mov r1, r7 @ restore architecture number
- mov r2, r8 @ restore atags pointer

#ifdef CONFIG_ARM_VIRT_EXT
mrs r0, spsr @ Get saved CPU boot mode
@@ -1365,6 +1363,8 @@ __hyp_reentry_vectors:

__enter_kernel:
mov r0, #0 @ must be 0
+ mov r1, r7 @ restore architecture number
+ mov r2, r8 @ restore atags pointer
ARM( mov pc, r4 ) @ call kernel
M_CLASS( add r4, r4, #1 ) @ enter in Thumb mode for M class
THUMB( bx r4 ) @ entry point is always ARM for A/R classes
--
2.11.0