[PATCH 5.4 013/134] csky: Fixup abiv2 syscall_trace break a4 & a5

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

From: Guo Ren <guoren@linux.alibaba.com>

[ Upstream commit e0bbb53843b5fdfe464b099217e3b9d97e8a75d7 ]

Current implementation could destory a4 & a5 when strace, so we need to get them
from pt_regs by SAVE_ALL.

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/csky/abiv2/inc/abi/entry.h | 2 ++
 arch/csky/kernel/entry.S        | 6 ++++--
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/arch/csky/abiv2/inc/abi/entry.h b/arch/csky/abiv2/inc/abi/entry.h
index 9023828ede97..ac8f65a3e75a 100644
--- a/arch/csky/abiv2/inc/abi/entry.h
+++ b/arch/csky/abiv2/inc/abi/entry.h
@@ -13,6 +13,8 @@
 #define LSAVE_A1	28
 #define LSAVE_A2	32
 #define LSAVE_A3	36
+#define LSAVE_A4	40
+#define LSAVE_A5	44
 
 #define KSPTOUSP
 #define USPTOKSP
diff --git a/arch/csky/kernel/entry.S b/arch/csky/kernel/entry.S
index 65c55f22532a..4349528fbf38 100644
--- a/arch/csky/kernel/entry.S
+++ b/arch/csky/kernel/entry.S
@@ -170,8 +170,10 @@ csky_syscall_trace:
 	ldw	a3, (sp, LSAVE_A3)
 #if defined(__CSKYABIV2__)
 	subi	sp, 8
-	stw	r5, (sp, 0x4)
-	stw	r4, (sp, 0x0)
+	ldw	r9, (sp, LSAVE_A4)
+	stw	r9, (sp, 0x0)
+	ldw	r9, (sp, LSAVE_A5)
+	stw	r9, (sp, 0x4)
 #else
 	ldw	r6, (sp, LSAVE_A4)
 	ldw	r7, (sp, LSAVE_A5)
-- 
2.25.1