ARC: entry: fix syscall_trace_exit argument

stable inclusion
from stable-v5.10.113
commit 5580b974a84b30f6da90a3a562ea0dbfb0038110
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5ISAH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=5580b974a84b30f6da90a3a562ea0dbfb0038110

--------------------------------

commit b1c6ecfd upstream.

Function syscall_trace_exit expects pointer to pt_regs. However
r0 is also used to keep syscall return value. Restore pointer
to pt_regs before calling syscall_trace_exit.

Cc: <stable@vger.kernel.org>
Signed-off-by: NSergey Matyukevich <sergey.matyukevich@synopsys.com>
Signed-off-by: NVineet Gupta <vgupta@kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>
Acked-by: NXie XiuQi <xiexiuqi@huawei.com>

arch/arc/kernel/entry.S

@@ -199,6 +199,7 @@ tracesys_exit:
 	st  r0, [sp, PT_r0]     ; sys call return value in pt_regs
 
 	;POST Sys Call Ptrace Hook
+	mov r0, sp		; pt_regs needed
 	bl  @syscall_trace_exit
 	b   ret_from_exception ; NOT ret_from_system_call at is saves r0 which
 	; we'd done before calling post hook above