[PATCH 7/9] arm64: entry: save the x0 back into the stack before disabling the interrupt

From: Huang Shijie
Date: Sun May 29 2016 - 22:54:34 EST


We will add the hardirq flags trace code in the disable_irq, the trace
code may changes the x0, so save the x0 back into the stack before
disabling the interrupt,

This patch makes preparation for the later patch.

Signed-off-by: Huang Shijie <shijie.huang@xxxxxxx>
---
arch/arm64/kernel/entry.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 63bf7ad..7005789 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -672,8 +672,8 @@ ENDPROC(cpu_switch_to)
* and this includes saving x0 back into the kernel stack.
*/
ret_fast_syscall:
- disable_irq // disable interrupts
str x0, [sp, #S_X0] // returned x0
+ disable_irq // disable interrupts
ldr x1, [tsk, #TI_FLAGS] // re-check for syscall tracing
and x2, x1, #_TIF_SYSCALL_WORK
cbnz x2, ret_fast_syscall_trace
--
2.5.5