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Subject[PATCH 3/9] arm64: entry: record the hardirq changes on the entry/exit code
Date
Just as the arm32 code does, record the hardirq changes at the entry/exit
code.

The trace code may changes some registers, but the syscall path
needs the x0 ~ x7, we restore them in the el0_svc_naked.

Signed-off-by: Huang Shijie <shijie.huang@arm.com>
---
arch/arm64/kernel/entry.S | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S
index 21b6068..4c67c56 100644
--- a/arch/arm64/kernel/entry.S
+++ b/arch/arm64/kernel/entry.S
@@ -132,6 +132,15 @@
mov scno, x8
.endif

+#ifdef CONFIG_TRACE_IRQFLAGS
+ /*
+ * The trace_hardirqs_off may changes some registers, so we should
+ * restore them back from the stack in the necessary place, such as
+ * el0_svc_naked.
+ */
+ bl trace_hardirqs_off
+#endif
+
/*
* Registers that may be useful after this macro is invoked:
*
@@ -142,6 +151,9 @@
.endm

.macro kernel_exit, el
+#ifdef CONFIG_TRACE_IRQFLAGS
+ bl trace_hardirqs_on
+#endif
ldp x21, x22, [sp, #S_PC] // load ELR, SPSR
.if \el == 0
ct_user_enter
@@ -729,6 +741,9 @@ el0_svc:
uxtw scno, w26 // syscall number in w8
mov sc_nr, #__NR_syscalls
el0_svc_naked: // compat entry point
+#ifdef CONFIG_TRACE_IRQFLAGS
+ restore_syscall_regs
+#endif
stp x19, scno, [sp, #S_ORIG_X0] // save the original x0 and syscall number
enable_dbg_and_irq
ct_user_exit 1
--
2.5.5
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