[PATCH 65/78] ARM: aarch64: implement ignoring data aborts

[Sascha Hauer]

Data aborts can be masked using the data_abort_mask() function.
Add the missing pieces for functionality on aarch64 so that the
'md' command is safe to call even with faulting addresses.

Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
---
 arch/arm/cpu/interrupts_64.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/arm/cpu/interrupts_64.c b/arch/arm/cpu/interrupts_64.c
index ee3dc3380b..32c8dfcb2d 100644
--- a/arch/arm/cpu/interrupts_64.c
+++ b/arch/arm/cpu/interrupts_64.c
@@ -143,8 +143,18 @@ void do_bad_error(struct pt_regs *pt_regs)
 	do_exception(pt_regs);
 }
 
+extern volatile int arm_ignore_data_abort;
+extern volatile int arm_data_abort_occurred;
+
 void do_sync(struct pt_regs *pt_regs, unsigned int esr, unsigned long far)
 {
+	if ((esr >> ESR_ELx_EC_SHIFT) == ESR_ELx_EC_DABT_CUR &&
+			arm_ignore_data_abort) {
+		arm_data_abort_occurred = 1;
+		pt_regs->elr += 4;
+		return;
+	}
+
 	printf("%s exception at 0x%016lx\n", esr_get_class_string(esr), far);
 	do_exception(pt_regs);
 }
@@ -156,9 +166,6 @@ void do_error(struct pt_regs *pt_regs)
 	do_exception(pt_regs);
 }
 
-extern volatile int arm_ignore_data_abort;
-extern volatile int arm_data_abort_occurred;
-
 void data_abort_mask(void)
 {
 	arm_data_abort_occurred = 0;
-- 
2.16.1