[PATCH Dovetail v3 2/6] arm: irq_pipeline: Fix dovetail_fault_{entry,exit} bypass in do_kernel_address_page_fault

In case do_kernel_address_page_fault() was entered over supervisor mode
the dovetail_fault_{entry,exit} machinery was bypassed. As a result the
inband IRQ mask might have been touched from the oob stage.

There is another problem with interrupts_enabled() in the supervisor
mode code path. That one will be addressed in a separate patch.

Signed-off-by: Florian Bezdeka <[email protected]>
---
 arch/arm/mm/fault.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c
index b6b766652b753ef860d16b153685b0d3b582bffa..08ebc043971000fd8d6245bcbb6c170d801c73b3 100644
--- a/arch/arm/mm/fault.c
+++ b/arch/arm/mm/fault.c
@@ -332,6 +332,7 @@ do_kernel_address_page_fault(struct mm_struct *mm, unsigned long addr,
 		__do_user_fault(addr, fsr, SIGSEGV, SEGV_MAPERR, regs);
 		dovetail_fault_exit(ARM_TRAP_ACCESS, regs, irqflags);
 	} else {
+		irqflags = dovetail_fault_entry(ARM_TRAP_ACCESS, regs);
 		/*
 		 * Fault from kernel mode. Enable interrupts if they were
 		 * enabled in the parent context. Section (upper page table)
@@ -344,6 +345,8 @@ do_kernel_address_page_fault(struct mm_struct *mm, unsigned long addr,
 			local_irq_enable();
 
 		__do_kernel_fault(mm, addr, fsr, regs);
+
+		dovetail_fault_exit(ARM_TRAP_ACCESS, regs, irqflags);
 	}
 
 	return 0;

-- 
2.54.0