ARM: entry: avoid enabling interrupts in prefetch/data abort handlers
Avoid enabling interrupts if the parent context had interrupts enabled
in the abort handler assembly code, and move this into the breakpoint/
page/alignment fault handlers instead.
This gets rid of some special-casing for the breakpoint fault handlers
from the low level abort handler path.
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index 87acc25..a927ca1 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -796,7 +796,7 @@
/*
* Called from either the Data Abort Handler [watchpoint] or the
- * Prefetch Abort Handler [breakpoint] with preemption disabled.
+ * Prefetch Abort Handler [breakpoint] with interrupts disabled.
*/
static int hw_breakpoint_pending(unsigned long addr, unsigned int fsr,
struct pt_regs *regs)
@@ -804,8 +804,10 @@
int ret = 0;
u32 dscr;
- /* We must be called with preemption disabled. */
- WARN_ON(preemptible());
+ preempt_disable();
+
+ if (interrupts_enabled(regs))
+ local_irq_enable();
/* We only handle watchpoints and hardware breakpoints. */
ARM_DBG_READ(c1, 0, dscr);
@@ -824,10 +826,6 @@
ret = 1; /* Unhandled fault. */
}
- /*
- * Re-enable preemption after it was disabled in the
- * low-level exception handling code.
- */
preempt_enable();
return ret;