On Thu, Jun 10, 2010 at 10:40:24PM +1000, Paul Mackerras wrote:

On Wed, Jun 09, 2010 at 03:55:59PM +0530, K.Prasad wrote:

quoted

+	if (!((bp->attr.bp_addr <= dar) &&
+	     (dar <= (bp->attr.bp_addr + bp->attr.bp_len)))) {
+		/*
+		 * This exception is triggered not because of a memory access
+		 * on the monitored variable but in the double-word address
+		 * range in which it is contained. We will consume this
+		 * exception, considering it as 'noise'.
+		 */
+		info->extraneous_interrupt = true;
+	}

Ummm, don't you need to add "else info->extraneous_interrupt = false;"
here?  I don't see anywhere that you ever clear it otherwise.

Also, I think you need to do the "if (!info->extraneous_interrupt)"
check around the call to perf_bp_event() later on in
hw_breakpoint_handler() as well as around the call in
single_step_dabr_instruction().

Paul.

True, I've added the check before perf_bp_event() (wherever it was
missing before) in the patchset ver XXIV.

Thanks,
K.Prasad