Steven Rostedt wrote:

On Tue, 18 Jun 2019 20:17:04 +0530
"Naveen N. Rao" [off-list ref] wrote:

quoted

@@ -1551,7 +1551,7 @@ unsigned long ftrace_location_range(unsigned long start, unsigned long end)
 	key.flags = end;	/* overload flags, as it is unsigned long */
 
 	for (pg = ftrace_pages_start; pg; pg = pg->next) {
-		if (end < pg->records[0].ip ||
+		if (end <= pg->records[0].ip ||

This breaks the algorithm. "end" is inclusive. That is, if you look for
a single byte, where "start" and "end" are the same, and it happens to
be the first ip on the pg page, it will be skipped, and not found.

Thanks. It looks like I should be over-riding ftrace_location() instead.  
I will update this patch.

- Naveen