perf/core: Allow kernel address filter when not filtering the kernel

The so-called 'kernel' address filter can also be useful for filtering
fixed addresses in user space.  Allow that.

Signed-off-by: Adrian Hunter <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: ahunter6

kernel/events/core.c

@@ -10515,8 +10515,6 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
 		 */
 		if (state == IF_STATE_END) {
 			ret = -EINVAL;
-			if (kernel && event->attr.exclude_kernel)
-				goto fail;
 
 			/*
 			 * ACTION "filter" must have a non-zero length region