[tip:perf/core] perf/core: Do error out on a kernel filter on an exclude_filter event

[tip-bot for Alexander Shishkin]

Commit-ID:  9ccbfbb157a38921702402281ca7be530b4c3669
Gitweb:     http://git.kernel.org/tip/9ccbfbb157a38921702402281ca7be530b4c3669
Author:     Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
AuthorDate: Thu, 26 Jan 2017 11:40:56 +0200
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Fri, 10 Feb 2017 09:08:09 +0100

perf/core: Do error out on a kernel filter on an exclude_filter event

It is currently possible to configure a kernel address filter for a
event that excludes kernel from its traces (attr.exclude_kernel==1).

While in reality this doesn't make sense, the SET_FILTER ioctl() should
return a error in such case, currently it does not. Furthermore, it
will still silently discard the filter and any potentially valid filters
that came with it.

This patch makes the SET_FILTER ioctl() error out in such cases.

Signed-off-by: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Vince Weaver <vincent.weaver@xxxxxxxxx>
Cc: Will Deacon <will.deacon@xxxxxxx>
Cc: vince@xxxxxxxxxx
Link: http://lkml.kernel.org/r/20170126094057.13805-3-alexander.shishkin@xxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 kernel/events/core.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 88676ff..1730995 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8260,6 +8260,7 @@ perf_event_parse_addr_filter(struct perf_event *event, char *fstr,
 		 * attribute.
 		 */
 		if (state == IF_STATE_END) {
+			ret = -EINVAL;
 			if (kernel && event->attr.exclude_kernel)
 				goto fail;