diff mbox series

perf/arm-cmn: Validate cycles events fully

Message ID 3124e8c276a1f513c1a415dc839ca4181b3c8bc8.1680522545.git.robin.murphy@arm.com
State New
Headers
Series perf/arm-cmn: Validate cycles events fully |

Commit Message

Robin Murphy April 3, 2023, 11:49 a.m. UTC 
  DTC cycle count events don't have anything to validate or initialise in
themselves, but we should not forget to still validate their whole group
context. Otherwise, we may fail to correctly reject a contrived group
containing an impossible number of cycles events.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
---
 drivers/perf/arm-cmn.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Ilkka Koskinen April 4, 2023, 6:05 a.m. UTC | #1 
On Mon, 3 Apr 2023, Robin Murphy wrote:
> DTC cycle count events don't have anything to validate or initialise in
> themselves, but we should not forget to still validate their whole group
> context. Otherwise, we may fail to correctly reject a contrived group
> containing an impossible number of cycles events.
>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>

Looks good to me and works as expected.

Cheers, Ilkka

> ---
> drivers/perf/arm-cmn.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
> index 367d41c5d983..45819528facb 100644
> --- a/drivers/perf/arm-cmn.c
> +++ b/drivers/perf/arm-cmn.c
> @@ -1558,7 +1558,7 @@ static int arm_cmn_event_init(struct perf_event *event)
> 	type = CMN_EVENT_TYPE(event);
> 	/* DTC events (i.e. cycles) already have everything they need */
> 	if (type == CMN_TYPE_DTC)
> -		return 0;
> +		return arm_cmn_validate_group(cmn, event);
>
> 	eventid = CMN_EVENT_EVENTID(event);
> 	/* For watchpoints we need the actual XP node here */
> -- 
> 2.39.2.101.g768bb238c484.dirty
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>
Will Deacon April 6, 2023, 3:51 p.m. UTC | #2 
On Mon, 3 Apr 2023 12:49:05 +0100, Robin Murphy wrote:
> DTC cycle count events don't have anything to validate or initialise in
> themselves, but we should not forget to still validate their whole group
> context. Otherwise, we may fail to correctly reject a contrived group
> containing an impossible number of cycles events.
> 
> 

Applied to will (for-next/perf), thanks!

[1/1] perf/arm-cmn: Validate cycles events fully
      https://git.kernel.org/will/c/23b2fd839489

Cheers,
diff mbox series

Patch

diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c
index 367d41c5d983..45819528facb 100644
--- a/drivers/perf/arm-cmn.c
+++ b/drivers/perf/arm-cmn.c
@@ -1558,7 +1558,7 @@  static int arm_cmn_event_init(struct perf_event *event)
 	type = CMN_EVENT_TYPE(event);
 	/* DTC events (i.e. cycles) already have everything they need */
 	if (type == CMN_TYPE_DTC)
-		return 0;
+		return arm_cmn_validate_group(cmn, event);
 
 	eventid = CMN_EVENT_EVENTID(event);
 	/* For watchpoints we need the actual XP node here */