3.2.87-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
commit a06393ed03167771246c4c43192d9c264bc48412 upstream.
When removing a bcm tx operation either a hrtimer or a tasklet might run.
As the hrtimer triggers its associated tasklet and vice versa we need to
take care to mutually terminate both handlers.
Reported-by: Michael Josenhans <michael.josenhans@xxxxxx>
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Tested-by: Michael Josenhans <michael.josenhans@xxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
net/can/bcm.c | 23 ++++++++++++++++-------
1 file changed, 16 insertions(+), 7 deletions(-)
--- a/net/can/bcm.c
+++ b/net/can/bcm.c
@@ -702,14 +702,23 @@ static struct bcm_op *bcm_find_op(struct
static void bcm_remove_op(struct bcm_op *op)
{
- hrtimer_cancel(&op->timer);
- hrtimer_cancel(&op->thrtimer);
+ if (op->tsklet.func) {
+ while (test_bit(TASKLET_STATE_SCHED, &op->tsklet.state) ||
+ test_bit(TASKLET_STATE_RUN, &op->tsklet.state) ||
+ hrtimer_active(&op->timer)) {
+ hrtimer_cancel(&op->timer);
+ tasklet_kill(&op->tsklet);
+ }
+ }
- if (op->tsklet.func)
- tasklet_kill(&op->tsklet);
-
- if (op->thrtsklet.func)
- tasklet_kill(&op->thrtsklet);
+ if (op->thrtsklet.func) {
+ while (test_bit(TASKLET_STATE_SCHED, &op->thrtsklet.state) ||
+ test_bit(TASKLET_STATE_RUN, &op->thrtsklet.state) ||
+ hrtimer_active(&op->thrtimer)) {
+ hrtimer_cancel(&op->thrtimer);
+ tasklet_kill(&op->thrtsklet);
+ }
+ }
if ((op->frames) && (op->frames != &op->sframe))
kfree(op->frames);