diff options
| author | Syed Rameez Mustafa <rameezmustafa@codeaurora.org> | 2016-10-24 18:37:14 -0700 |
|---|---|---|
| committer | Syed Rameez Mustafa <rameezmustafa@codeaurora.org> | 2016-10-24 18:44:02 -0700 |
| commit | 5c647926d044993f9ded013d4531a373e6fcbc1e (patch) | |
| tree | e949e0a09b2d6c108b13d359c708e294d0784ca3 /kernel | |
| parent | 46aa49c1188a77f52dc4969f82292c176d8f399b (diff) | |
sched: Set curr/prev_window_cpu pointers to NULL in sched_exit()
trace_sched_update_task_ravg relies on NULL pointers to ensure that
it doesn't access them. Make sure that when a task exits, these
pointers are set to NULL. Otherwise any call to update_task_ravg()
between sched_exit() and releasing the task structure will access
bogus pointers. In some cases those memory locations are unmapped
and cause a kernel panic.
Change-Id: I9eebb4fb35aca2c8424bfb29ae9d833650dc5ad4
Signed-off-by: Syed Rameez Mustafa <rameezmustafa@codeaurora.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/sched/core.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 53f7b50b7541..c07d844c576e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2273,6 +2273,14 @@ void sched_exit(struct task_struct *p) kfree(p->ravg.curr_window_cpu); kfree(p->ravg.prev_window_cpu); + /* + * update_task_ravg() can be called for exiting tasks. While the + * function itself ensures correct behavior, the corresponding + * trace event requires that these pointers be NULL. + */ + p->ravg.curr_window_cpu = NULL; + p->ravg.prev_window_cpu = NULL; + enqueue_task(rq, p, 0); clear_ed_task(p, rq); task_rq_unlock(rq, p, &flags); |