On 4/25/21 12:26 AM, Stefan Metzmacher wrote: > Signed-off-by: Stefan Metzmacher <metze@xxxxxxxxx> > --- > fs/io-wq.c | 14 +++++++++++++- > 1 file changed, 13 insertions(+), 1 deletion(-) > > diff --git a/fs/io-wq.c b/fs/io-wq.c > index cd1af924c3d1..b80c5d905127 100644 > --- a/fs/io-wq.c > +++ b/fs/io-wq.c > @@ -640,7 +640,19 @@ static void create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index) > return; > } > > - snprintf(tsk_comm, sizeof(tsk_comm), "iou-wrk-%d", wq->task->pid); > + /* > + * The limit value of pid_max_max/PID_MAX_LIMIT > + * is 4 * 1024 * 1024 = 4194304. > + * > + * TASK_COMM_LEN is 16, so we have 15 chars to fill. > + * > + * With "iou-wrk-4194304" we just fit into 15 chars. > + * If that ever changes we may better add some special > + * handling for PF_IO_WORKER in proc_task_name(), as that > + * allows up to 63 chars. > + */ > + WARN_ON(snprintf(tsk_comm, sizeof(tsk_comm), > + "iou-wrk-%d", wq->task->pid) >= sizeof(tsk_comm)); We don't really care, so saner would be to just to leave them and don't warn. Not see much need but can be something like "iou-wrk-00000*" if overflowed. Same for 6/6. > set_task_comm(tsk, tsk_comm); > > tsk->pf_io_worker = worker; > -- Pavel Begunkov
