On Fri, 28 Oct 2022 18:31:49 -0400 Steven Rostedt wrote: > Could someone from networking confirm (or deny) that the timer being > removed in sk_stop_timer() will no longer be used even if del_timer() > returns false? > > net/core/sock.c: > > void sk_stop_timer(struct sock *sk, struct timer_list* timer) > { > if (del_timer(timer)) > __sock_put(sk); > } > > If this is the case, then I'll add the following interface: > > del_timer_sync_shutdown() // the common case which syncs > > del_timer_shutdown() // the uncommon case, that returns immediately > // used for those cases that add extra code to > // handle it, like sk_stop_timer() Sorry too many bugs at once :) FWIW Paolo was saying privately earlier today that he spotted some cases of reuse, he gave an example of ccid2_hc_tx_packet_recv() So we can't convert all cases of sk_stop_timer() in one fell swoop :( > Which has the same semantics as del_timer_sync() and del_timer() > respectively, but will prevent the timer from being rearmed again. > > This way we can convert the sk_stop_timer() to: > > void sk_stop_timer(struct sock *sk, struct timer_list* timer) > { > if (del_timer_shutdown(timer)) > __sock_put(sk); > } > > > We can also add the del_timer_shutdown() to other locations that need to > put a timer into a shutdown state before freeing, and where it's in a > context that can not call del_timer_sync_shutdown().