Only update psock->saved_* if psock->sk_proto has not been initialized yet. This allows us to get rid of tcp_bpf_reinit_sk_prot.
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| @@ -347,11 +347,23 @@ static inline void sk_psock_update_proto(struct sock *sk, · 346 unmodified lines | ||
| 347 | 347 | struct sk_psock *psock, |
| 348 | 348 | struct proto *ops) |
| 349 | 349 | { |
| 350 | − psock->saved_unhash = sk->sk_prot->unhash; | |
| 351 | − psock->saved_close = sk->sk_prot->close; | |
| 352 | − psock->saved_write_space = sk->sk_write_space; | |
| 350 | + /* Initialize saved callbacks and original proto only once, since this | |
| 351 | + * function may be called multiple times for a psock, e.g. when | |
| 352 | + * psock->progs.msg_parser is updated. | |
| 353 | + * | |
| 354 | + * Since we've not installed the new proto, psock is not yet in use and | |
| 355 | + * we can initialize it without synchronization. | |
| 356 | + */ | |
| 357 | + if (!psock->sk_proto) { | |
| 358 | + struct proto *orig = READ_ONCE(sk->sk_prot); | |
| 359 | + | |
| 360 | + psock->saved_unhash = orig->unhash; | |
| 361 | + psock->saved_close = orig->close; | |
| 362 | + psock->saved_write_space = sk->sk_write_space; | |
| 363 | + | |
| 364 | + psock->sk_proto = orig; | |
| 365 | + } | |
| 353 | 366 | |
| 354 | − psock->sk_proto = sk->sk_prot; | |
| 355 | 367 | /* Pairs with lockless read in sk_clone_lock() */ |
| 356 | 368 | WRITE_ONCE(sk->sk_prot, ops); |
| 357 | 369 | } |