On 1/17/25 5:58 PM, Jason Xing wrote:
On 1/15/25 5:12 PM, Jason Xing wrote:
Also, I need to set allow_direct_access to one as long as there is
"sock_ops.is_fullsock = 1;" in the existing callbacks.
Only set allow_direct_access when the sk is fullsock in the "existing" sockops
callback.
Only "existing"? Then how can the bpf program access those members of
the tcp socket structure in the current/new timestamping callbacks?
There is at least one sk write:
case offsetof(struct bpf_sock_ops, sk_txhash):
SOCK_OPS_GET_OR_SET_FIELD(sk_txhash, sk_txhash,
struct sock, type);
afaict, the kernel always writes sk->sk_txhash with the sk lock held. The new
timestamping callbacks cannot write because it does not hold the lock.
Surely, I will handle the sk_txhash case as you suggested 🙂
to be clear, not setting the allow_tcp_access in the new timestamping cb should do.
