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Subject: RE: [PATCH net-next 6/7] net: stmmac: Enable RX via AF_XDP zero-copy
Thread-Topic: [PATCH net-next 6/7] net: stmmac: Enable RX via AF_XDP zero-copy
Thread-Index: AQHXL7HKyqleeMWQYU2lo3HbR6/Cf6qxY5gAgACwS2A=
Date:   Tue, 13 Apr 2021 07:58:14 +0000
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>+	/* synchronize_rcu() needed for pending XDP buffers to drain */
>+	for (queue =3D 0; queue < rx_queues_cnt; queue++) {
>+		rx_q =3D &priv->rx_queue[queue];
>+		if (rx_q->xsk_pool) {
>+			synchronize_rcu();
>
>Are you sure this is safe here, especially via the ->ndo_setup_tc() code p=
ath?
>
Thanks for the feedback.
Will fix this in v2 by introducing below:

Introduce __stmmac_disable_all_queues() to contain the original code that
does napi_disable() and then make stmmac_setup_tc_block_cb(0 to call this.

Add stmmac_disable_all_queues() to perform synchronize_rcu() if
there is preregistered XSK pool before subsequently call=20
__stmmac_disable_all_queues() to perform napi_disable().=20

After this, both stmmac_release() and stmmac_suspend() will use
stmmac_disable_all_queues().

Thx