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Date:   Mon, 12 Apr 2021 14:19:16 -0700 (PDT)
Message-Id: <20210412.141916.1569200948681549246.davem@davemloft.net>
To:     boon.leong.ong@intel.com
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Subject: Re: [PATCH net-next 6/7] net: stmmac: Enable RX via AF_XDP
 zero-copy
From:   David Miller <davem@davemloft.net>
In-Reply-To: <20210412154130.20742-7-boon.leong.ong@intel.com>
References: <20210412154130.20742-1-boon.leong.ong@intel.com>
        <20210412154130.20742-7-boon.leong.ong@intel.com>
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+	/* synchronize_rcu() needed for pending XDP buffers to drain */
+	for (queue = 0; queue < rx_queues_cnt; queue++) {
+		rx_q = &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 path?

Thank you.