Re: [PATCH 1/2] net: ethernet: sxgbe: remove private tx queue lock

On Thu 2016-12-15 23:33:22, Lino Sanfilippo wrote:

On 15.12.2016 22:32, Lino Sanfilippo wrote:

quoted

Ah ok. Then maybe priv->hw->dma->stop_tx() does not do the job correctly (stop the
tx path properly) and the HW is still active on the tx path while the tx buffers are
freed. OTOH stmmac_release() also stops the phy before the tx (and rx) paths are stopped.
Did you try to stop the phy fist in stmmac_tx_err_work(), too?

Regards,
Lino

And this is the "sledgehammer" approach: Do a complete shutdown and restart
of the hardware in case of tx error (against net-next and only
compile tested).

Wow, thanks a lot. I'll try to get the driver back to the non-working
state, and try it.

I believe I have some idea what is wrong there. (Missing memory barriers).

+static void stmmac_tx_err_work(struct work_struct *work)
+{
+	struct stmmac_priv *priv = container_of(work, struct stmmac_priv,
+						tx_err_work);
+	/* restart netdev */
+	rtnl_lock();
+	stmmac_release(priv->dev);
+	stmmac_open(priv->dev);
+	rtnl_unlock();
+}

Won't this up/down the interface, in a way userspace can observe?

Best regards,
									Pavel
-- 
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