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Date:   Sat, 5 Jun 2021 01:41:15 +0200
From:   Andrew Lunn <andrew@lunn.ch>
To:     Oleksij Rempel <o.rempel@pengutronix.de>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        Heiner Kallweit <hkallweit1@gmail.com>,
        Russell King <linux@armlinux.org.uk>, kernel@pengutronix.de,
        linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
        netdev@vger.kernel.org
Subject: Re: [PATCH net-next v1 7/7] usbnet: run unbind() before
 unregister_netdev()
Message-ID: <YLq6G9luZrXW5vry@lunn.ch>
References: <20210604134244.2467-1-o.rempel@pengutronix.de>
 <20210604134244.2467-8-o.rempel@pengutronix.de>
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On Fri, Jun 04, 2021 at 03:42:44PM +0200, Oleksij Rempel wrote:
> unbind() is the proper place to disconnect PHY, but it will fail if
> netdev is already unregistered.

O.K, this partially answers the question i was about to ask for the
previous patch.

void phy_start(struct phy_device *phydev)
{
	mutex_lock(&phydev->lock);

	if (phydev->state != PHY_READY && phydev->state != PHY_HALTED) {
		WARN(1, "called from state %s\n",
		     phy_state_to_str(phydev->state));
		goto out;
	}

By skipping phy_error(), phydev->state is not set to PHY_HALTED. So if
you try to start the phy again, without disconnecting it, it looks
like there could be a problem.

But with this patch, i assume the PHY will always be disconnected and
later reconnected when the device is replugged.

      Andrew