On Tue, Oct 15, 2019 at 09:38:22PM +0200, Heiner Kallweit wrote: > On 15.10.2019 00:12, Russell King - ARM Linux admin wrote: > > On Mon, Oct 14, 2019 at 10:20:15PM +0200, Heiner Kallweit wrote: > >> On 14.10.2019 21:51, Stefan Wahren wrote: > >>> [add more recipients] > >>> > >>> Am 14.10.19 um 21:25 schrieb Daniel Wagner: > >>>> Moving the phy_prepare_link() up in phy_connect_direct() ensures that > >>>> phydev->adjust_link is set when the phy_check_link_status() is called. > >>>> > >>>> diff --git a/drivers/net/phy/phy_device.c > >>>> b/drivers/net/phy/phy_device.c index 9d2bbb13293e..2a61812bcb0d 100644 > >>>> --- a/drivers/net/phy/phy_device.c +++ b/drivers/net/phy/phy_device.c > >>>> @@ -951,11 +951,12 @@ int phy_connect_direct(struct net_device *dev, > >>>> struct phy_device *phydev, if (!dev) return -EINVAL; > >>>> > >>>> + phy_prepare_link(phydev, handler); > >>>> + > >>>> rc = phy_attach_direct(dev, phydev, phydev->dev_flags, > >>>> interface); > >>>> if (rc) > >> > >> If phy_attach_direct() fails we may have to reset phydev->adjust_link to > >> NULL, > >> as we do in phy_disconnect(). Apart from that change looks good to me. > > > > Sorry, but it doesn't look good to me. > > > > I think there's a deeper question here - why is the phy state machine > > trying to call the link change function during attach? > After your comment I had a closer look at the lm78xx driver and few things > look suspicious: > > - lan78xx_phy_init() (incl. the call to phy_connect_direct()) is called > after register_netdev(). This may cause races.
That isn't a problem. We have lots of network device drivers that do this - in their open() function. > - The following is wrong, irq = 0 doesn't mean polling. > PHY_POLL is defined as -1. Also in case of irq = 0 phy_interrupt_is_valid() > returns true. > > /* if phyirq is not set, use polling mode in phylib */ > if (dev->domain_data.phyirq > 0) > phydev->irq = dev->domain_data.phyirq; > else > phydev->irq = 0; Also unlikely to be the cause of this problem. phy_connect_direct() is called with an adjust link function, which is set via phy_prepare_link() in phy_connect_direct(), before interrupts are even considered. So, the window for the bug is somewhere before the call to phy_prepare_link() in phy_connect_direct(), but after lan78xx_mdio_init(). > - Manually calling genphy_config_aneg() in lan78xx_phy_init() isn't > needed, however this should not cause our problem. Again, way after the point where phydev->adjust_link is non-NULL, so this can't be it. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line in suburbia: sync at 12.1Mbps down 622kbps up According to speedtest.net: 11.9Mbps down 500kbps up
