From: Lucas Stach <l.st...@pengutronix.de> Sent: Wednesday, September 09, 2015 5:14 PM > To: Duan Fugang-B38611 > Cc: da...@davemloft.net; netdev@vger.kernel.org; > bhutchi...@solarflare.com > Subject: Re: [PATCH net-next 1/1] net: fec: add netif status check before > set mac address > > Am Mittwoch, den 09.09.2015, 10:42 +0800 schrieb Fugang Duan: > > There exist one issue by below case that case system hang: > > ifconfig eth0 down > > ifconfig eth0 hw ether 00:10:19:19:81:19 > > > > After eth0 down, all fec clocks are gated off. In the > > .fec_set_mac_address() function, it will set new MAC address to > registers, which causes system hang. > > > > So it needs to add netif status check to avoid registers access when > > clocks are gated off. Until eth0 up the new MAC address are wrote into > related registers. > > > > Signed-off-by: Fugang Duan <b38...@freescale.com> > > --- > > drivers/net/ethernet/freescale/fec_main.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/net/ethernet/freescale/fec_main.c > > b/drivers/net/ethernet/freescale/fec_main.c > > index 91925e3..cd09dbb 100644 > > --- a/drivers/net/ethernet/freescale/fec_main.c > > +++ b/drivers/net/ethernet/freescale/fec_main.c > > @@ -3029,6 +3029,9 @@ fec_set_mac_address(struct net_device *ndev, void > *p) > > memcpy(ndev->dev_addr, addr->sa_data, ndev->addr_len); > > } > > > > + if (!netif_running(ndev)) > > + return 0; > This deserves a comment in the code as to why it is needed and how it > still works. > > Regards, > Lucas > > +
Ok, I will add comment on here in next version. Thanks. > > writel(ndev->dev_addr[3] | (ndev->dev_addr[2] << 8) | > > (ndev->dev_addr[1] << 16) | (ndev->dev_addr[0] << 24), > > fep->hwp + FEC_ADDR_LOW); > > -- > Pengutronix e.K. | Lucas Stach | > Industrial Linux Solutions | http://www.pengutronix.de/ | N�����r��y����b�X��ǧv�^�){.n�+���z�^�)����w* jg��� �����ݢj/���z�ޖ��2�ޙ����&�)ߡ�a���� �G���h��j:+v���w��٥
