Message ID | 1476792760-60356-1-git-send-email-john@phrozen.org |
---|---|
State | Not Applicable, archived |
Delegated to: | David Miller |
Headers | show |
On Tue, Oct 18, 2016 at 02:12:40PM +0200, John Crispin wrote: > The shutdown code only stopped the PHYs but does not diconnect them > properly. This could lead to null pointer deref related kernel oopses > during reboot. Fix this by calling phy_disconnect() after the PHYs are > stopped. Humm, i don't follow this. The phy is disconnected in dsa_slave_destroy(). Why is that not sufficient? Also, after calling dsa_slave_close(), dsa_slave_open() can be called. But with your change, the phy has gone, so we are going to have trouble. Andrew > > Signed-off-by: John Crispin <john@phrozen.org> > --- > net/dsa/slave.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/net/dsa/slave.c b/net/dsa/slave.c > index 68714a5..725d9f7 100644 > --- a/net/dsa/slave.c > +++ b/net/dsa/slave.c > @@ -154,8 +154,10 @@ static int dsa_slave_close(struct net_device *dev) > struct net_device *master = p->parent->dst->master_netdev; > struct dsa_switch *ds = p->parent; > > - if (p->phy) > + if (p->phy) { > phy_stop(p->phy); > + phy_disconnect(p->phy); > + } > > dev_mc_unsync(master, dev); > dev_uc_unsync(master, dev); > -- > 1.7.10.4 >
On 18/10/2016 14:29, Andrew Lunn wrote: > On Tue, Oct 18, 2016 at 02:12:40PM +0200, John Crispin wrote: >> The shutdown code only stopped the PHYs but does not diconnect them >> properly. This could lead to null pointer deref related kernel oopses >> during reboot. Fix this by calling phy_disconnect() after the PHYs are >> stopped. > > Humm, i don't follow this. > > The phy is disconnected in dsa_slave_destroy(). Why is that not > sufficient? > > Also, after calling dsa_slave_close(), dsa_slave_open() can be > called. But with your change, the phy has gone, so we are going to > have trouble. > > Andrew > Hi Andrew i am testing on v4.4 which did not have a phy_disconnect() call. this seems to have been fixed by cda5c15b so please ignore this patch John >> >> Signed-off-by: John Crispin <john@phrozen.org> >> --- >> net/dsa/slave.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/net/dsa/slave.c b/net/dsa/slave.c >> index 68714a5..725d9f7 100644 >> --- a/net/dsa/slave.c >> +++ b/net/dsa/slave.c >> @@ -154,8 +154,10 @@ static int dsa_slave_close(struct net_device *dev) >> struct net_device *master = p->parent->dst->master_netdev; >> struct dsa_switch *ds = p->parent; >> >> - if (p->phy) >> + if (p->phy) { >> phy_stop(p->phy); >> + phy_disconnect(p->phy); >> + } >> >> dev_mc_unsync(master, dev); >> dev_uc_unsync(master, dev); >> -- >> 1.7.10.4 >>
> Hi Andrew > > i am testing on v4.4 which did not have a phy_disconnect() call. this > seems to have been fixed by cda5c15b so please ignore this patch Hi John All patches must be against net-next, or net if it is a fix. Anything else is wrong.... Andrew
On 18/10/2016 15:24, Andrew Lunn wrote: >> Hi Andrew >> >> i am testing on v4.4 which did not have a phy_disconnect() call. this >> seems to have been fixed by cda5c15b so please ignore this patch > > Hi John > > All patches must be against net-next, or net if it is a fix. Anything > else is wrong.... > > Andrew > Hi Andrew, i know. i was testing on v4.4 and then rebased the patch against net-next without noticing that a similar patch had already been merged. regardless, using the latest net-next tree, the oops is gone without adding any patches. John
diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 68714a5..725d9f7 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -154,8 +154,10 @@ static int dsa_slave_close(struct net_device *dev) struct net_device *master = p->parent->dst->master_netdev; struct dsa_switch *ds = p->parent; - if (p->phy) + if (p->phy) { phy_stop(p->phy); + phy_disconnect(p->phy); + } dev_mc_unsync(master, dev); dev_uc_unsync(master, dev);
The shutdown code only stopped the PHYs but does not diconnect them properly. This could lead to null pointer deref related kernel oopses during reboot. Fix this by calling phy_disconnect() after the PHYs are stopped. Signed-off-by: John Crispin <john@phrozen.org> --- net/dsa/slave.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)