| Message ID | 1626968964-17249-1-git-send-email-loic.poulain@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | wwan: core: Fix missing RTM_NEWLINK event | expand |
Hello Loic, On Thu, Jul 22, 2021 at 6:39 PM Loic Poulain <loic.poulain@linaro.org> wrote: > By default there is no rtnetlink event generated when registering a > netdev with rtnl_link_ops until its rtnl_link_state is switched to > initialized (RTNL_LINK_INITIALIZED). This causes issues with user > tools like NetworkManager which relies on such event to manage links. > > Fix that by setting link to initialized (via rtnl_configure_link). Shouldn't the __rtnl_newlink() function call rtnl_configure_link() just after the newlink() callback invocation? Or I missed something? -- Sergey
On Thu, 22 Jul 2021 at 18:14, Sergey Ryazanov <ryazanov.s.a@gmail.com> wrote: > > Hello Loic, > > On Thu, Jul 22, 2021 at 6:39 PM Loic Poulain <loic.poulain@linaro.org> wrote: > > By default there is no rtnetlink event generated when registering a > > netdev with rtnl_link_ops until its rtnl_link_state is switched to > > initialized (RTNL_LINK_INITIALIZED). This causes issues with user > > tools like NetworkManager which relies on such event to manage links. > > > > Fix that by setting link to initialized (via rtnl_configure_link). > > Shouldn't the __rtnl_newlink() function call rtnl_configure_link() > just after the newlink() callback invocation? Or I missed something? Ah right, but the first call of rtnl_configure_link() (uninitialized) does not cause RTM_NEWLINK event (cf __dev_notify_flags). It however seems to work for other link types (e,g, rmnet), so probably something to clarify here. Regards, Loic > > -- > Sergey
On Thu, Jul 22, 2021 at 7:44 PM Loic Poulain <loic.poulain@linaro.org> wrote: > On Thu, 22 Jul 2021 at 18:14, Sergey Ryazanov <ryazanov.s.a@gmail.com> wrote: >> On Thu, Jul 22, 2021 at 6:39 PM Loic Poulain <loic.poulain@linaro.org> wrote: >>> By default there is no rtnetlink event generated when registering a >>> netdev with rtnl_link_ops until its rtnl_link_state is switched to >>> initialized (RTNL_LINK_INITIALIZED). This causes issues with user >>> tools like NetworkManager which relies on such event to manage links. >>> >>> Fix that by setting link to initialized (via rtnl_configure_link). >> >> Shouldn't the __rtnl_newlink() function call rtnl_configure_link() >> just after the newlink() callback invocation? Or I missed something? > > Ah right, but the first call of rtnl_configure_link() (uninitialized) > does not cause RTM_NEWLINK event (cf __dev_notify_flags). It however > seems to work for other link types (e,g, rmnet), so probably something > to clarify here. Just check additional netdev creation with hwsim: # ip link add wwan0.3 parentdev wwan0 type wwan linkid 3 On the other console: # ip -d mon 6: wwan0.3: <POINTOPOINT,NOARP> mtu 1500 qdisc noop state DOWN group default link/none promiscuity 0 minmtu 68 maxmtu 65535 wwan numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 But I saw no notification at the moment of wwan_hwsim module loading. This happens since I missed the rtnl_configure_link() call in the wwan_create_default_link() after the default link successful creation :( So we need your fix at least in the default link creation routine to fix ca374290aaad ("wwan: core: support default netdev creation"). Something like this: diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c index 3e16c318e705..374aa2cc884c 100644 --- a/drivers/net/wwan/wwan_core.c +++ b/drivers/net/wwan/wwan_core.c @@ -984,6 +984,8 @@ static void wwan_create_default_link(struct wwan_device *wwandev, goto unlock; } + rtnl_configure_link(dev, NULL); /* trigger the RTM_NEWLINK event */ + unlock: rtnl_unlock(); -- Sergey
On Thu, 22 Jul 2021 at 19:42, Sergey Ryazanov <ryazanov.s.a@gmail.com> wrote: > > On Thu, Jul 22, 2021 at 7:44 PM Loic Poulain <loic.poulain@linaro.org> wrote: > > On Thu, 22 Jul 2021 at 18:14, Sergey Ryazanov <ryazanov.s.a@gmail.com> wrote: > >> On Thu, Jul 22, 2021 at 6:39 PM Loic Poulain <loic.poulain@linaro.org> wrote: > >>> By default there is no rtnetlink event generated when registering a > >>> netdev with rtnl_link_ops until its rtnl_link_state is switched to > >>> initialized (RTNL_LINK_INITIALIZED). This causes issues with user > >>> tools like NetworkManager which relies on such event to manage links. > >>> > >>> Fix that by setting link to initialized (via rtnl_configure_link). > >> > >> Shouldn't the __rtnl_newlink() function call rtnl_configure_link() > >> just after the newlink() callback invocation? Or I missed something? > > > > Ah right, but the first call of rtnl_configure_link() (uninitialized) > > does not cause RTM_NEWLINK event (cf __dev_notify_flags). It however > > seems to work for other link types (e,g, rmnet), so probably something > > to clarify here. > > Just check additional netdev creation with hwsim: > > # ip link add wwan0.3 parentdev wwan0 type wwan linkid 3 > > On the other console: > > # ip -d mon > 6: wwan0.3: <POINTOPOINT,NOARP> mtu 1500 qdisc noop state DOWN group default > link/none promiscuity 0 minmtu 68 maxmtu 65535 > wwan numtxqueues 1 numrxqueues 1 gso_max_size 65536 gso_max_segs 65535 > > But I saw no notification at the moment of wwan_hwsim module loading. > This happens since I missed the rtnl_configure_link() call in the > wwan_create_default_link() after the default link successful creation > :( Yep just realized that! > So we need your fix at least in the default link creation routine to > fix ca374290aaad ("wwan: core: support default netdev creation"). > Something like this: > > diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c > index 3e16c318e705..374aa2cc884c 100644 > --- a/drivers/net/wwan/wwan_core.c > +++ b/drivers/net/wwan/wwan_core.c > @@ -984,6 +984,8 @@ static void wwan_create_default_link(struct > wwan_device *wwandev, > goto unlock; > } > > + rtnl_configure_link(dev, NULL); /* trigger the RTM_NEWLINK event */ > + Testing right now. Loic
diff --git a/drivers/net/wwan/wwan_core.c b/drivers/net/wwan/wwan_core.c index 3e16c31..409caf4 100644 --- a/drivers/net/wwan/wwan_core.c +++ b/drivers/net/wwan/wwan_core.c @@ -866,6 +866,10 @@ static int wwan_rtnl_newlink(struct net *src_net, struct net_device *dev, else ret = register_netdevice(dev); + /* Link initialized, notify new link */ + if (!ret) + rtnl_configure_link(dev, NULL); + out: /* release the reference */ put_device(&wwandev->dev);
By default there is no rtnetlink event generated when registering a netdev with rtnl_link_ops until its rtnl_link_state is switched to initialized (RTNL_LINK_INITIALIZED). This causes issues with user tools like NetworkManager which relies on such event to manage links. Fix that by setting link to initialized (via rtnl_configure_link). Cc: stable@vger.kernel.org Fixes: 88b710532e53 ("wwan: add interface creation support") Signed-off-by: Loic Poulain <loic.poulain@linaro.org> --- drivers/net/wwan/wwan_core.c | 4 ++++ 1 file changed, 4 insertions(+) -- 2.7.4