Re: [PATCH] wwan: core: Fix missing RTM_NEWLINK event
From: Loic Poulain <hidden>
Date: 2021-07-22 17:51:17
Also in:
stable
On Thu, 22 Jul 2021 at 19:42, Sergey Ryazanov [off-list ref] wrote:
On Thu, Jul 22, 2021 at 7:44 PM Loic Poulain [off-list ref] wrote:quoted
On Thu, 22 Jul 2021 at 18:14, Sergey Ryazanov [off-list ref] wrote:quoted
On Thu, Jul 22, 2021 at 6:39 PM Loic Poulain [off-list ref] wrote:quoted
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!
quoted hunk ↗ jump to hunk
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(structwwan_device *wwandev, goto unlock; } + rtnl_configure_link(dev, NULL); /* trigger the RTM_NEWLINK event */ +
Testing right now. Loic