On 14 October 2019 22:33:22 CEST, Richard Weinberger <richard.weinberger@xxxxxxxxx> wrote: >Hi! > >My userspace needs /sys/class/net/eth0/brport/group_fwd_mask, so I set >up udev rules >to wait for the sysfs file. >Without luck. >Also "udevadm monitor" does not show any event related to >/sys/class/net/eth0/brport when I assign eth0 to a bridge. > >First I thought that the bridge code just misses to emit some events >but >br_add_if() calls kobject_uevent() which is good. > >Greg gave me the hint that the bridge code might not use the kobject >model >correctly. > >Enabling kobjekt debugging shows that all events are dropped: >[ 36.904602] device eth0 entered promiscuous mode >[ 36.904786] kobject: 'brport' (0000000028a47e33): kobject_uevent_env >[ 36.904789] kobject: 'brport' (0000000028a47e33): >kobject_uevent_env: filter function caused the event to drop! > >If I understood Greg correctly this is because the bridge code uses >plain kobjects which >have a parent object. Therefore all events are dropped. > >Shouldn't brport be a kset just like net_device->queues_kset? Hi Richard, I'm currently traveling and will be out of reach until mid-next week when I'll be able to take a closer look, but one thing which comes to mind is that on any bridge/port option change there should also be a netlink notification which you could use. I'll look into this and will probably cook a fix, if anyone hasn't beaten me to it by then. :) Cheers, Nik
