Re: [PATCH net-next 4/6] bridge: a netlink notification should be sent when those attributes are changed by br_sysfs_br

On 03/16/2016 03:29 PM, Xin Long wrote:

On Wed, Mar 16, 2016 at 10:14 PM, Nikolay Aleksandrov
[off-list ref] wrote:

quoted

On 03/16/2016 02:34 PM, Xin Long wrote:

quoted

Now when we change the attributes of bridge or br_port by netlink,
a relevant netlink notification will be sent, but if we change them
by ioctl or sysfs, no notification will be sent.

We should ensure that whenever those attributes change internally or from
sysfs/ioctl, that a netlink notification is sent out to listeners.

Also, NetworkManager will use this in the future to listen for out-of-band
bridge master attribute updates and incorporate them into the runtime
configuration.

This patch is used for br_sysfs_br. and we also need to remove some
rtnl_trylock in old functions so that we can call it in a common one.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 net/bridge/br_sysfs_br.c | 17 ++++++++---------
 net/bridge/br_vlan.c     | 30 +++++-------------------------
 2 files changed, 13 insertions(+), 34 deletions(-)

What about the group_addr option ? Changing it will not generate a notification.

group_addr is not a string-to-long convert in sysfs. so it's hard to use
store_bridge_parm, that's why I didn't modify it.

in group_addr_store():
it also tries to hold rtnl_lock. maybe we can send rtnl msg there.
what do you think?

Sounds good.

when I cooked this patch, I was wondering why br_recalculate_fwd_mask
"Must be protected by RTNL."

vlan_enabled and vlan_proto are changed under rtnl, also this can race with
changing via netlink