Wed, Aug 29, 2018 at 05:24:28PM CEST, step...@networkplumber.org wrote:
>On Wed, 29 Aug 2018 09:18:55 +0200
>Jiri Pirko <j...@resnulli.us> wrote:
>
>> Tue, Aug 28, 2018 at 10:58:11PM CEST, mar...@holtmann.org wrote:
>> >The name value from SET_NETDEV_DEVTYPE only ended up in the uevent sysfs
>> >file as DEVTYPE= information. To avoid any kind of race conditions
>> >between netlink messages and reading from sysfs, it is useful to add the
>> >same string as new IFLA_DEVTYPE attribute included in the RTM_NEWLINK
>> >messages.
>> >
>> >For network managing daemons that have to classify ARPHRD_ETHER network
>> >devices into different types (like Wireless LAN, Bluetooth etc.), this
>> >avoids the extra round trip to sysfs and parsing of the uevent file.
>> >
>> >Signed-off-by: Marcel Holtmann <mar...@holtmann.org>
>> >---
>> > include/uapi/linux/if_link.h | 2 ++
>> > net/core/rtnetlink.c | 12 ++++++++++++
>> > 2 files changed, 14 insertions(+)
>> >
>> >diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
>> >index 43391e2d1153..781294972bb4 100644
>> >--- a/include/uapi/linux/if_link.h
>> >+++ b/include/uapi/linux/if_link.h
>> >@@ -166,6 +166,8 @@ enum {
>> > IFLA_NEW_IFINDEX,
>> > IFLA_MIN_MTU,
>> > IFLA_MAX_MTU,
>> >+ IFLA_DEVTYPE, /* Name value from SET_NETDEV_DEVTYPE */
>>
>> This is not something netdev-related. dev->dev.type is struct device_type.
>> This is a generic "device" thing. Incorrect to expose over
>> netdev-specific API. Please use "device" API for this.
>
>There is no device API in netlink. The whole point of this patch is to
>do it in one message. It might be a performance optimization, but I can't
>see how it could be a race condition. Devices set type before registering.
I understand. My point is to avoid exposing generic "struct device"
values over rtnetlink. It mixes apples and oranges.
