[PATCH 2/3] base-files: failsafe: Start also CPU interface for DSA

[Rafał Miłecki]

On 21.06.2021 16:57, Rafał Miłecki wrote:
> On 19.06.2021 20:36, Hauke Mehrtens wrote:
>> On a DSA switch the ports have an upper device, the CPU device, e.g.
>> eth0. This device has to be in up state to bring up the lower devices
>> like lan1.
>>
>> Parse the link device from "ip link show" and bring it into up stated
>> before bringing up the actual interface.
>>
>> This is needed to make network in failsafe on systems with DSA work.
>>
>> Signed-off-by: Hauke Mehrtens <hauke at hauke-m.de>
> 
> Idea behind this patch sounds OK (screen scraping of "ip" maybe a bit less).
> 
> The problem is this patch *breaks* network on normal (non-failsafe)
> bcm4908 (DSA target) boot. I don't know why. In ifconfig interfaces look
> OK. In "brctl show" everything seems fine too.
> 
> I've to keep debugging that problem. Meanwhile I'll also try kernel
> patch.
> 
> This patch doesn't affect (break or fix) bcm53xx with swconfig.

I forgot to tell: it *does* fix failsafe on bcm4908 (DSA target). It
just breaks normal boot network.

I tested kernel commit 9d5ef190e561 ("net: dsa: automatically bring up
DSA master when opening user port") and it breaks by network on bcm4908
just the same. So maybe it's some kernel / b53 / bcm4908enet bug. I'll
keep debugging that.