[Nachteule]

(28th Apr, 2018 01:00 AM)rafhtl Wrote:  I am testing now 4.9.96+ on rpi3 B+

it's working correctly

You're a lucky guy

Yes. I added a patch to lan78xx driver that makes things better. But there are still critical issues in this driver. In my environment. 4.14 works much better than 4.9 (and it is a bit faster) and is more usable if I communicate to another 1GBit machine. But, if I'm sending data to a 100MBit machine, nothing worked stable as usual

Kernel 4.14.37 is build with DYNAMIC_DEBUG option enabled. So you can enable driver debug messages as follows

Terminal

echo -n 'module lan78xx +p' > /sys/kernel/debug/dynamic_debug/control
ethtool -s eth0 msglvl 255

And when things going worse, you'll get messages like this in dmesg

Code:

[Fr Apr 27 17:13:17 2018] lan78xx 1-1.1.1:1.0 eth0: can not linearize skb
[Fr Apr 27 17:13:17 2018] lan78xx 1-1.1.1:1.0 eth0: can not linearize skb
[Fr Apr 27 17:13:17 2018] lan78xx 1-1.1.1:1.0 eth0: update stats

And the main issue is that driver can not linearize socket buffer very often (still having no idea why)
Socket has to be linearized because it is send as it is directly to lan controller

Here is the comment of the linearize function, and this makes me not really happy

Code:

/* Moves tail of skb head forward, copying data from fragmented part,
* when it is necessary.
* 1. It may fail due to malloc failure.
* 2. It may change skb pointers.
*
* It is pretty complicated. Luckily, it is called only in exceptional cases.
*/