Pavel,

meanwhile I updated to the supported kernels. The strange thing is, in 
the kernel 5.2.21 in my distro (Manjaro) it works.

While it is not working with 5.3.7.

I checked the kernel sources of my distro and the patch is included 
there.

I've attached a pcap and the dmesg output when using my small demo tool.

Can you check if it is the same issue as before or something different?



$ uname -r
5.3.7-2-MANJARO

$ mount.cifs -V
mount.cifs version: 6.8

$ samba --version
Version 4.10.8

Thanks
Moritz