I finally catch the real problem: I am using an 'optimized' zlib1g package. It has some bugs.
** Changed in: openssh (Ubuntu) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2077047 Title: riscv server: fail to login if compress is enabled by client To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/openssh/+bug/2077047/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs