A recent bug in systemd [1] triggered the following kernel warning: A link change request failed with some changes committed already. Interface eth1 may have been left with an inconsistent configuration, please check.
do_setlink() performs multiple configuration updates, and if any of them fails, do_setlink() has no way to revert the previous ones. It is also not easy to validate everything in advance and perform a non-failing update then. However, do_setlink() has some basic validation that can be extended at least this case. IMO, it's better to fail before doing any changes than to perform a partial configuration update. This RFC contains two patches that move some checks to the validation stage (inet6_validate_link_af() function). Only one of the patches (if any) should be applied. Patch 1 only checks the presence of at least one parameter, and patch 2 also moves the validation for addrgenmode that is currently part of inet6_set_link_af(). Of course, there are still many ways how do_setlink() can fail and perform a partial update, but IMO it's better to prevent at least some cases that we can. Please express your opinions on this fix: do we need it, do we want to validate as much as possible (patch 2) or only basic stuff like the presence of parameters (patch 1)? I'm looking forward to hearing the feedback. Thanks, Max [1]: https://github.com/systemd/systemd/issues/12504 -- 2.19.1
