Hello, Benjamin. On Tue, Mar 03, 2020 at 03:40:38PM +0100, Benjamin Berg wrote: > I believe systemd tries to resolve to /dev/sda but that seems to fail > for me. So I think there is a bug in that code; I'll verify that and > submit a fix if so. > > Which device should actually be selected? Is it /dev/sda or the mapper > device that / is mounted from? Right now, the situation isn't great with dm. When pagecache writebacks go through dm, in some cases including dm-crypt, the cgroup ownership information is completely lost and all writes end up being issued as the root cgroup, so it breaks down when dm is in use. In the longer term, what we wanna do is controlling at physical devices (sda here) and then updating dm so that it can maintain and propagate the ownership correctly but we aren't there yet. Thanks. -- tejun
