systemd-nspawn uses hard-coded location for resolv.conf

[mbiebl]

At https://github.com/systemd/systemd/blob/master/src/nspawn/nspawn.c#L1413 we hard-code the location for the system installed resolv.conf and check for /usr/lib/systemd/resolv.conf

For split-usr systems, resolv.conf is not installed at /usr though, but /lib/systemd/resolv.conf:
https://github.com/systemd/systemd/blob/master/src/resolve/meson.build#L140 (rootlibexecdir)

[mbiebl]

Seems it's hard-coded in a few other places as well:

tmpfiles.d/etc.conf.m4:L! /etc/resolv.conf - - - - ../usr/lib/systemd/resolv.conf
src/nspawn/nspawn.c:        if (access("/usr/lib/systemd/resolv.conf", F_OK) >= 0 &&
src/nspawn/nspawn.c:                r = mount_verbose(LOG_DEBUG, "/usr/lib/systemd/resolv.conf", resolved, NULL, MS_BIND, NULL);

[poettering]

hmm, where's resolved itself installed on such systems? if it's in /usr/lib, then i figure its resolv.conf should also be in /usr/lib, and we should change rootlibexecdir → libexecdir here...

[mbiebl]

@poettering resolved is installed to roolibexecdir:

https://github.com/systemd/systemd/blob/master/meson.build#L1420

        executable('systemd-resolved',
                   systemd_resolved_sources,
                   gcrypt_util_sources,
                   include_directories : includes,
                   link_with : [libshared],
                   dependencies : [threads,
                                   libgcrypt,
                                   libgpg_error,
                                   libm,
                                   libidn],
                   install_rpath : rootlibexecdir,

https://github.com/systemd/systemd/blob/master/src/resolve/meson.build#L139

        install_data('resolv.conf',
                     install_dir : rootlibexecdir)

[poettering]

hmm, ok. an i figure that's because networkd can run in early boot too... maybe we should leave it that way then.

Anyway, a patch that fixes the resolv.conf path for split-usr systems would be greatly appreciated.