problems setting userpriv when distfiles and/or build directory is automounted

[heini]

I'm using the kernel automounter to mount distfiles, build directory and portage tree/overlays under /gentoo when needed. When not mounted, mountpoints have permission 555 and are owned by root (automounter is started with --ghost option). When mounted, /gentoo/distfiles and /gentoo/build both have permissions 775 and are owned by group paludisbuild. However, paludis still complains that the directories are owned by group root and it cannot use userpriv. If I make sure the directories are mounted (by cd'ing into them in other shells), paludis uses userprivs as expected.

[ciaranm]

What condition does the automounter use to start the mount? Paludis runs a stat() on the directory to check permissions -- is a stat() not enough to trigger the mount?

[heini]

Replying to ciaranm:

What condition does the automounter use to start the mount? Paludis runs a stat() on the directory to check permissions -- is a stat() not enough to trigger the mount?

One must at least chdir into it or try to access a file/dir inside. See attached perl program. The output of this program is as followed when run with the directory unmounted:

# ./test.pl

UID: 0

GID: 0

UID: 0

GID: 460

[ciaranm]

Ok, I suggest you make yourself a hook. A hook in install_all_pre, fetch_all_pre and uninstall_all_pre that triggers the automounter for the relevant directories should be enough. I don't think there's any point doing this as standard for a weird side case like yours.