On Mon, Jun 16, 2025 at 03:21:47AM +0800, Kang-Che Sung wrote: > On 15/06/2025 16:09, Alexey Gladkov wrote: > > On Sun, Jun 15, 2025 at 03:35:17PM +0100, Harald van Dijk wrote: > >> util-linux's version of switch_root does the same ramfs/tmpfs check that > >> busybox does, but reacts to it differently: rather than exiting with an > >> error for other file systems, it simply prints a warning and carries on > >> without removing any files. Would doing that instead in busybox too be > >> enough to work for your use case? > > > > Yes, it will absolutely be better than a fatal error. I'm using > > switch_root in initramfs and of course I'd like to clean up root, but this > > way at least I can use switch_root from busybox. > > I'm +1 for util-linux's approach. It's simple and addresses Alexey's > overlayfs problem without being destructive.
Yes, but that would leave the modified data at the upper level in my case. > Alexey has said that overlayfs won't touch the lower layer, and thus > in this case, deleting files from an overlayfs root might not free > memory that much as you would think. Here, it might be better to leave > the files alone and not 'rm -rf' them. Typically overlayfs is used to temporarily modify read-only images such as docker/podman. When the base image (lower layer) is left unchanged and all changes are written to tmpfs and lost. If you don't delete the data in switch_root, it will be a waste of memory since you are not supposed to go back to root. This is a big difference from rm -rf. -- Rgrds, legion _______________________________________________ busybox mailing list [email protected] https://lists.busybox.net/mailman/listinfo/busybox
