So I ran it under gdb and set a breakpoint to find how unmount_cb() is being called and traced the problem back up to unuse_data_iterate(). It calls gdu_utils_is_in_use_full(), which incorrectly identifies the mount point of the filesystem as "/". So it looks like either it is finding the wrong mount point for the filesystem and trying to unmount the root ( which you obviously can't do ), or unuse_data_iterate() is actually being called on the root filesystem instead of the one you are trying to resize. Unfortunately I can't tell which since almost all of the data this code is working with gdb tells me has an incomplete type.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-disk-utility in Ubuntu. https://bugs.launchpad.net/bugs/1789922 Title: Resize is broken Status in gnome-disk-utility package in Ubuntu: New Bug description: Try to resize an ext4 partition with the gnome disks utility. It throws an error saying it can't unmount the filesystem because it isn't mounted. This is on 18.04. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-disk-utility/+bug/1789922/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp

