"pelzflorian (Florian Pelz)" skribis: > On Mon, May 13, 2019 at 03:54:11PM +0200, Ludovic Courtès wrote: >> Can you show the mount options of you root file system? >> >> mount | grep 'on / ' >> > > [f_pelz12@tux6 ~]$ mount | grep 'on / ' > rpool/data/subvol-161199-disk-0 on / type zfs (rw,noatime,xattr,posixacl) I suspect ZFS-on-Linux (right?) is doing something unusual here: mount(2) specifies the following reasons for EACCESS, and I don’t see anything that would apply: --8<---------------cut here---------------start------------->8--- EACCES A component of a path was not searchable. (See also path_resolution(7).) EACCES Mounting a read-only filesystem was attempted without giving the MS_RDONLY flag. The file system may be read-only for various reasons, including: it resides on a read-only optical disk; it is resides on a device with a physical switch that has been set to mark the device read- only; the filesystem implementation was compiled with read-only support; or errors were detected when initially mounting the filesystem, so that it was marked read-only and can't be remounted as read-write (until the errors are fixed). Some filesystems instead return the error EROFS on an attempt to mount a read-only filesystem. EACCES The block device source is located on a filesystem mounted with the MS_NODEV option. --8<---------------cut here---------------end--------------->8--- What do the following commands do on this system? --8<---------------cut here---------------start------------->8--- $ mkdir -p /tmp/test/lib $ unshare -mrf mount /lib /tmp/test/lib -o bind,readonly --8<---------------cut here---------------end--------------->8--- Thanks, Ludo’.