Comment 9 for bug 1648561

That wasn't really what I meant. We *can't* avoid having the errors as they are coming from the kernel as a result of what os-prober does. The best you can do is not run os-prober if you know it's not necessary (setting GRUB_DISABLE_OS_PROBER=1 in /etc/default/grub does that).

As far as the "Operation not permitted" errors, I'm not sure yet, I will need to look in the kernel sources to see if there's a reason to emit that particular error if someone tries to write directly to a device while it's being attempted to be mounted.