QEMU prepends pathnames to command lines of Multiboot kernels and modules, contrary to the specification

When QEMU is launched with the -kernel option to boot a Multiboot image, the command line passed in the -append option is additionally prefixed the pathname of the kernel image and a space. Likewise, module command lines passed in the -initrd option are passed with the module pathname and a space prepended. At the very least the former is contary to what is prescribed in the Multiboot specification, version 0.6.96[0], which says in §3.3:

> General-purpose boot loaders should allow user a complete control on command line independently of other factors like image name.

With respect to module command lines, the spec is less clear, but GNU GRUB2 (the de facto reference implementation) does not prepend pathnames to command lines of either. I haven't tested GRUB legacy, but I assume it exhibits the same behaviour. It would be strange if passing pathnames was in fact intended; bootloader pathnames are useless to the loaded kernel, which may potentially have a completely different view of the file system from the bootloader.

Also, given that a kernel pathname may contain spaces, skipping it in the command line cannot be done reliably, while loading a Multiboot module from a pathname that contains spaces is outright impossible.

Found in 4.2.0, but latest git master apparently behaves the same.

[0]: https://www.gnu.org/software/grub/manual/multiboot/multiboot.html



The QEMU project is currently moving its bug tracking to another system.
For this we need to know which bugs are still valid and which could be
closed already. Thus we are setting the bug state to "Incomplete" now.

If the bug has already been fixed in the latest upstream version of QEMU,
then please close this ticket as "Fix released".

If it is not fixed yet and you think that this bug report here is still
valid, then you have two options:

1) If you already have an account on gitlab.com, please open a new ticket
for this problem in our new tracker here:

    https://gitlab.com/qemu-project/qemu/-/issues

and then close this ticket here on Launchpad (or let it expire auto-
matically after 60 days). Please mention the URL of this bug ticket on
Launchpad in the new ticket on GitLab.

2) If you don't have an account on gitlab.com and don't intend to get
one, but still would like to keep this ticket opened, then please switch
the state back to "New" or "Confirmed" within the next 60 days (other-
wise it will get closed as "Expired"). We will then eventually migrate
the ticket automatically to the new system (but you won't be the reporter
of the bug in the new system and thus you won't get notified on changes
anymore).

Thank you and sorry for the inconvenience.



This is an automated cleanup. This bug report has been moved to QEMU's
new bug tracker on gitlab.com and thus gets marked as 'expired' now.
Please continue with the discussion here:

 https://gitlab.com/qemu-project/qemu/-/issues/425