Boot stucks at "Loading initial ramdisk"

[Dileep Sankhla]

Hi Aditya,

Yes, I also meant the same.

Thanks for the additional info though.

Regards,
Dileep

On Fri, Jan 5, 2024 at 1:33 PM Aditya Gupta <adityag at linux.ibm.com> wrote:
>
> Hi Dileep,
>
> On Mon, Jan 01, 2024 at 04:46:03PM +0530, Dileep Sankhla wrote:
> > >
> > > Thanks for your solution. Mine is fine in size and I am already using
> > > MODULES=dep.
> > >
> >
> > Sorry, my bad. I thought 18M was good enough but after asking this on
> > LinuxQuestions.org, I got to know that it was not sufficient for the boot
> > success (see [1]). Copying the existing kernel version's config from
> > `/boot` and running `make olddefconfig` solved the size issue for me. It is
> > now ~78M. The size of the kernel's initrd that I was using earlier is ~71M.
> >
>
> Just for the clarity, the size of initrd being only 18 MB is likely not
> the root cause for your system not booting, it would likely be that some
> modules were missing earlier.
>
> Likely why you built linux with a default config (defconfig), many
> modules might have been missing, which are required on your system to
> boot correctly. For example, file system support for btrfs will require
> the btrfs module, etc.
>
> Generally while creating initrd, `dracut` (on rhel/fedora), or
> `mkinitcpio`/`mkinitramfs` also copy your kernel's modules (at
> /lib/modules/new-kernel-version/*) to the initrd.
>
> Since you had less modules the first time you built with defconfig, so
> initrd also had less modules, and hence size was only 18MB.
>
> Later when you built using the distro kernel's config, you likely had
> many more modules, and hence more modules were put in the initrd also,
> causing it's size to increase, and since you used distro kernel config,
> so your modules would be similar in the kernel you built, and hence
> similar size of the initrd ~70MB.
>
> It's a good start to use the distro config for building a kernel.
>
> PS. I have been able to successfully boot by building with defconfig,
> then manually enabling some drivers according to error messages during
> boot, but that is for learning only, normally it might be a waste of
> time.
> And also I boot my ArchLinux with no initrd, and have had even smaller
> initrd and booted successfully, how I did that was building only the
> modules I knew my system needed as built-in.
>
> Regards,
> Aditya Gupta
>