Re: [PATCH RESEND 00/62] initrd: remove classic initrd support

Nicolas Schichan <[email protected]> Fri, 19 Sep 2025 17:24:48 +0200
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Message-ID <CAHNNwZAzecVcJXZmycX063-=p-M5jVkfStfgYVKJruOFo7y9zg@mail.gmail.com>
Hello,

> > When booting with root=/dev/ram0 in the kernel commandline,
> > handle_initrd() where the deprecation message resides is never called,
> > which is rather unfortunate (init/do_mounts_initrd.c):

> Yes, this is unfortunate.
>
> I personally still think that initrd should be removed.

Considering that the deprecation message didn't get displayed in some
configurations, maybe it's a bit early at the very least.

> I suggest using workaround I described in cover letter.

I'm not too keen on having an initramfs just to loop-mount
/sys/firmware/initrd, after all current kernels are able to handle the
use case just fine.

It looks like there is a lot of code calling into specific filesystems
so that the initrd code can guess the size of the file system before
copying into /dev/ram0, and I believe this is what causes the main
gripe against initrd today. What is wrong with just copying
/initrd.image using its actual size into /dev/ram0 instead of guessing
it with the help of filesystem specific code ?

> Also, for unknown reasons I didn't get your letter in my inbox.
> (Not even in spam folder.) I ocasionally found it on lore.kernel.org .

Sorry about that, When I used git-send-email yesterday to reply, the
SMTP server I used wasn't authenticated to google, so all gmail
recipients were dropped. Hopefully this work better today.

Regards,

-- 
Nicolas Schichan