Soliciting opinions on an extension of the bootinfo structure

Andrew Duane aduane at
Mon Sep 12 12:47:37 UTC 2011

Since this has turned out to be a more contentious idea than I thought, and the upcoming FDT work will probably remove the need for it at all, I'm withdrawing the idea. Although our current code uses such a platform extension structure, we can make do with either metadata or environment variables for the time being.

Andrew Duane
Juniper Networks
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aduane at


-----Original Message-----
From: John Baldwin [mailto:jhb at] 
Sent: Friday, September 09, 2011 8:32 AM
To: freebsd-arch at
Cc: Peter Wemm; Peter Grehan; freebsd-hackers at; Andrew Duane
Subject: Re: Soliciting opinions on an extension of the bootinfo structure

On Thursday, September 08, 2011 6:48:19 pm Peter Wemm wrote:
> On Thu, Sep 8, 2011 at 3:25 PM, Peter Grehan <grehan at> wrote:
> >> I'm proposing an extension framework for the bootinfo structure used
> >> to pass information from the bootstrap/loader to the kernel. Although
> >> I'm only proposing this for the MIPS bootinfo, it's completely
> >> applicable to any of them.
> >>
> >> What I propose is adding an optional platform extension structure:
> >> bootinfo_pext, surrounded by #ifdef BOOTINFO_PEXT
> >
> >  Any reason not to put the vendor bits into another piece of loader 
> > ? That seems the extensible way to add additional info from the loader,
> > rather than extending bootinfo (as was the case pre-loader days).
> >
> > later,
> It sounds like they're not using loader, which is probably a
> reasonable thing for their environment.

That doesn't stop you from adding metadata to the kernel.  It is just an array 
of variable length blobs appended after 'end'.  Any boot loader can support
adding metadata.

John Baldwin

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