solved: pmbr: Boot loader too large

[Daniel Braniss]

> hi,
> this is the output from gpart show:
> =>       34  976773101  ada0  GPT  (465G)
>          34       2048     1  freebsd-boot  (1.0M)
>        2082    4194304     2  freebsd-ufs  [bootme]  (2.0G)
>     4196386   12582912     3  freebsd-swap  (6.0G)
>    16779298  959993837     4  freebsd-zfs  (457G)
> 
> =>       34  976773101  ada1  GPT  (465G)
>          34       2048     1  freebsd-boot  (1.0M)
>        2082    4194304     2  freebsd-ufs  (2.0G)
>     4196386   12582912     3  freebsd-swap  (6.0G)
>    16779298  959993837     4  freebsd-zfs  (457G)
> 
> I also did:
> 	gpart bootcode -b /boot/pmbr ada0
> 
> I'm trying to boot and get
>   Boot loader too large
> 
> not matter if I boot from disk or pxe.
> The pmbr is 512 bytes, so what causes it to overshoot? 
> I don't know x86 assembler (nor want to :-), but the comment says: 
> 	545k should be enough
> so what's going on?

never underestimate the human stupidity (mine in this case) nor of the boot.
pmbr will load the whole partition, which was 1M, instead of the size of
gptboot :-(

reducing the size of the slice/partition fixed the issue.