Re: gptzfsboot grew a lot after skein support was added; need knob to control bloat

On 2017-01-28 14:04, Ngie Cooper wrote:
> On Sat, Jan 28, 2017 at 10:57 AM, Allan Jude <allanjude_at_freebsd.org> wrote:
>> On 2017-01-28 13:56, Ngie Cooper wrote:
>>> On Sat, Jan 28, 2017 at 8:56 AM, Warner Losh <imp_at_bsdimp.com> wrote:
>>>
>>> ...
>>>
>>>> So? It literally doesn't matter where the freebsd-boot partition
>>>> lives, or what it's number is. You can put it at the start or end of
>>>> the swap partition after adjusting its size. I've done this on several
>>>> systems...  NanoBSD plays games with this stuff as well to be bootable
>>>> on old / new systems.
>>>
>>> True. Hopefully my BIOS/disk controller isn't dumb enough to not
>>> support large disks properly.
>>>
>>> *sigh* Unfortunately, in my infinity cleverness I only put 2
>>> partitions on the drive -- freebsd-boot and freebsd-zfs. I guess I'll
>>> need to make backups of my workstation so I don't lose anything
>>> critical.
>>
>> Did gptzfsboot not fall below 64kb when you used the
>> LOADER_NO_GELI_SUPPORT knob?
> 
> It did, but unfortunately that's still way too small for my
> freebsd-boot partition (which apparently is only 44kB large :/..):
> 
> Before:
> 
> $ ls -l `make -V.OBJDIR`/gptzfsboot
> -rw-r--r--  1 ngie  wheel  111662 Jan 28 11:00
> /usr/obj/usr/src/sys/boot/i386/gptzfsboot/gptzfsboot
> 
> After:
> 
> $ ls -l `make -V.OBJDIR`/gptzfsboot
> -rw-r--r--  1 ngie  wheel  65371 Jan 28 11:05
> /usr/obj/usr/src/sys/boot/i386/gptzfsboot/gptzfsboot
> 
> Time to do some more tricks to pare down the bootloader size.
> 
> Sidenote to the folks who drive the release notes and upgrade
> instructions for FreeBSD 12.x -- it needs to be clearly explained that
> gptzfsboot has grown considerably in size and mitigation instructions
> should be provided for updating gptzfsboot -- in particular with folks
> who might be using freebsd-update, so don't have the luxury of the
> choice of bootloader build options when upgrading.
> 
> Thanks,
> -Ngie
> 
> $ gpart list da0
> Geom name: da0
> modified: false
> state: OK
> fwheads: 255
> fwsectors: 63
> last: 250069646
> first: 34
> entries: 128
> scheme: GPT
> Providers:
> 1. Name: da0p1
>    Mediasize: 45056 (44K)
>    Sectorsize: 512
>    Stripesize: 0
>    Stripeoffset: 20480
>    Mode: r0w0e0
>    rawuuid: 29a79300-48b1-11e4-97ff-fc4dd43f2de9
>    rawtype: 83bd6b9d-7f41-11dc-be0b-001560b84f0f
>    label: (null)
>    length: 45056
>    offset: 20480
>    type: freebsd-boot
>    index: 1
>    end: 127
>    start: 40
> 2. Name: da0p2
>    Mediasize: 128035593728 (119G)
>    Sectorsize: 512
>    Stripesize: 0
>    Stripeoffset: 65536
>    Mode: r1w1e1
>    rawuuid: 4416180d-48b1-11e4-97ff-fc4dd43f2de9
>    rawtype: 516e7cba-6ecf-11d6-8ff8-00022d09712b
>    label: (null)
>    length: 128035593728
>    offset: 65536
>    type: freebsd-zfs
>    index: 2
>    end: 250069646
>    start: 128
> Consumers:
> 1. Name: da0
>    Mediasize: 128035676160 (119G)
>    Sectorsize: 512
>    Mode: r1w1e2
> 

What created a partition that small?

Even the FreeBSD 9.3 or 10.3 ZFS boot loaders would struggle to fit in
that space:

9.3:
-r--r--r--  1 root  wheel  42083 Jul 30  2015 /boot/gptzfsboot

10.3:
-r--r--r--  1 root  wheel  42143 Mar 25  2016 /boot/gptzfsboot


-- 
Allan Jude