Re: git: 1dfcff294e44 - main - release: increase IMAGE_SIZE for arm, arm64, riscv [odd alignment for SBC images]

On 2022-Jul-19, at 15:45, Warner Losh <imp@bsdimp.com> wrote:

> On Tue, Jul 19, 2022, 2:42 PM Glen Barber <gjb@freebsd.org> wrote:
>>> . . .
>> 
>> My concern with this is kern.geom.part.mbr.enforce_chs is always '1' on
>> the builders, which effectively means all arm builds will fail every
>> time.  I think we need to get to the actual root of the problem here,
>> versus applying band-aids to a shark bite.
> 
> I think this is the actual problem. While such pedantry can be useful for ancient picky BIOSes, these days only the LBA fields of the MBR are used. And the fake BIOS geometry is crazy weird. We can likely tweak it to be more friendly. 
> 
> Why is it == 1 on the builder? If people want things aligned gpart has an option for years iirc to do that. And we want that off for the builds.

Would it seem appropriate to use a week (this week?) to do all
the snapshot builds with the builders all set to have
kern.geom.part.mbr.enforce_chs=0 and see what breaks, if anything?
(Sort of a snapshot exp run.)

More than just the SBC images might be involved for
kern.geom.part.mbr.enforce_ch consequences, for all I know.

> Warner
> 
> P.s. the last BIOS that I had to deal with where this mattered was a 133MHz pentium PC104 board in 2002 or 2003.

===
Mark Millard
marklmi at yahoo.com