Re: Booting Kernel on Amiga 3000

[Michael Schmitz <schmitzmic@gmail.com>]

Hi Finn,

Am 09.09.2022 um 13:36 schrieb Finn Thain:

> > Kernel 5.19, intrd 5.19
> >
> > > > > > > > > > > > > > > > > > > > > >
> > [    0.000000] Linux version 5.19.0-1-m68k (debian-kernel@lists.debian.org) (gcc-11 (Debian 11.3.0-5) 11.3.0, GNU ld (GNU Binutils for Debian) 2.38.90.20220713) #1 Debian 5.19.6-1 (2022-09-01)
> > [    0.000000] printk: console [debug0] enabled
> > [    0.000000] Amiga hardware found: [A3000] VIDEO BLITTER AMBER_FF AUDIO FLOPPY A3000_SCSI KEYBOARD MOUSE SERIAL PARALLEL A3000_CLK CHIP_RAM PAULA DENISE_HR AGNUS_HR_PAL MAGIC_REKICK ZORRO3
> > [    0.000000] initrd: 0f7f6794 - 10000000
>
> Length is 0x80986d.
...
> > Kernel 5.18, intrid 5.18
> >
> > > > > > > > > > > > > > > > > > > > > >
> > [    0.000000] Linux version 5.18.0-3-m68k (debian-kernel@lists.debian.org) (gcc-11 (Debian 11.3.0-4) 11.3.0, GNU ld (GNU Binutils for Debian) 2.38.90.20220713) #1 Debian 5.18.14-1 (2022-07-23)
> > [    0.000000] printk: console [debug0] enabled
> > [    0.000000] Amiga hardware found: [A3000] VIDEO BLITTER AMBER_FF AUDIO FLOPPY A3000_SCSI KEYBOARD MOUSE SERIAL PARALLEL A3000_CLK CHIP_RAM PAULA DENISE_HR AGNUS_HR_PAL MAGIC_REKICK ZORRO3
> > [    0.000000] initrd: 0f7f7b16 - 10000000
>
> Length is 0x8084eb.
...
> > kernel 5.19, intrid 5.15
> >
> > > > > > > > > > > > > > > > > > > > > >
> > [    0.000000] Linux version 5.19.0-1-m68k (debian-kernel@lists.debian.org) (gcc-11 (Debian 11.3.0-5) 11.3.0, GNU ld (GNU Binutils for Debian) 2.38.90.20220713) #1 Debian 5.19.6-1 (2022-09-01)
> > [    0.000000] printk: console [debug0] enabled
> > [    0.000000] Amiga hardware found: [A3000] VIDEO BLITTER AMBER_FF AUDIO FLOPPY A3000_SCSI KEYBOARD MOUSE SERIAL PARALLEL A3000_CLK CHIP_RAM PAULA DENISE_HR AGNUS_HR_PAL MAGIC_REKICK ZORRO3
> > [    0.000000] initrd: 0f83283d - 10000000
>
> Length is 0x7cd7c4 which is below 8 MiB. Moreover, this is a known-good
> initrd. So the oops appears to be caused by a kernel change and not initrd
> growth.

All these have the initrd in the second memory chunk - at least one of 
the successful boots had the initrd in the first (8 MB) chunk).

I know nothing about the way amiboot works, and how the RAM chunk to 
copy the initrd image to is selected. Just speculating: maybe amiboot 
plus initrd size must be below 8 MB for the first chunk to get used?

But that's a little academic. I really wonder what makes the initrd at 
the end of the second RAM chunk fault. But e.g. the range

0f83283d - 10000000

extends one byte beyond what's mapped

node   0: [mem 0x0000000008000000-0x000000000fffffff]

and the fault occurs at faddr=0ffffff4, at which point the processor 
probably pre-fetched out to 10000000.

I need to dig out the 68040 manual to check what frame format 7 means...

Cheers,

	Michael