Re: Disabling framebuffer at boot time

[tlaronde%polynum.com@localhost]

Hello,

Le Thu, Aug 18, 2022 at 09:52:43AM +0000, RVP a écrit :
> On Thu, 18 Aug 2022, tlaronde%polynum.com@localhost wrote:
> 
> > In order to suppress one possible cause of the problem, I'd like to
> > suppress support for the framebuffer (the kernel booted at the moment
> > is the GENERIC amd64 one).
> > 
> > Do I need to compile a custom kernel suppressing the support of the
> > framebuffer or is there a configuration via /boot.cfg (it's a BIOS
> > boot, not UEFI) allowing this to be achieved?
> > 
> 
> If you think the DRMKMS driver is the cause, you can disable it (or
> any other drivers for that matter).
> 
> To disable the Intel DRMKMS, in /boot.cfg add:
> userconf=disable i915drmkms*

Thank you! But unfortunately, the answer seems to be that the hardware
is not supported.

I have disabled i915 in /boot.cfg (this a Xeon with Intel graphics).
I have verified that GRUB2 chainloads the second stage bootloader
of NetBSD and that, if there is a problem there, it defaults back
to Debian/Linux (by chainloading non existing boot blocks to verify
GRUB2 was not stucked in this case; and first verifying under qemu
that the normal procedure worked with a standard emulated machine).

But the NetBSD kernel does not even crash (since I use the "boot once"
feature, if it would, I would get back to Debian). I use a GENERIC
kernel, so DDB_ONPANIC is not set meaning that I will not be able to go
any further.

There are some comments in src/sys/arch/x86/pci/imcsmb/imc.c about
things depending on vendor-specific not available information about
Ivy bridge (this Xeon uses it).

So I will have to keep Debian on it (there are no BSD images offered for
this entry level baremetal server).

Thanks!
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
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