Re: 15.0-RELEASE boot panic when if_iwm_load="YES"

On Sun, 30 Nov 2025, Adrian Chadd wrote:

Hi,

> The firmware loading migrated from "build all firmware as kernel
> modules' to 'support loading firmware as files'.
> However, that's resulted in a couple behavioural changes:
>
> * there's a known bug in the firmware loader where if it's invoked by
> a driver before / is available, the kernel panics.
> * .. and yes, since they're files now, but drivers have no way of
> waiting cleanly until the filesystems are available,
>  things go sideways.
>
> Just add this to /etc/rc.conf :
>
> kld_list="if_iwm"
>
> (if you have an existnig kld_list line in there, add if_iwm to it instead)

But why?  iwm(4) would be loaded by devmatch automatically given it has a
MODULE_PNP_INFO entry.  So this entry should not be needed either.

In theory *nothing* is needed to load the driver.

Only the wlan/ifconfig lines in rc.conf and wpa_supplicant.conf need to be
done.


> Then run "fwget" to fetch the latest firmware needed, and then reboot.

fwget has NO idea about iwm.  iwm firmware is still in src and not ports!


Note: if that firmware would have been present loader.conf does has compat
entry lines for iwm firmware, so even loading iwm from loader should have
worked without anyone noticiing.


Karlo, for the records and the help of others:

I assume you installed a pkgbase version of FreeBSD but did not install
the firmware-iwm package initially which comes out of pkgbase;  would that
be correct?

/bz

-- 
Bjoern A. Zeeb                                                     r15:7