ukbd attachment and root mount

[Andriy Gapon]

on 12/11/2008 13:53 Nate Eldredge said the following:
> On Wed, 12 Nov 2008, Andriy Gapon wrote:
> 
>> on 05/11/2008 17:24 Andriy Gapon said the following:
> [...]
>>> I have a legacy-free system (no PS/2 ports, only USB) and I wanted to
>>> try a kernel without atkbd and psm (with ums, ukbd, kbdmux), but was
>>> bitten hard when I made a mistake and kernel could not find/mount root
>>> filesystem.
>>>
>>> So I stuck at mountroot prompt without a keyboard to enter anything.
>>> This was repeatable about 10 times after which I resorted to live cd.
>>>
>>> Since then I put back atkbdc into my kernel. I guess BIOS or USB
>>> hardware emulate AT or PS/2 keyboard, so the USB keyboard works before
>>> the driver attaches. I guess I need such emulation e.g. for loader or
>>> boot0 configuration. But I guess I don't have to have atkbd driver in
>>> kernel.
>>
>> This turned out not to be a complete solution as it seems that there are
>> some quirks about legacy USB here, sometimes keyboard stops working even
>> at loader prompt (this is described in a different thread).
>>
>> ukbd attachment still puzzles me a lot.
>> I look at some older dmesg, e.g. this 7.0-RELEASE one:
>> http://www.mavetju.org/mail/view_message.php?list=freebsd-usb&id=2709973
>> and see that ukbd attaches along with ums before mountroot.
>>
>> I look at newer dmesg and I see that ums attaches at about the same time
>> as before but ukbd consistently attaches after mountroot.
>> I wonder what might cause such behavior and how to fix it.
>> I definitely would like to see ukbd attach before mountroot, I can debug
>> this issue, but need some hints on where to start.
> 
> I haven't been following this thread, and I'm pretty sleepy right now,
> so sorry if this is irrelevant, but I had a somewhat similar problem
> that was fixed by adding
> 
> hint.atkbd.0.flags="0x1"
> 
> to /boot/device.hints .
> 

I can try this, but I think this wouldn't help for two reasons:
1. I already tried kernel without atkb at all
2. if ukbd driver is not attached then I don't see any way USB keyboard
would work in non-legacy way

Anyway I will try this, thank you.

-- 
Andriy Gapon