serial console on 8.x (probably sio vs uart)

Julian Elischer julian at
Fri Sep 12 17:04:57 UTC 2008

Marcel Moolenaar wrote:
> On Sep 11, 2008, at 11:13 PM, Julian Elischer wrote:
>> Peter Wemm wrote:
>>> On Thu, Sep 11, 2008 at 8:39 PM, Marcel Moolenaar <xcllnt at> 
>>> wrote:
>>>> On Sep 11, 2008, at 7:09 PM, Garance A Drosihn wrote:
>>>>> After I boot up, the only /dev/tty* devices I have are ttyv0
>>>>> through ttyvf.  I've installed the new /etc/ttys and a new
>>>>> /boot/device.hints, though frankly device.hints has always
>>>>> been a magic-box to me, so I just blindly copied what was in
>>>>> GENERIC.hints and changed hint.uart.0.flags to be "0x30".
>>>> uart(4) does tell you when it's the console:
>>>> uart0: <16550 or compatible> port 0x3f8-0x3ff irq 4 on acpi0
>>>> uart0: [FILTER]
>>>> uart0: console (115200,n,8,1)
>>>> The first question is: do you see a line like the one above?
>>>> If not (most likely), try to boot explicitly with a serial
>>>> console (i.e. set boot_serial=yes at the loader prompt or
>>>> boot with -h).
>>> He probably also needs to update his /boot/device.hints file.
>>> (change sio to uart)
>> I think uart should read  'sio' entries if there is no sio in the 
>> kernel, and it hasn't found any uart entries..
> No. Hints are optional and misused as they are. We're
> not making things any cleaner if we make driver X look
> for hints for driver Y.

yeah but I almost bricked a machine the other day upgrading because
I didn't have any uart hints but there were sio hints from the
previous kernel that would have done the job.

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