How to get /dev/smb* ?

Conrad J. Sabatier conrads at
Wed Nov 2 10:01:31 UTC 2011

On Wed, 02 Nov 2011 11:44:39 +0400
Антон Клесс <rc5hack at> wrote:

> >
> > mbmon is very old.  I've never gotten it to work on any machine I've
> > every tried it on.
> >
> > Does your boot time output show anything smb-related at all, such as
> > maybe "smbios0: <System Management BIOS> at ..."?  It's possible
> > that your machine simply has no support for this.
> >
> # dmesg -a |grep smb
> - returns nothing.

I just noticed, looking back at your previous mail, that you don't seem
to have a "device smbios" line in your kernel config.  Try adding that
and see if the smbios facility shows up at boot time.  I don't really
understand the inner workings of this particular feature.  On my box, I
so see an indication in the boot time messages:

smbios0: <System Management BIOS> at iomem 0xfcd20-0xfcd3e on
smbios0: Version: 2.5

Although no "smbios0" device actually shows up under /dev.  Perhaps
some more knowledgeable individual might enlighten us as to what
capabilities having this in your kernel config actually enables.

Also, just looking at the (x)mbmon port, the COMMENT line in the
Makefile states:

A X motherboard monitor for LM78/79, W8378x, AS99127F, VT82C686 and

So, this port appears to be useful only on a very specific range of

> Does it means that it is no way to read temperature sensors on
> motherboard?

Well, it depends.  :-)

I'm not at all familiar with your particular processor/motherboard, so I
can only offer some rather limited advice that may steer you in the
right direction for further exploration.  There are a number of devices
you can enable in your kernel config that may provide some of what
you're looking for.

Here, on my amd64 box, for instance, "device amdtemp", along with
"device cpuctl" and "device cpufreq" makes the following dev.cpu.*
sysctls available, which are one way to (manually) monitor your
system.  As you can see below, this provides information on CPU
temperature and frequency.

# sysctl dev.cpu
dev.cpu.0.%desc: ACPI CPU
dev.cpu.0.%driver: cpu
dev.cpu.0.%location: handle=\_PR_.P001
dev.cpu.0.%pnpinfo: _HID=none _UID=0
dev.cpu.0.%parent: acpi0
dev.cpu.0.temperature: 47.0C
dev.cpu.0.freq: 2200
dev.cpu.0.freq_levels: 2200/23500 1100/14280
dev.cpu.0.cx_supported: C1/0
dev.cpu.0.cx_lowest: C1
dev.cpu.0.cx_usage: 100.00% last 1931us
dev.cpu.1.%desc: ACPI CPU
dev.cpu.1.%driver: cpu
dev.cpu.1.%location: handle=\_PR_.P002
dev.cpu.1.%pnpinfo: _HID=none _UID=0
dev.cpu.1.%parent: acpi0
dev.cpu.1.temperature: 47.0C
dev.cpu.1.cx_supported: C1/0
dev.cpu.1.cx_lowest: C1
dev.cpu.1.cx_usage: 100.00% last 4658us
dev.cpu.2.%desc: ACPI CPU
dev.cpu.2.%driver: cpu
dev.cpu.2.%location: handle=\_PR_.P003
dev.cpu.2.%pnpinfo: _HID=none _UID=0
dev.cpu.2.%parent: acpi0
dev.cpu.2.temperature: 47.0C
dev.cpu.2.cx_supported: C1/0
dev.cpu.2.cx_lowest: C1
dev.cpu.2.cx_usage: 100.00% last 3551us
dev.cpu.3.%desc: ACPI CPU
dev.cpu.3.%driver: cpu
dev.cpu.3.%location: handle=\_PR_.P004
dev.cpu.3.%pnpinfo: _HID=none _UID=0
dev.cpu.3.%parent: acpi0
dev.cpu.3.temperature: 47.0C
dev.cpu.3.cx_supported: C1/0
dev.cpu.3.cx_lowest: C1
dev.cpu.3.cx_usage: 100.00% last 4943us

I've never really delved that deeply into any hardware monitoring
tools, to be honest.  You're kind of getting into an area where I am
admittedly no expert.  :-)   But I'd suggest looking very carefully at
both /sys/conf/NOTES and /sys/$ARCH/conf/NOTES (as well as the GENERIC
kernel config) for some possible clues.  Refer to the man pages for any
specific devices of potential interest to see exactly what they're
about, and possibly ask some more questions here as you start to narrow
down the items that my possibly be useful to you.

Seriously, people here don't mind questions being asked, if they're
even semi-intelligent ones.  We're a friendly bunch, for the most
part.  :-)

Perhaps someone may offer you some more useful information on how to
monitor and/or control other aspects of your specific hardware
configuration besides CPU temperature and frequency.

Hope this helps in some small way.  Good luck!  :-)

Conrad J. Sabatier
conrads at

More information about the freebsd-questions mailing list