Porting OpenBSD's sysctl hw.sensors framework to FreeBSD

[John Baldwin]

On Thursday 12 July 2007 03:00:08 am Alexander Leidinger wrote:
> Quoting John Baldwin <jhb at freebsd.org> (from Wed, 11 Jul 2007 
11:45:26 -0400):
> 
> > On Wednesday 11 July 2007 07:49:59 am Alexander Leidinger wrote:
> 
> >> On the other hand you don't want to allow an userland tool to directly
> >> mess around with the registers on your RAID or NIC to get some status...
> >
> > Err, that's how all the RAID utilities I've used work.  They send firmware
> > commands from userland and parse the replies in userland.  One exception 
I've
> 
> That's sad... they should provide this functionality in the driver  
> instead, it would allow to use access restrictions for some parts.

Not really, it avoids having to duplicate a lot of work in drivers that can be 
written once in a cross-platform userland utility.  Drivers aren't really the 
place to be monitoring raid status sending pages, e-mails, etc.  It's best to 
let userland invoke sendmail, not the kernel. :)

> > seen so far is that for software RAID the firmware you are talking to is 
the
> > driver, not firmware on the card, so you use ioctls directly rather than 
an
> > ioctl that sends a command to the firmware on the card.
> 
> But you have to run this tool as root, don't you? You don't want to  
> let a user run such a tool (and nowadays even desktops start to have  
> RAID, so whoever sits at the machine may be interested to see some  
> status on his desktop).

Whatever talks directly to the driver needs to run as root, yes, but you could 
always write a proxy app that receives requests from utilities running as 
non-root and does its own access restrictions.

-- 
John Baldwin