On Fri, 21 Jul 2000, Maarten de Boer wrote:
> On Thu, 20 Jul 2000, [EMAIL PROTECTED] wrote:
> > thanks! now i need to figure out about the running as root problem...
> 
> Some obvious things:
> 
> I understand your concern, but I think it's good that running 
> highest priority applications is restricted to root. 

Yes, because, most importantly, a SCHED_FIFO or SCHED_RR thread may
freeze the entire user space whenever it feels like it.

However, this can be fixed with a watchdog, either in kernel space,
or in a daemon. Of course, for this to be *safe*, one has to make
sure the watchdog cannot be disabled by any RT application.

> Besides, when you give the application proper permissions during 
> installation, the user is not required to become root to run the 
> application.

Yep, but...

> If you are really concerned about security, you can have your
> processing stuff running in a seperate application, and have
> your gui application running as normal user. (like jMax for
> example)

...if the application runs plugins (in particular, closed source
plugins), you're in trouble. Basically, Win9x + Internet Explorer
reinvented. (For those who luckily escaped it; web pages could make
it download and execute binary applets without the user even seeing
what's going on. And Win9x doesn't have any kernel level
security...)

This *HAS* to be fixed, and at kernel level AFAIK.

> But than ofcourse you loose the threading, and have
> to think of some communication between gui and processing.

What's the big deal? This is pretty much required anyway... (Shared
memory still works, of course, if you want a simple "shared structs"
kind of interface.)


//David


.- M u C o S --------------------------------. .- David Olofson ------.
|          A Free/Open Multimedia            | |     Audio Hacker     |
|      Plugin and Integration Standard       | |    Linux Advocate    |
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.- A u d i a l i t y ------------------------. |        Singer        |
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