[sugar] [RFC] teach sugar to update oom_adj

[Marco Pesenti Gritti]

On Wed, 2007-02-21 at 14:58 +0530, Joshua N Pritikin wrote:
> On Tue, Feb 20, 2007 at 05:15:19PM +0100, Marco Pesenti Gritti wrote:
> > On Tue, 2007-02-20 at 21:28 +0530, Joshua N Pritikin wrote:
> > > On Mon, Feb 19, 2007 at 01:51:07PM +0100, Marco Pesenti Gritti wrote:
> > > > Is /proc/pid/oom_adj supposed to be user writable?
> > > 
> > > It needs capable(CAP_SYS_RESOURCE). Is OLPC going to employ SELinux or 
> > > somesuch for Bitfrost? If not then some kind of mini-server running as 
> > > root will be needed to traverse the security barrier.
> > 
> > We already have that (hardwaremanager on dev.laptop.org).
> 
> Can any process connect to hardwaremanager? If so, then oom_adj needs 
> to be somewhere else. A malicious process could set oom_adj such that 
> the next process to die is sugar. Only sugar should have access to set 
> oom_adj.
> 

Currently any process can connect, but only sugar really needs to. I
don't see problem with limiting access.

> > Though I think functionality which is generic and fit in HAL should just
> > go there (less code for us to maintain). I have no idea if oom_adj fits
> > in HAL.
> 
> Doesn't HAL just issue events and load kernel modules? I don't think 
> oom_adj belongs in HAL.

Well they added an interface to get the battery level for example.
That's why I'm confused about what belongs to HAL and what doesn't.

Marco