WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] Re: [RFC] [PATCH] sysfs support for Xen attributes

Greg KH wrote:

What exactly do the different ioctls do?  Do they have to be ioctls?
Can you use configfs or sysfs for most of the stuff there?
The canonical example is /proc/xen/privcmd which is our userspace hypercall interface. A hypercall is software interrupt with a number of parameters passed via registers. This has to come from ring 1 for security reasons (the kernel is running in ring 1).

We wish to make management hypercalls as the root user in userspace which means we have to go through the kernel. Currently, we do this by having /proc/xen/privcmd accept an ioctl() that takes a structure that describe the register arguments. The kernel interface allows us to control who in userspace can execute hypercalls.

It would perhaps be possible to use a read/write interface for hypercalls but ioctl() seems a little less awkward. Suggestions are certainly appreciated though.

Right now, I think a misc char device with an ioctl() interface seems like the most promising way to do this. This doesn't seem like the sort of think one would want to expose in sysfs...

Regards,

Anthony Liguori

thanks,

greg k-h
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/




_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>