On 02/03/2012 04:52 PM, Anthony Liguori wrote: > On 02/03/2012 12:07 PM, Eric Northup wrote: >> On Thu, Feb 2, 2012 at 8:09 AM, Avi Kivity<a...@redhat.com> wrote: >> [...] >>> >>> Moving to syscalls avoids these problems, but introduces new ones: >>> >>> - adding new syscalls is generally frowned upon, and kvm will need >>> several >>> - syscalls into modules are harder and rarer than into core kernel code >>> - will need to add a vcpu pointer to task_struct, and a kvm pointer to >>> mm_struct >> - Lost a good place to put access control (permissions on /dev/kvm) >> for which user-mode processes can use KVM. >> >> How would the ability to use sys_kvm_* be regulated? > > Why should it be regulated? > > It's not a finite or privileged resource.
You're exposing a large, complex kernel subsystem that does very low-level things with the hardware. It's a potential source of exploits (from bugs in KVM or in hardware). I can see people wanting to be selective with access because of that. And sometimes it is a finite resource. I don't know how x86 does it, but on at least some powerpc hardware we have a finite, relatively small number of hardware partition IDs. -Scott -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html