On Thu, Jul 13, 2017 at 12:45:00AM -0700, Ram Pai wrote: > On Wed, Jul 12, 2017 at 01:28:25PM +1000, Balbir Singh wrote: > > On Wed, 5 Jul 2017 14:21:51 -0700 > > Ram Pai <linuxram@xxxxxxxxxx> wrote: > > > > > Initial plumbing to manage all the keys supported by the > > > hardware. > > > > > > Total 32 keys are supported on powerpc. However pkey 0,1 > > > and 31 are reserved. So effectively we have 29 pkeys. > > > > > > This patch keeps track of reserved keys, allocated keys > > > and keys that are currently free. > > > > It looks like this patch will only work in guest mode? > > Is that an assumption we've made? What happens if I use > > keys when running in hypervisor mode? > > It works in supervisor mode, as a guest aswell as a bare-metal > kernel. Whatever needs to be done in hypervisor mode > is already there in power-kvm. I realize i did not answer your question accurately... "What happens if I use keys when running in hypervisor mode?" Its not clear what happens. As far as I can tell the MMU does not check key violation when in hypervisor mode. So effectively I think, keys are ineffective when in hypervisor mode. RP
