On Tue, Feb 02, 2016 at 09:46:05AM +0000, Marc Zyngier wrote: > On 01/02/16 13:54, Christoffer Dall wrote: > > On Mon, Jan 25, 2016 at 03:53:44PM +0000, Marc Zyngier wrote: > >> A handful of system registers are still shared between EL1 and EL2, > >> even while using VHE. These are tpidr*_el[01], actlr_el1, sp0, elr, > >> and spsr. > > > > So by shared registers you mean registers that do both have an EL0/1 > > version as well as an EL2 version, but where accesses aren't rewritten > > transparently? > > No, I mean that these registers do *not* have a separate banked version. > There is only a single set of registers, which have to be save/restored > the old way. huh, ARMv8 clearly specifies the existence of TPIDR_EL0, TPIDR_EL1, and TPIDR_EL2, for example. I cannot seem to find anywhere in the VHE spec that says that the TPIDR_EL2 goes away. I'm confused now. > > > > > also, by sp0 do you mean sp_el0, and by elr you mean elr_el1, and by > > spsr you mean spsr_el1 ? > > sp0 -> sp_el0 indeed. elr and spsr really are the guest PC and PSTATE, > so I should really reword this commit message, it is utterly confusing. > I guess I don't understand the definition of a 'shared' register given your comments here... Thanks, -Christoffer -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
