Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-05 Thread Mark Rutland
On Sun, Nov 04, 2018 at 11:25:00AM +, Marc Zyngier wrote: > diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c > index 22fbbdbece3c..d50f912d3f4a 100644 > --- a/arch/arm64/kvm/sys_regs.c > +++ b/arch/arm64/kvm/sys_regs.c > @@ -314,10 +314,15 @@ static bool trap_raz_wi(struct

Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-04 Thread Marc Zyngier
Hi Richard, On Sun, 04 Nov 2018 09:50:29 +, Richard Henderson wrote: > > On 11/3/18 12:32 PM, Marc Zyngier wrote: > > We actively hide the LORegion feature from the guest since > > cc33c4e20185a391766ed5e78e2acc97e17ba511 (in the 4.17 time frame), so > > you shouldn't be able to obtain

Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-04 Thread Richard Henderson
On 11/3/18 12:32 PM, Marc Zyngier wrote: > We actively hide the LORegion feature from the guest since > cc33c4e20185a391766ed5e78e2acc97e17ba511 (in the 4.17 time frame), so > you shouldn't be able to obtain these on a recent host. I don't think that patch is ideal. In particular, LOR is a

Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-03 Thread Marc Zyngier
On Sat, 3 Nov 2018 09:53:44 + Richard Henderson wrote: Hi Richard, > Although, while I have you, Christopher, is there a way to extract the Limited > Ordering Region registers without modifying guest state? Those are > multiplexed > with LORN_EL1. We actively hide the LORegion feature

Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-03 Thread Richard Henderson
On 11/2/18 7:35 PM, Christoffer Dall wrote: >> It looks like the kernel can handle reads of ID_ISAR0_EL1 >> through ID_ISAR5_EL1, but not ID_ISAR6_EL1, any of the >> MVFR*_EL1 or ID_AA64_ISAR* or ID_AA64PFR*. >> >> This is probably because the kernel is way too old to be >> interestingly

Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-02 Thread Christoffer Dall
On Fri, Nov 02, 2018 at 04:36:35PM +, Peter Maydell wrote: > On 2 November 2018 at 14:54, Richard Henderson > wrote: > > My previous patch set for replacing feature bits with id registers > > failed to consider that these id registers are beginning to control > > migration, and thus we must

Re: [Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-02 Thread Peter Maydell
On 2 November 2018 at 14:54, Richard Henderson wrote: > My previous patch set for replacing feature bits with id registers > failed to consider that these id registers are beginning to control > migration, and thus we must fill them in for KVM as well. > > Thus, we want to initialize these values

[Qemu-devel] [PATCH v2 0/5] target/arm: KVM vs ARMISARegisters

2018-11-02 Thread Richard Henderson
My previous patch set for replacing feature bits with id registers failed to consider that these id registers are beginning to control migration, and thus we must fill them in for KVM as well. Thus, we want to initialize these values within CPU from the host. Finally, re-send the T32EE