Adding Prakash B in cc too, sorry.
Vijaya, please let me know if I missed something in your original patch.
I tested GICv3 KVM save/restore with v4.11-rc4 and Prakash B use case
with 4.10 kernel.
Thanks
Eric
On 28/03/2017 15:58, Eric Auger wrote:
> KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS needs to be checked before
> attempting to read ICC_CTLR_EL1; otherwise kernel versions not
> exposing this kvm device group will be incompatible with qemu 2.9.
>
> Fixes: 07a5628 ("hw/intc/arm_gicv3_kvm: Reset GICv3 cpu interface registers")
> Signed-off-by: Eric Auger <eric.au...@redhat.com>
> Reported-by: Prakash B <bjsprakash.li...@gmail.com>
>
> ---
>
> I understand the ICC_CTLR_EL1 state only is used in the put() function
> which is used for migration
> ---
> hw/intc/arm_gicv3_kvm.c | 17 +++++++++++------
> 1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/hw/intc/arm_gicv3_kvm.c b/hw/intc/arm_gicv3_kvm.c
> index 81f0403..4c3a88e 100644
> --- a/hw/intc/arm_gicv3_kvm.c
> +++ b/hw/intc/arm_gicv3_kvm.c
> @@ -614,12 +614,6 @@ static void arm_gicv3_icc_reset(CPUARMState *env, const
> ARMCPRegInfo *ri)
> s = c->gic;
> cpu = ARM_CPU(c->cpu);
>
> - /* Initialize to actual HW supported configuration */
> - kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS,
> - KVM_VGIC_ATTR(ICC_CTLR_EL1, cpu->mp_affinity),
> - &c->icc_ctlr_el1[GICV3_NS], false);
> -
> - c->icc_ctlr_el1[GICV3_S] = c->icc_ctlr_el1[GICV3_NS];
> c->icc_pmr_el1 = 0;
> c->icc_bpr[GICV3_G0] = GIC_MIN_BPR;
> c->icc_bpr[GICV3_G1] = GIC_MIN_BPR;
> @@ -628,6 +622,17 @@ static void arm_gicv3_icc_reset(CPUARMState *env, const
> ARMCPRegInfo *ri)
> c->icc_sre_el1 = 0x7;
> memset(c->icc_apr, 0, sizeof(c->icc_apr));
> memset(c->icc_igrpen, 0, sizeof(c->icc_igrpen));
> +
> + if (!kvm_device_check_attr(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS,
> + KVM_VGIC_ATTR(ICC_CTLR_EL1,
> cpu->mp_affinity))) {
> + return;
> + }
> + /* Initialize to actual HW supported configuration */
> + kvm_device_access(s->dev_fd, KVM_DEV_ARM_VGIC_GRP_CPU_SYSREGS,
> + KVM_VGIC_ATTR(ICC_CTLR_EL1, cpu->mp_affinity),
> + &c->icc_ctlr_el1[GICV3_NS], false);
> +
> + c->icc_ctlr_el1[GICV3_S] = c->icc_ctlr_el1[GICV3_NS];
> }
>
> static void kvm_arm_gicv3_reset(DeviceState *dev)
>
