KVM: arm64: vgic-v3: Enable trapping of Group-0 system registers

In order to be able to trap Group-0 GICv3 system registers, we need to
set ICH_HCR_EL2.TALL0 begore entering the guest. This is conditionnaly
done after having restored the guest's state, and cleared on exit.

Tested-by: Alexander Graf <agraf@suse.de>
Acked-by: David Daney <david.daney@cavium.com>
Acked-by: Christoffer Dall <cdall@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <cdall@linaro.org>
This commit is contained in:
Marc Zyngier 2017-06-09 12:49:45 +01:00
parent eab0b2dc4f
commit abf55766f7
2 changed files with 5 additions and 1 deletions

View file

@ -417,6 +417,7 @@
#define ICH_HCR_EN (1 << 0)
#define ICH_HCR_UIE (1 << 1)
#define ICH_HCR_TALL0 (1 << 11)
#define ICH_HCR_TALL1 (1 << 12)
#define ICH_HCR_EOIcount_SHIFT 27
#define ICH_HCR_EOIcount_MASK (0x1f << ICH_HCR_EOIcount_SHIFT)

View file

@ -21,6 +21,7 @@
#include "vgic.h"
static bool group0_trap;
static bool group1_trap;
void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
@ -260,6 +261,8 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu)
/* Get the show on the road... */
vgic_v3->vgic_hcr = ICH_HCR_EN;
if (group0_trap)
vgic_v3->vgic_hcr |= ICH_HCR_TALL0;
if (group1_trap)
vgic_v3->vgic_hcr |= ICH_HCR_TALL1;
}
@ -492,7 +495,7 @@ int vgic_v3_probe(const struct gic_kvm_info *info)
if (kvm_vgic_global_state.vcpu_base == 0)
kvm_info("disabling GICv2 emulation\n");
if (group1_trap) {
if (group0_trap || group1_trap) {
kvm_info("GICv3 sysreg trapping enabled (reduced performance)\n");
static_branch_enable(&vgic_v3_cpuif_trap);
}