In gicv4, direct vlpi may be forward to PE without using LR or ap_list. If ICH_HCR_EL2.En is 0 in guest, direct vlpi cannot be accepted by PE. It will take long time for direct vlpi to be forwarded in some cases. Direct vlpi has to wait for ICH_HCR_EL2.En=1 where some other interrupts using LR need to be forwarded, because in kvm_vgic_flush_hwstate, if ap_list is empty, it will return quickly not setting ICH_HCR_EL2.En. To fix this, set ICH_HCR_EL2.En to 1 before returning to guest when using GICv4.
Signed-off-by: Nianyao Tang <[email protected]> --- arch/arm64/include/asm/kvm_asm.h | 1 + virt/kvm/arm/hyp/vgic-v3-sr.c | 10 ++++++++++ virt/kvm/arm/vgic/vgic-v4.c | 8 ++++++++ 3 files changed, 19 insertions(+) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index f5b79e9..0581c4d 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -79,6 +79,7 @@ extern void __vgic_v3_init_lrs(void); extern u32 __kvm_get_mdcr_el2(void); +extern void __vgic_v3_write_hcr(u32 vmcr); /* Home-grown __this_cpu_{ptr,read} variants that always work at HYP */ #define __hyp_this_cpu_ptr(sym) \ diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c index 264d92d..12027af 100644 --- a/virt/kvm/arm/hyp/vgic-v3-sr.c +++ b/virt/kvm/arm/hyp/vgic-v3-sr.c @@ -434,6 +434,16 @@ void __hyp_text __vgic_v3_write_vmcr(u32 vmcr) write_gicreg(vmcr, ICH_VMCR_EL2); } +u64 __hyp_text __vgic_v3_read_hcr(void) +{ + return read_gicreg(ICH_HCR_EL2); +} + +void __hyp_text __vgic_v3_write_hcr(u32 vmcr) +{ + write_gicreg(vmcr, ICH_HCR_EL2); +} + #ifdef CONFIG_ARM64 static int __hyp_text __vgic_v3_bpr_min(void) diff --git a/virt/kvm/arm/vgic/vgic-v4.c b/virt/kvm/arm/vgic/vgic-v4.c index 1ed5f22..515171a 100644 --- a/virt/kvm/arm/vgic/vgic-v4.c +++ b/virt/kvm/arm/vgic/vgic-v4.c @@ -208,6 +208,8 @@ int vgic_v4_sync_hwstate(struct kvm_vcpu *vcpu) if (!vgic_supports_direct_msis(vcpu->kvm)) return 0; + __vgic_v3_write_hcr(vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr & ~ICH_HCR_EN); + return its_schedule_vpe(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe, false); } @@ -220,6 +222,12 @@ int vgic_v4_flush_hwstate(struct kvm_vcpu *vcpu) return 0; /* + * Enable ICH_HCR_EL.En so that guest can accpet and handle direct + * vlpi. + */ + __vgic_v3_write_hcr(vcpu->arch.vgic_cpu.vgic_v3.vgic_hcr); + + /* * Before making the VPE resident, make sure the redistributor * corresponding to our current CPU expects us here. See the * doc in drivers/irqchip/irq-gic-v4.c to understand how this -- 1.9.1
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