[07/16] KVM: arm64: nv: Plumb handling of GICv3 EL2 accesses

Message ID	20241217151331.934077-8-maz@kernel.org (mailing list archive)
State	New
Headers	show Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EC84B1F76C4; Tue, 17 Dec 2024 15:14:05 +0000 (UTC) From: Marc Zyngier <maz@kernel.org> To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: Joey Gouly <joey.gouly@arm.com>, Suzuki K Poulose <suzuki.poulose@arm.com>, Oliver Upton <oliver.upton@linux.dev>, Zenghui Yu <yuzenghui@huawei.com>, Andre Przywara <andre.przywara@arm.com>, Eric Auger <eauger@redhat.com>, Ganapatrao Kulkarni <gankulkarni@os.amperecomputing.com> Subject: [PATCH 07/16] KVM: arm64: nv: Plumb handling of GICv3 EL2 accesses Date: Tue, 17 Dec 2024 15:13:22 +0000 Message-Id: <20241217151331.934077-8-maz@kernel.org> In-Reply-To: <20241217151331.934077-1-maz@kernel.org> References: <20241217151331.934077-1-maz@kernel.org> Precedence: bulk MIME-Version: 1.0 Content-Transfer-Encoding: 8bit
Series	KVM: arm64: Add NV GICv3 support \| expand [00/16] KVM: arm64: Add NV GICv3 support [01/16] arm64: sysreg: Add layout for ICH_HCR_EL2 [02/16] arm64: sysreg: Add layout for ICH_VTR_EL2 [03/16] arm64: sysreg: Add layout for ICH_MISR_EL2 [04/16] KVM: arm64: Move host SVE/SME state flags out of vCPU [05/16] KVM: arm64: nv: Load timer before the GIC [06/16] KVM: arm64: nv: Add ICH_*_EL2 registers to vpcu_sysreg [07/16] KVM: arm64: nv: Plumb handling of GICv3 EL2 accesses [08/16] KVM: arm64: nv: Sanitise ICH_HCR_EL2 accesses [09/16] KVM: arm64: nv: Nested GICv3 emulation [10/16] KVM: arm64: nv: Handle L2->L1 transition on interrupt injection [11/16] KVM: arm64: nv: Add Maintenance Interrupt emulation [12/16] KVM: arm64: nv: Respect virtual HCR_EL2.TWx setting [13/16] KVM: arm64: nv: Request vPE doorbell upon nested ERET to L2 [14/16] KVM: arm64: nv: Propagate used_lrs between L1 and L0 contexts [15/16] KVM: arm64: nv: Fold GICv3 host trapping requirements into guest setup [16/16] KVM: arm64: nv: Allow userland to set VGIC maintenance IRQ

diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 3cf7adb2b5038..209bc76263f10 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -23,7 +23,7 @@ kvm-y += arm.o mmu.o mmio.o psci.o hypercalls.o pvtime.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ vgic/vgic-mmio.o vgic/vgic-mmio-v2.o \ vgic/vgic-mmio-v3.o vgic/vgic-kvm-device.o \ - vgic/vgic-its.o vgic/vgic-debug.o + vgic/vgic-its.o vgic/vgic-debug.o vgic/vgic-v3-nested.o kvm-$(CONFIG_HW_PERF_EVENTS) += pmu-emul.o pmu.o kvm-$(CONFIG_ARM64_PTR_AUTH) += pauth.o diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 83c6b4a07ef56..c6d09c25b2522 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -17,6 +17,7 @@ #include <linux/mm.h> #include <linux/printk.h> #include <linux/uaccess.h> +#include <linux/irqchip/arm-gic-v3.h> #include <asm/arm_pmuv3.h> #include <asm/cacheflush.h> @@ -531,7 +532,13 @@ static bool access_gic_sre(struct kvm_vcpu *vcpu, if (p->is_write) return ignore_write(vcpu, p); - p->regval = vcpu->arch.vgic_cpu.vgic_v3.vgic_sre; + if (p->Op1 == 4) { /* ICC_SRE_EL2 */ + p->regval = (ICC_SRE_EL2_ENABLE | ICC_SRE_EL2_SRE | + ICC_SRE_EL1_DIB | ICC_SRE_EL1_DFB); + } else { /* ICC_SRE_EL1 */ + p->regval = vcpu->arch.vgic_cpu.vgic_v3.vgic_sre; + } + return true; } @@ -2402,6 +2409,59 @@ static bool access_zcr_el2(struct kvm_vcpu *vcpu, vq = SYS_FIELD_GET(ZCR_ELx, LEN, p->regval) + 1; vq = min(vq, vcpu_sve_max_vq(vcpu)); vcpu_write_sys_reg(vcpu, vq - 1, ZCR_EL2); + + return true; +} + +static bool access_gic_vtr(struct kvm_vcpu *vcpu, + struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + if (p->is_write) + return write_to_read_only(vcpu, p, r); + + p->regval = kvm_vgic_global_state.ich_vtr_el2; + p->regval &= ~(ICH_VTR_EL2_DVIM | + ICH_VTR_EL2_A3V | + ICH_VTR_EL2_IDbits); + p->regval |= ICH_VTR_EL2_nV4; + + return true; +} + +static bool access_gic_misr(struct kvm_vcpu *vcpu, + struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + if (p->is_write) + return write_to_read_only(vcpu, p, r); + + p->regval = vgic_v3_get_misr(vcpu); + + return true; +} + +static bool access_gic_eisr(struct kvm_vcpu *vcpu, + struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + if (p->is_write) + return write_to_read_only(vcpu, p, r); + + p->regval = vgic_v3_get_eisr(vcpu); + + return true; +} + +static bool access_gic_elrsr(struct kvm_vcpu *vcpu, + struct sys_reg_params *p, + const struct sys_reg_desc *r) +{ + if (p->is_write) + return write_to_read_only(vcpu, p, r); + + p->regval = vgic_v3_get_elrsr(vcpu); + return true; } @@ -3050,7 +3110,40 @@ static const struct sys_reg_desc sys_reg_descs[] = { EL2_REG(RVBAR_EL2, access_rw, reset_val, 0), { SYS_DESC(SYS_RMR_EL2), undef_access }, + EL2_REG_VNCR(ICH_AP0R0_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP0R1_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP0R2_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP0R3_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP1R0_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP1R1_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP1R2_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_AP1R3_EL2, reset_val, 0), + + { SYS_DESC(SYS_ICC_SRE_EL2), access_gic_sre }, + EL2_REG_VNCR(ICH_HCR_EL2, reset_val, 0), + { SYS_DESC(SYS_ICH_VTR_EL2), access_gic_vtr }, + { SYS_DESC(SYS_ICH_MISR_EL2), access_gic_misr }, + { SYS_DESC(SYS_ICH_EISR_EL2), access_gic_eisr }, + { SYS_DESC(SYS_ICH_ELRSR_EL2), access_gic_elrsr }, + EL2_REG_VNCR(ICH_VMCR_EL2, reset_val, 0), + + EL2_REG_VNCR(ICH_LR0_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR1_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR2_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR3_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR4_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR5_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR6_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR7_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR8_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR9_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR10_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR11_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR12_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR13_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR14_EL2, reset_val, 0), + EL2_REG_VNCR(ICH_LR15_EL2, reset_val, 0), EL2_REG(CONTEXTIDR_EL2, access_rw, reset_val, 0), EL2_REG(TPIDR_EL2, access_rw, reset_val, 0), diff --git a/arch/arm64/kvm/vgic/vgic-v3-nested.c b/arch/arm64/kvm/vgic/vgic-v3-nested.c new file mode 100644 index 0000000000000..48bfd2f556a36 --- /dev/null +++ b/arch/arm64/kvm/vgic/vgic-v3-nested.c @@ -0,0 +1,125 @@ +// SPDX-License-Identifier: GPL-2.0-only + +#include <linux/cpu.h> +#include <linux/kvm.h> +#include <linux/kvm_host.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/uaccess.h> + +#include <kvm/arm_vgic.h> + +#include <asm/kvm_arm.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_nested.h> + +#include "vgic.h" + +#define ICH_LRN(n) (ICH_LR0_EL2 + (n)) + +struct mi_state { + u16 eisr; + u16 elrsr; + bool pend; +}; + +/* + * Nesting GICv3 support + * + * System register emulation: + * + * We get two classes of registers: + * + * - those backed by memory (LRs, APRs, HCR, VMCR): L1 can freely access + * them, and L0 doesn't see a thing. + * + * - those that always trap (ELRSR, EISR, MISR): these are status registers + * that are built on the fly based on the in-memory state. + * + * Only L1 can access the ICH_*_EL2 registers. A non-NV L2 obviously cannot, + * and a NV L2 would either access the VNCR page provided by L1 (memory + * based registers), or see the access redirected to L1 (registers that + * trap) thanks to NV being set by L1. + */ + +static bool lr_triggers_eoi(u64 lr) +{ + return !(lr & (ICH_LR_STATE | ICH_LR_HW)) && (lr & ICH_LR_EOI); +} + +static void vgic_compute_mi_state(struct kvm_vcpu *vcpu, struct mi_state *mi_state) +{ + u16 eisr = 0, elrsr = 0; + bool pend = false; + + for (int i = 0; i < kvm_vgic_global_state.nr_lr; i++) { + u64 lr = __vcpu_sys_reg(vcpu, ICH_LRN(i)); + + if (lr_triggers_eoi(lr)) + eisr |= BIT(i); + if (!(lr & ICH_LR_STATE)) + elrsr |= BIT(i); + pend |= (lr & ICH_LR_PENDING_BIT); + } + + mi_state->eisr = eisr; + mi_state->elrsr = elrsr; + mi_state->pend = pend; +} + +u16 vgic_v3_get_eisr(struct kvm_vcpu *vcpu) +{ + struct mi_state mi_state; + + vgic_compute_mi_state(vcpu, &mi_state); + return mi_state.eisr; +} + +u16 vgic_v3_get_elrsr(struct kvm_vcpu *vcpu) +{ + struct mi_state mi_state; + + vgic_compute_mi_state(vcpu, &mi_state); + return mi_state.elrsr; +} + +u64 vgic_v3_get_misr(struct kvm_vcpu *vcpu) +{ + struct mi_state mi_state; + u64 reg = 0, hcr, vmcr; + + hcr = __vcpu_sys_reg(vcpu, ICH_HCR_EL2); + vmcr = __vcpu_sys_reg(vcpu, ICH_VMCR_EL2); + + vgic_compute_mi_state(vcpu, &mi_state); + + if (mi_state.eisr) + reg |= ICH_MISR_EL2_EOI; + + if (__vcpu_sys_reg(vcpu, ICH_HCR_EL2) & ICH_HCR_EL2_UIE) { + int used_lrs = kvm_vgic_global_state.nr_lr; + + used_lrs -= hweight16(mi_state.elrsr); + reg |= (used_lrs <= 1) ? ICH_MISR_EL2_U : 0; + } + + if ((hcr & ICH_HCR_EL2_LRENPIE) && FIELD_GET(ICH_HCR_EL2_EOIcount_MASK, hcr)) + reg |= ICH_MISR_EL2_LRENP; + + if ((hcr & ICH_HCR_EL2_NPIE) && !mi_state.pend) + reg |= ICH_MISR_EL2_NP; + + if ((hcr & ICH_HCR_EL2_VGrp0EIE) && (vmcr & ICH_VMCR_ENG0_MASK)) + reg |= ICH_MISR_EL2_VGrp0E; + + if ((hcr & ICH_HCR_EL2_VGrp0DIE) && !(vmcr & ICH_VMCR_ENG0_MASK)) + reg |= ICH_MISR_EL2_VGrp0D; + + if ((hcr & ICH_HCR_EL2_VGrp1EIE) && (vmcr & ICH_VMCR_ENG1_MASK)) + reg |= ICH_MISR_EL2_VGrp1E; + + if ((hcr & ICH_HCR_EL2_VGrp1DIE) && !(vmcr & ICH_VMCR_ENG1_MASK)) + reg |= ICH_MISR_EL2_VGrp1D; + + return reg; +} diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h index 3a8ccfda34d29..5017fcc71e604 100644 --- a/include/kvm/arm_vgic.h +++ b/include/kvm/arm_vgic.h @@ -389,6 +389,10 @@ int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu); void kvm_vgic_load(struct kvm_vcpu *vcpu); void kvm_vgic_put(struct kvm_vcpu *vcpu); +u16 vgic_v3_get_eisr(struct kvm_vcpu *vcpu); +u16 vgic_v3_get_elrsr(struct kvm_vcpu *vcpu); +u64 vgic_v3_get_misr(struct kvm_vcpu *vcpu); + #define irqchip_in_kernel(k) (!!((k)->arch.vgic.in_kernel)) #define vgic_initialized(k) ((k)->arch.vgic.initialized) #define vgic_ready(k) ((k)->arch.vgic.ready)

[07/16] KVM: arm64: nv: Plumb handling of GICv3 EL2 accesses

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