[PATCH v4 24/43] KVM: arm64: Handle Realm PSCI requests
From: Steven Price <steven.price@arm.com>
Date: 2024-08-21 15:40:34
Also in:
kvm, kvmarm, linux-arm-kernel, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
The RMM needs to be informed of the target REC when a PSCI call is made with an MPIDR argument. Expose an ioctl to the userspace in case the PSCI is handled by it. Co-developed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Steven Price <steven.price@arm.com> --- arch/arm64/include/asm/kvm_rme.h | 3 +++ arch/arm64/kvm/arm.c | 25 +++++++++++++++++++++++++ arch/arm64/kvm/psci.c | 29 +++++++++++++++++++++++++++++ arch/arm64/kvm/rme.c | 15 +++++++++++++++ 4 files changed, 72 insertions(+)
diff --git a/arch/arm64/include/asm/kvm_rme.h b/arch/arm64/include/asm/kvm_rme.h
index c50854f44674..5492e60aa8de 100644
--- a/arch/arm64/include/asm/kvm_rme.h
+++ b/arch/arm64/include/asm/kvm_rme.h@@ -117,6 +117,9 @@ int realm_set_ipa_state(struct kvm_vcpu *vcpu, unsigned long addr, unsigned long end, unsigned long ripas, unsigned long *top_ipa); +int realm_psci_complete(struct kvm_vcpu *calling, + struct kvm_vcpu *target, + unsigned long status); #define RME_RTT_BLOCK_LEVEL 2 #define RME_RTT_MAX_LEVEL 3
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 3d21659ae5ad..c57ed4f41bbc 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c@@ -1756,6 +1756,22 @@ static int kvm_arm_vcpu_set_events(struct kvm_vcpu *vcpu, return __kvm_arm_vcpu_set_events(vcpu, events); } +static int kvm_arm_vcpu_rmm_psci_complete(struct kvm_vcpu *vcpu, + struct kvm_arm_rmm_psci_complete *arg) +{ + struct kvm_vcpu *target = kvm_mpidr_to_vcpu(vcpu->kvm, arg->target_mpidr); + + if (!target) + return -EINVAL; + + /* + * RMM v1.0 only supports PSCI_RET_SUCCESS or PSCI_RET_DENIED + * for the status. But, let us leave it to the RMM to filter + * for making this future proof. + */ + return realm_psci_complete(vcpu, target, arg->psci_status); +} + long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) {
@@ -1878,6 +1894,15 @@ long kvm_arch_vcpu_ioctl(struct file *filp, return kvm_arm_vcpu_finalize(vcpu, what); } + case KVM_ARM_VCPU_RMM_PSCI_COMPLETE: { + struct kvm_arm_rmm_psci_complete req; + + if (!kvm_is_realm(vcpu->kvm)) + return -EINVAL; + if (copy_from_user(&req, argp, sizeof(req))) + return -EFAULT; + return kvm_arm_vcpu_rmm_psci_complete(vcpu, &req); + } default: r = -EINVAL; }
diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c
index 1f69b667332b..f9abab5d50d7 100644
--- a/arch/arm64/kvm/psci.c
+++ b/arch/arm64/kvm/psci.c@@ -103,6 +103,12 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) reset_state->reset = true; kvm_make_request(KVM_REQ_VCPU_RESET, vcpu); + /* + * Make sure we issue PSCI_COMPLETE before the VCPU can be + * scheduled. + */ + if (vcpu_is_rec(vcpu)) + realm_psci_complete(source_vcpu, vcpu, PSCI_RET_SUCCESS); /* * Make sure the reset request is observed if the RUNNABLE mp_state is
@@ -115,6 +121,10 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) out_unlock: spin_unlock(&vcpu->arch.mp_state_lock); + if (vcpu_is_rec(vcpu) && ret != PSCI_RET_SUCCESS) + realm_psci_complete(source_vcpu, vcpu, + ret == PSCI_RET_ALREADY_ON ? + PSCI_RET_SUCCESS : PSCI_RET_DENIED); return ret; }
@@ -142,6 +152,25 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) /* Ignore other bits of target affinity */ target_affinity &= target_affinity_mask; + if (vcpu_is_rec(vcpu)) { + struct kvm_vcpu *target_vcpu; + + /* RMM supports only zero affinity level */ + if (lowest_affinity_level != 0) + return PSCI_RET_INVALID_PARAMS; + + target_vcpu = kvm_mpidr_to_vcpu(kvm, target_affinity); + if (!target_vcpu) + return PSCI_RET_INVALID_PARAMS; + + /* + * Provide the references of running and target RECs to the RMM + * so that the RMM can complete the PSCI request. + */ + realm_psci_complete(vcpu, target_vcpu, PSCI_RET_SUCCESS); + return PSCI_RET_SUCCESS; + } + /* * If one or more VCPU matching target affinity are running * then ON else OFF
diff --git a/arch/arm64/kvm/rme.c b/arch/arm64/kvm/rme.c
index 337b3dd1e00c..45d49d12a34c 100644
--- a/arch/arm64/kvm/rme.c
+++ b/arch/arm64/kvm/rme.c@@ -95,6 +95,21 @@ static void free_delegated_page(struct realm *realm, phys_addr_t phys) free_page((unsigned long)phys_to_virt(phys)); } +int realm_psci_complete(struct kvm_vcpu *calling, struct kvm_vcpu *target, + unsigned long status) +{ + int ret; + + ret = rmi_psci_complete(virt_to_phys(calling->arch.rec.rec_page), + virt_to_phys(target->arch.rec.rec_page), + status); + + if (ret) + return -EINVAL; + + return 0; +} + static int realm_rtt_create(struct realm *realm, unsigned long addr, int level,
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2.34.1