From b3f15ec3d809ccf2e171ca4e272a220d3c1a3e05 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Mon, 10 Feb 2020 11:47:57 +0000 Subject: [PATCH] kvm: arm/arm64: Fold VHE entry/exit work into kvm_vcpu_run_vhe() With VHE, running a vCPU always requires the sequence: 1. kvm_arm_vhe_guest_enter(); 2. kvm_vcpu_run_vhe(); 3. kvm_arm_vhe_guest_exit() ... and as we invoke this from the shared arm/arm64 KVM code, 32-bit arm has to provide stubs for all three functions. To simplify the common code, and make it easier to make further modifications to the arm64-specific portions in the near future, let's fold kvm_arm_vhe_guest_enter() and kvm_arm_vhe_guest_exit() into kvm_vcpu_run_vhe(). The 32-bit stubs for kvm_arm_vhe_guest_enter() and kvm_arm_vhe_guest_exit() are removed, as they are no longer used. The 32-bit stub for kvm_vcpu_run_vhe() is left as-is. There should be no functional change as a result of this patch. Signed-off-by: Mark Rutland Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20200210114757.2889-1-mark.rutland@arm.com --- arch/arm/include/asm/kvm_host.h | 3 --- arch/arm64/include/asm/kvm_host.h | 32 ------------------------- arch/arm64/kvm/hyp/switch.c | 39 +++++++++++++++++++++++++++++-- virt/kvm/arm/arm.c | 2 -- 4 files changed, 37 insertions(+), 39 deletions(-) diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h index bd2233805d99..cbd26ae95e7e 100644 --- a/arch/arm/include/asm/kvm_host.h +++ b/arch/arm/include/asm/kvm_host.h @@ -394,9 +394,6 @@ static inline void kvm_arch_vcpu_put_fp(struct kvm_vcpu *vcpu) {} static inline void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) {} static inline void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) {} -static inline void kvm_arm_vhe_guest_enter(void) {} -static inline void kvm_arm_vhe_guest_exit(void) {} - #define KVM_BP_HARDEN_UNKNOWN -1 #define KVM_BP_HARDEN_WA_NEEDED 0 #define KVM_BP_HARDEN_NOT_REQUIRED 1 diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index f6a77ddab956..d740ec00ecd3 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -628,38 +628,6 @@ static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {} static inline void kvm_clr_pmu_events(u32 clr) {} #endif -static inline void kvm_arm_vhe_guest_enter(void) -{ - local_daif_mask(); - - /* - * Having IRQs masked via PMR when entering the guest means the GIC - * will not signal the CPU of interrupts of lower priority, and the - * only way to get out will be via guest exceptions. - * Naturally, we want to avoid this. - * - * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a - * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU. - */ - pmr_sync(); -} - -static inline void kvm_arm_vhe_guest_exit(void) -{ - /* - * local_daif_restore() takes care to properly restore PSTATE.DAIF - * and the GIC PMR if the host is using IRQ priorities. - */ - local_daif_restore(DAIF_PROCCTX_NOIRQ); - - /* - * When we exit from the guest we change a number of CPU configuration - * parameters, such as traps. Make sure these changes take effect - * before running the host or additional guests. - */ - isb(); -} - #define KVM_BP_HARDEN_UNKNOWN -1 #define KVM_BP_HARDEN_WA_NEEDED 0 #define KVM_BP_HARDEN_NOT_REQUIRED 1 diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 72fbbd86eb5e..457067706b75 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -617,7 +617,7 @@ static void __hyp_text __pmu_switch_to_host(struct kvm_cpu_context *host_ctxt) } /* Switch to the guest for VHE systems running in EL2 */ -int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) +static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) { struct kvm_cpu_context *host_ctxt; struct kvm_cpu_context *guest_ctxt; @@ -670,7 +670,42 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) return exit_code; } -NOKPROBE_SYMBOL(kvm_vcpu_run_vhe); +NOKPROBE_SYMBOL(__kvm_vcpu_run_vhe); + +int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) +{ + int ret; + + local_daif_mask(); + + /* + * Having IRQs masked via PMR when entering the guest means the GIC + * will not signal the CPU of interrupts of lower priority, and the + * only way to get out will be via guest exceptions. + * Naturally, we want to avoid this. + * + * local_daif_mask() already sets GIC_PRIO_PSR_I_SET, we just need a + * dsb to ensure the redistributor is forwards EL2 IRQs to the CPU. + */ + pmr_sync(); + + ret = __kvm_vcpu_run_vhe(vcpu); + + /* + * local_daif_restore() takes care to properly restore PSTATE.DAIF + * and the GIC PMR if the host is using IRQ priorities. + */ + local_daif_restore(DAIF_PROCCTX_NOIRQ); + + /* + * When we exit from the guest we change a number of CPU configuration + * parameters, such as traps. Make sure these changes take effect + * before running the host or additional guests. + */ + isb(); + + return ret; +} /* Switch to the guest for legacy non-VHE systems */ int __hyp_text __kvm_vcpu_run_nvhe(struct kvm_vcpu *vcpu) diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c index efda376ab3c5..560d6f258297 100644 --- a/virt/kvm/arm/arm.c +++ b/virt/kvm/arm/arm.c @@ -797,9 +797,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) guest_enter_irqoff(); if (has_vhe()) { - kvm_arm_vhe_guest_enter(); ret = kvm_vcpu_run_vhe(vcpu); - kvm_arm_vhe_guest_exit(); } else { ret = kvm_call_hyp_ret(__kvm_vcpu_run_nvhe, vcpu); }