diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index 2eef7daa01..46ce479dc3 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -2274,6 +2274,11 @@ int kvm_has_intx_set_mask(void) return kvm_state->intx_set_mask; } +bool kvm_arm_supports_user_irq(void) +{ + return kvm_check_extension(kvm_state, KVM_CAP_ARM_USER_IRQ); +} + #ifdef KVM_CAP_SET_GUEST_DEBUG struct kvm_sw_breakpoint *kvm_find_sw_breakpoint(CPUState *cpu, target_ulong pc) diff --git a/accel/stubs/kvm-stub.c b/accel/stubs/kvm-stub.c index ef0c7346af..3965c528d3 100644 --- a/accel/stubs/kvm-stub.c +++ b/accel/stubs/kvm-stub.c @@ -155,4 +155,9 @@ void kvm_init_cpu_signals(CPUState *cpu) { abort(); } + +bool kvm_arm_supports_user_irq(void) +{ + return false; +} #endif diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c index b305d9032a..5a0e2a3c1a 100644 --- a/hw/intc/arm_gic.c +++ b/hw/intc/arm_gic.c @@ -25,6 +25,7 @@ #include "qom/cpu.h" #include "qemu/log.h" #include "trace.h" +#include "sysemu/kvm.h" /* #define DEBUG_GIC */ @@ -1412,6 +1413,12 @@ static void arm_gic_realize(DeviceState *dev, Error **errp) return; } + if (kvm_enabled() && !kvm_arm_supports_user_irq()) { + error_setg(errp, "KVM with user space irqchip only works when the " + "host kernel supports KVM_CAP_ARM_USER_IRQ"); + return; + } + /* This creates distributor and main CPU interface (s->cpuiomem[0]) */ gic_init_irqs_and_mmio(s, gic_set_irq, gic_ops); diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h index 052e11f621..91fc07ee9a 100644 --- a/include/sysemu/kvm.h +++ b/include/sysemu/kvm.h @@ -220,6 +220,17 @@ int kvm_init_vcpu(CPUState *cpu); int kvm_cpu_exec(CPUState *cpu); int kvm_destroy_vcpu(CPUState *cpu); +/** + * kvm_arm_supports_user_irq + * + * Not all KVM implementations support notifications for kernel generated + * interrupt events to user space. This function indicates whether the current + * KVM implementation does support them. + * + * Returns: true if KVM supports using kernel generated IRQs from user space + */ +bool kvm_arm_supports_user_irq(void); + #ifdef NEED_CPU_H #include "cpu.h" diff --git a/target/arm/cpu.h b/target/arm/cpu.h index 16a1e59615..102c58afac 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -706,6 +706,9 @@ struct ARMCPU { void *el_change_hook_opaque; int32_t node_id; /* NUMA node this CPU belongs to */ + + /* Used to synchronize KVM and QEMU in-kernel device levels */ + uint8_t device_irq_level; }; static inline ARMCPU *arm_env_get_cpu(CPUARMState *env) diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 45554682f2..7c17f0d629 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -174,6 +174,12 @@ int kvm_arch_init(MachineState *ms, KVMState *s) */ kvm_async_interrupts_allowed = true; + /* + * PSCI wakes up secondary cores, so we always need to + * have vCPUs waiting in kernel space + */ + kvm_halt_in_kernel_allowed = true; + cap_has_mp_state = kvm_check_extension(s, KVM_CAP_MP_STATE); type_register_static(&host_arm_cpu_type_info); @@ -528,6 +534,51 @@ void kvm_arch_pre_run(CPUState *cs, struct kvm_run *run) MemTxAttrs kvm_arch_post_run(CPUState *cs, struct kvm_run *run) { + ARMCPU *cpu; + uint32_t switched_level; + + if (kvm_irqchip_in_kernel()) { + /* + * We only need to sync timer states with user-space interrupt + * controllers, so return early and save cycles if we don't. + */ + return MEMTXATTRS_UNSPECIFIED; + } + + cpu = ARM_CPU(cs); + + /* Synchronize our shadowed in-kernel device irq lines with the kvm ones */ + if (run->s.regs.device_irq_level != cpu->device_irq_level) { + switched_level = cpu->device_irq_level ^ run->s.regs.device_irq_level; + + qemu_mutex_lock_iothread(); + + if (switched_level & KVM_ARM_DEV_EL1_VTIMER) { + qemu_set_irq(cpu->gt_timer_outputs[GTIMER_VIRT], + !!(run->s.regs.device_irq_level & + KVM_ARM_DEV_EL1_VTIMER)); + switched_level &= ~KVM_ARM_DEV_EL1_VTIMER; + } + + if (switched_level & KVM_ARM_DEV_EL1_PTIMER) { + qemu_set_irq(cpu->gt_timer_outputs[GTIMER_PHYS], + !!(run->s.regs.device_irq_level & + KVM_ARM_DEV_EL1_PTIMER)); + switched_level &= ~KVM_ARM_DEV_EL1_PTIMER; + } + + /* XXX PMU IRQ is missing */ + + if (switched_level) { + qemu_log_mask(LOG_UNIMP, "%s: unhandled in-kernel device IRQ %x\n", + __func__, switched_level); + } + + /* We also mark unknown levels as processed to not waste cycles */ + cpu->device_irq_level = run->s.regs.device_irq_level; + qemu_mutex_unlock_iothread(); + } + return MEMTXATTRS_UNSPECIFIED; }