KVM: introduce kvm_arch_intc_initialized and use it in irqfd (01c94e64) · Commits · 戴 / test

Introduce __KVM_HAVE_ARCH_INTC_INITIALIZED define and associated kvm_arch_intc_initialized function. This latter allows to test whether the virtual interrupt controller is initialized and ready to accept virtual IRQ injection. On some architectures, the virtual interrupt controller is dynamically instantiated, justifying that kind of check. The new function can now be used by irqfd to check whether the virtual interrupt controller is ready on KVM_IRQFD request. If not, KVM_IRQFD returns -EAGAIN. Signed-off-by:

Eric Auger <eric.auger@linaro.org> Acked-by:

Christoffer Dall <christoffer.dall@linaro.org> Reviewed-by:

Andre Przywara <andre.przywara@arm.com> Acked-by:

Marc Zyngier <marc.zyngier@arm.com> Signed-off-by:

Christoffer Dall <christoffer.dall@linaro.org>

include/linux/kvm_host.h

+14 −0

Original line number	Diff line number	Diff line
		@@ -700,6 +700,20 @@ static inline wait_queue_head_t kvm_arch_vcpu_wq(struct kvm_vcpu vcpu)
		#endif
		}

		#ifdef __KVM_HAVE_ARCH_INTC_INITIALIZED
		/*
		* returns true if the virtual interrupt controller is initialized and
		* ready to accept virtual IRQ. On some architectures the virtual interrupt
		* controller is dynamically instantiated and this is not always true.
		*/
		bool kvm_arch_intc_initialized(struct kvm *kvm);
		#else
		static inline bool kvm_arch_intc_initialized(struct kvm *kvm)
		{
		return true;
		}
		#endif

		int kvm_arch_init_vm(struct kvm *kvm, unsigned long type);
		void kvm_arch_destroy_vm(struct kvm *kvm);
		void kvm_arch_sync_events(struct kvm *kvm);

virt/kvm/eventfd.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -311,6 +311,9 @@ kvm_irqfd_assign(struct kvm kvm, struct kvm_irqfd args)
		unsigned int events;
		int idx;

		if (!kvm_arch_intc_initialized(kvm))
		return -EAGAIN;

		irqfd = kzalloc(sizeof(*irqfd), GFP_KERNEL);
		if (!irqfd)
		return -ENOMEM;

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