VT-d Posted-Interrupts is an enhancement to CPU side Posted-Interrupt. With VT-d Posted-Interrupts enabled, external interrupts from direct-assigned devices can be delivered to guests without VMM intervention when guest is running in non-root mode.
You can find the VT-d Posted-Interrtups Spec. in the following URL: http://www.intel.com/content/www/us/en/intelligent-systems/intel-technology/vt-directed-io-spec.html v7: * Define two weak irq bypass callbacks: - kvm_arch_irq_bypass_start() - kvm_arch_irq_bypass_stop() * Remove the x86 dummy implementation of the above two functions. * Print some useful information instead of WARN_ON() when the irq bypass consumer unregistration fails. * Fix an issue when calling pi_pre_block and pi_post_block. v6: * Rebase on 4.2.0-rc6 * Rebase on https://lkml.org/lkml/2015/8/6/526 and http://www.gossamer-threads.com/lists/linux/kernel/2235623 * Make the add_consumer and del_consumer callbacks static * Remove pointless INIT_LIST_HEAD to 'vdev->ctx[vector].producer.node)' * Use dev_info instead of WARN_ON() when irq_bypass_register_producer fails * Remove optional dummy callbacks for irq producer v4: * For lowest-priority interrupt, only support single-CPU destination interrupts at the current stage, more common lowest priority support will be added later. * Accoring to Marcelo's suggestion, when vCPU is blocked, we handle the posted-interrupts in the HLT emulation path. * Some small changes (coding style, typo, add some code comments) v3: * Adjust the Posted-interrupts Descriptor updating logic when vCPU is preempted or blocked. * KVM_DEV_VFIO_DEVICE_POSTING_IRQ --> KVM_DEV_VFIO_DEVICE_POST_IRQ * __KVM_HAVE_ARCH_KVM_VFIO_POSTING --> __KVM_HAVE_ARCH_KVM_VFIO_POST * Add KVM_DEV_VFIO_DEVICE_UNPOST_IRQ attribute for VFIO irq, which can be used to change back to remapping mode. * Fix typo v2: * Use VFIO framework to enable this feature, the VFIO part of this series is base on Eric's patch "[PATCH v3 0/8] KVM-VFIO IRQ forward control" * Rebase this patchset on git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git, then revise some irq logic based on the new hierarchy irqdomain patches provided by Jiang Liu <jiang....@linux.intel.com> Feng Wu (17): KVM: Extend struct pi_desc for VT-d Posted-Interrupts KVM: Add some helper functions for Posted-Interrupts KVM: Define a new interface kvm_intr_is_single_vcpu() KVM: Get Posted-Interrupts descriptor address from 'struct kvm_vcpu' KVM: Add interfaces to control PI outside vmx KVM: Make struct kvm_irq_routing_table accessible KVM: make kvm_set_msi_irq() public vfio: Select IRQ_BYPASS_MANAGER for vfio PCI devices vfio: Register/unregister irq_bypass_producer KVM: x86: Update IRTE for posted-interrupts KVM: Define two weak arch callbacks for irq bypass manager KVM: Implement IRQ bypass consumer callbacks for x86 KVM: Add an arch specific hooks in 'struct kvm_kernel_irqfd' KVM: Update Posted-Interrupts Descriptor when vCPU is preempted KVM: Update Posted-Interrupts Descriptor when vCPU is blocked KVM: Warn if 'SN' is set during posting interrupts by software iommu/vt-d: Add a command line parameter for VT-d posted-interrupts Documentation/kernel-parameters.txt | 1 + arch/x86/include/asm/kvm_host.h | 20 +++ arch/x86/kvm/Kconfig | 1 + arch/x86/kvm/irq_comm.c | 28 +++- arch/x86/kvm/vmx.c | 288 +++++++++++++++++++++++++++++++++++- arch/x86/kvm/x86.c | 167 +++++++++++++++++++-- drivers/iommu/irq_remapping.c | 12 +- drivers/vfio/pci/Kconfig | 1 + drivers/vfio/pci/vfio_pci_intrs.c | 9 ++ drivers/vfio/pci/vfio_pci_private.h | 2 + include/linux/kvm_host.h | 28 ++++ include/linux/kvm_irqfd.h | 2 + virt/kvm/eventfd.c | 22 ++- virt/kvm/irqchip.c | 10 -- virt/kvm/kvm_main.c | 3 + 15 files changed, 565 insertions(+), 29 deletions(-) -- 2.1.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
