From mboxrd@z Thu Jan 1 00:00:00 1970 From: Auger Eric Subject: Re: [PATCH v2 07/11] KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs Date: Tue, 16 May 2017 14:39:18 +0200 Message-ID: References: <20170509085618.28311-1-cdall@linaro.org> <20170509085618.28311-8-cdall@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Marc Zyngier , kvm@vger.kernel.org To: Jean-Philippe Brucker , Christoffer Dall , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:55398 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750765AbdEPMjX (ORCPT ); Tue, 16 May 2017 08:39:23 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: Hi Jean, Christoffer, On 16/05/2017 13:23, Jean-Philippe Brucker wrote: > Hi, > > On 09/05/17 09:56, Christoffer Dall wrote: >> Instead of waiting with registering KVM iodevs until the first VCPU is >> run, we can actually create the iodevs when the redist base address is >> set. The only downside is that we must now also check if we need to do >> this for VCPUs which are created after creating the VGIC, because there >> is no enforced ordering between creating the VGIC (and setting its base >> addresses) and creating the VCPUs. > > This triggers a BUG(), when the order is VGIC init, then VCPU init (which > is what kvmtool does). > > Issuing KVM_CREATE_VCPU after VGIC intialization produces the following calls: > > kvm_vm_ioctl_create_vcpu > kvm_arch_vcpu_create > kvm_vcpu_init > kvm_arch_vcpu_init > kvm_vgic_vcpu_init > vgic_register_redist_iodev > kvm_vcpu_get_idx > ... no VCPU registered yet in kvm->vcpus :( > BUG(); in QEMU use case, kvm_vgic_vcpu_init/vgic_register_redist_iodev does nothing since KVM_VGIC_V3_ADDR_TYPE_REDIST was not called yet and vgic->vgic_redist_base is undefined. Thus we postpone the redist_iodev registration until the redist base address is set. In QEMU case KVM_VGIC_V3_ADDR_TYPE_REDIST is called when all the CPUs are initialized and we were lucky. > > ... would later register vcpu: > kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu > > My quick fix is to move kvm_vgic_vcpu_init into kvm_arch_vcpu_postcreate, > but it discards the return value of kvm_vgic_vcpu_init, so I don't know > how to do it properly. changing the proto of kvm_arch_vcpu_postcreate and moving the kvm_vgic_vcpu_init there could be an alternative. By the way kvm_arch_vcpu_postcreate calls kvm_vgic_early_init() which looks strange now that we do something clever before. Thoughts? Thanks Eric > > Thanks, > Jean > >> Signed-off-by: Christoffer Dall >> Reviewed-by: Eric Auger >> --- >> include/kvm/arm_vgic.h | 1 + >> virt/kvm/arm/arm.c | 2 +- >> virt/kvm/arm/vgic/vgic-init.c | 21 ++++++++++++++++++ >> virt/kvm/arm/vgic/vgic-kvm-device.c | 7 +++++- >> virt/kvm/arm/vgic/vgic-mmio-v3.c | 43 +++++++++++++++++++++++++++++++++++-- >> virt/kvm/arm/vgic/vgic-v3.c | 6 ------ >> virt/kvm/arm/vgic/vgic.h | 3 ++- >> 7 files changed, 72 insertions(+), 11 deletions(-) >> >> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h >> index fabcc64..4ff65ef 100644 >> --- a/include/kvm/arm_vgic.h >> +++ b/include/kvm/arm_vgic.h >> @@ -286,6 +286,7 @@ extern struct static_key_false vgic_v2_cpuif_trap; >> >> int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write); >> void kvm_vgic_early_init(struct kvm *kvm); >> +int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu); >> int kvm_vgic_create(struct kvm *kvm, u32 type); >> void kvm_vgic_destroy(struct kvm *kvm); >> void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu); >> diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c >> index 7941699..9f6f522a4b 100644 >> --- a/virt/kvm/arm/arm.c >> +++ b/virt/kvm/arm/arm.c >> @@ -335,7 +335,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) >> >> kvm_arm_reset_debug_ptr(vcpu); >> >> - return 0; >> + return kvm_vgic_vcpu_init(vcpu); >> } >> >> void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) >> diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c >> index 0ea64a1..962bb57 100644 >> --- a/virt/kvm/arm/vgic/vgic-init.c >> +++ b/virt/kvm/arm/vgic/vgic-init.c >> @@ -226,6 +226,27 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis) >> return 0; >> } >> >> +/** >> + * kvm_vgic_vcpu_init() - Register VCPU-specific KVM iodevs >> + * @vcpu: pointer to the VCPU being created and initialized >> + */ >> +int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) >> +{ >> + int ret = 0; >> + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; >> + >> + if (!irqchip_in_kernel(vcpu->kvm)) >> + return 0; >> + >> + /* >> + * If we are creating a VCPU with a GICv3 we must also register the >> + * KVM io device for the redistributor that belongs to this VCPU. >> + */ >> + if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) >> + ret = vgic_register_redist_iodev(vcpu); >> + return ret; >> +} >> + >> static void kvm_vgic_vcpu_enable(struct kvm_vcpu *vcpu) >> { >> if (kvm_vgic_global_state.type == VGIC_V2) >> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c >> index 69ccfd5..10ae6f3 100644 >> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c >> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c >> @@ -86,8 +86,13 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) >> break; >> case KVM_VGIC_V3_ADDR_TYPE_REDIST: >> r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3); >> + if (r) >> + break; >> + if (write) { >> + r = vgic_v3_set_redist_base(kvm, *addr); >> + goto out; >> + } >> addr_ptr = &vgic->vgic_redist_base; >> - alignment = SZ_64K; >> break; >> default: >> r = -ENODEV; >> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c >> index 168269b..99da1a2 100644 >> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c >> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c >> @@ -565,7 +565,7 @@ unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev) >> * >> * Return 0 on success, -ERRNO otherwise. >> */ >> -static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) >> +int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) >> { >> struct kvm *kvm = vcpu->kvm; >> struct vgic_dist *vgic = &kvm->arch.vgic; >> @@ -574,6 +574,18 @@ static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) >> gpa_t rd_base, sgi_base; >> int ret; >> >> + /* >> + * We may be creating VCPUs before having set the base address for the >> + * redistributor region, in which case we will come back to this >> + * function for all VCPUs when the base address is set. Just return >> + * without doing any work for now. >> + */ >> + if (IS_VGIC_ADDR_UNDEF(vgic->vgic_redist_base)) >> + return 0; >> + >> + if (!vgic_v3_check_base(kvm)) >> + return -EINVAL; >> + >> rd_base = vgic->vgic_redist_base + kvm_vcpu_get_idx(vcpu) * SZ_64K * 2; >> sgi_base = rd_base + SZ_64K; >> >> @@ -619,7 +631,7 @@ static void vgic_unregister_redist_iodev(struct kvm_vcpu *vcpu) >> kvm_io_bus_unregister_dev(vcpu->kvm, KVM_MMIO_BUS, &sgi_dev->dev); >> } >> >> -int vgic_register_redist_iodevs(struct kvm *kvm) >> +static int vgic_register_all_redist_iodevs(struct kvm *kvm) >> { >> struct kvm_vcpu *vcpu; >> int c, ret = 0; >> @@ -641,6 +653,33 @@ int vgic_register_redist_iodevs(struct kvm *kvm) >> return ret; >> } >> >> +int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr) >> +{ >> + struct vgic_dist *vgic = &kvm->arch.vgic; >> + int ret; >> + >> + /* vgic_check_ioaddr makes sure we don't do this twice */ >> + ret = vgic_check_ioaddr(kvm, &vgic->vgic_redist_base, addr, SZ_64K); >> + if (ret) >> + return ret; >> + >> + vgic->vgic_redist_base = addr; >> + if (!vgic_v3_check_base(kvm)) { >> + vgic->vgic_redist_base = VGIC_ADDR_UNDEF; >> + return -EINVAL; >> + } >> + >> + /* >> + * Register iodevs for each existing VCPU. Adding more VCPUs >> + * afterwards will register the iodevs when needed. >> + */ >> + ret = vgic_register_all_redist_iodevs(kvm); >> + if (ret) >> + return ret; >> + >> + return 0; >> +} >> + >> int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr) >> { >> const struct vgic_register_region *region; >> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c >> index 2d53d7a..bb35078 100644 >> --- a/virt/kvm/arm/vgic/vgic-v3.c >> +++ b/virt/kvm/arm/vgic/vgic-v3.c >> @@ -397,12 +397,6 @@ int vgic_v3_map_resources(struct kvm *kvm) >> goto out; >> } >> >> - ret = vgic_register_redist_iodevs(kvm); >> - if (ret) { >> - kvm_err("Unable to register VGICv3 redist MMIO regions\n"); >> - goto out; >> - } >> - >> if (vgic_has_its(kvm)) { >> ret = vgic_register_its_iodevs(kvm); >> if (ret) { >> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h >> index 89eb935..5f17eac 100644 >> --- a/virt/kvm/arm/vgic/vgic.h >> +++ b/virt/kvm/arm/vgic/vgic.h >> @@ -174,7 +174,8 @@ int vgic_v3_probe(const struct gic_kvm_info *info); >> int vgic_v3_map_resources(struct kvm *kvm); >> int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq); >> int vgic_v3_save_pending_tables(struct kvm *kvm); >> -int vgic_register_redist_iodevs(struct kvm *kvm); >> +int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr); >> +int vgic_register_redist_iodev(struct kvm_vcpu *vcpu); >> bool vgic_v3_check_base(struct kvm *kvm); >> >> void vgic_v3_load(struct kvm_vcpu *vcpu); >> > > _______________________________________________ > kvmarm mailing list > kvmarm@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm > From mboxrd@z Thu Jan 1 00:00:00 1970 From: eric.auger@redhat.com (Auger Eric) Date: Tue, 16 May 2017 14:39:18 +0200 Subject: [PATCH v2 07/11] KVM: arm/arm64: Register iodevs when setting redist base and creating VCPUs In-Reply-To: References: <20170509085618.28311-1-cdall@linaro.org> <20170509085618.28311-8-cdall@linaro.org> Message-ID: To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Jean, Christoffer, On 16/05/2017 13:23, Jean-Philippe Brucker wrote: > Hi, > > On 09/05/17 09:56, Christoffer Dall wrote: >> Instead of waiting with registering KVM iodevs until the first VCPU is >> run, we can actually create the iodevs when the redist base address is >> set. The only downside is that we must now also check if we need to do >> this for VCPUs which are created after creating the VGIC, because there >> is no enforced ordering between creating the VGIC (and setting its base >> addresses) and creating the VCPUs. > > This triggers a BUG(), when the order is VGIC init, then VCPU init (which > is what kvmtool does). > > Issuing KVM_CREATE_VCPU after VGIC intialization produces the following calls: > > kvm_vm_ioctl_create_vcpu > kvm_arch_vcpu_create > kvm_vcpu_init > kvm_arch_vcpu_init > kvm_vgic_vcpu_init > vgic_register_redist_iodev > kvm_vcpu_get_idx > ... no VCPU registered yet in kvm->vcpus :( > BUG(); in QEMU use case, kvm_vgic_vcpu_init/vgic_register_redist_iodev does nothing since KVM_VGIC_V3_ADDR_TYPE_REDIST was not called yet and vgic->vgic_redist_base is undefined. Thus we postpone the redist_iodev registration until the redist base address is set. In QEMU case KVM_VGIC_V3_ADDR_TYPE_REDIST is called when all the CPUs are initialized and we were lucky. > > ... would later register vcpu: > kvm->vcpus[atomic_read(&kvm->online_vcpus)] = vcpu > > My quick fix is to move kvm_vgic_vcpu_init into kvm_arch_vcpu_postcreate, > but it discards the return value of kvm_vgic_vcpu_init, so I don't know > how to do it properly. changing the proto of kvm_arch_vcpu_postcreate and moving the kvm_vgic_vcpu_init there could be an alternative. By the way kvm_arch_vcpu_postcreate calls kvm_vgic_early_init() which looks strange now that we do something clever before. Thoughts? Thanks Eric > > Thanks, > Jean > >> Signed-off-by: Christoffer Dall >> Reviewed-by: Eric Auger >> --- >> include/kvm/arm_vgic.h | 1 + >> virt/kvm/arm/arm.c | 2 +- >> virt/kvm/arm/vgic/vgic-init.c | 21 ++++++++++++++++++ >> virt/kvm/arm/vgic/vgic-kvm-device.c | 7 +++++- >> virt/kvm/arm/vgic/vgic-mmio-v3.c | 43 +++++++++++++++++++++++++++++++++++-- >> virt/kvm/arm/vgic/vgic-v3.c | 6 ------ >> virt/kvm/arm/vgic/vgic.h | 3 ++- >> 7 files changed, 72 insertions(+), 11 deletions(-) >> >> diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h >> index fabcc64..4ff65ef 100644 >> --- a/include/kvm/arm_vgic.h >> +++ b/include/kvm/arm_vgic.h >> @@ -286,6 +286,7 @@ extern struct static_key_false vgic_v2_cpuif_trap; >> >> int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write); >> void kvm_vgic_early_init(struct kvm *kvm); >> +int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu); >> int kvm_vgic_create(struct kvm *kvm, u32 type); >> void kvm_vgic_destroy(struct kvm *kvm); >> void kvm_vgic_vcpu_early_init(struct kvm_vcpu *vcpu); >> diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c >> index 7941699..9f6f522a4b 100644 >> --- a/virt/kvm/arm/arm.c >> +++ b/virt/kvm/arm/arm.c >> @@ -335,7 +335,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) >> >> kvm_arm_reset_debug_ptr(vcpu); >> >> - return 0; >> + return kvm_vgic_vcpu_init(vcpu); >> } >> >> void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) >> diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c >> index 0ea64a1..962bb57 100644 >> --- a/virt/kvm/arm/vgic/vgic-init.c >> +++ b/virt/kvm/arm/vgic/vgic-init.c >> @@ -226,6 +226,27 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis) >> return 0; >> } >> >> +/** >> + * kvm_vgic_vcpu_init() - Register VCPU-specific KVM iodevs >> + * @vcpu: pointer to the VCPU being created and initialized >> + */ >> +int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) >> +{ >> + int ret = 0; >> + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; >> + >> + if (!irqchip_in_kernel(vcpu->kvm)) >> + return 0; >> + >> + /* >> + * If we are creating a VCPU with a GICv3 we must also register the >> + * KVM io device for the redistributor that belongs to this VCPU. >> + */ >> + if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3) >> + ret = vgic_register_redist_iodev(vcpu); >> + return ret; >> +} >> + >> static void kvm_vgic_vcpu_enable(struct kvm_vcpu *vcpu) >> { >> if (kvm_vgic_global_state.type == VGIC_V2) >> diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c >> index 69ccfd5..10ae6f3 100644 >> --- a/virt/kvm/arm/vgic/vgic-kvm-device.c >> +++ b/virt/kvm/arm/vgic/vgic-kvm-device.c >> @@ -86,8 +86,13 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write) >> break; >> case KVM_VGIC_V3_ADDR_TYPE_REDIST: >> r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3); >> + if (r) >> + break; >> + if (write) { >> + r = vgic_v3_set_redist_base(kvm, *addr); >> + goto out; >> + } >> addr_ptr = &vgic->vgic_redist_base; >> - alignment = SZ_64K; >> break; >> default: >> r = -ENODEV; >> diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c >> index 168269b..99da1a2 100644 >> --- a/virt/kvm/arm/vgic/vgic-mmio-v3.c >> +++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c >> @@ -565,7 +565,7 @@ unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev) >> * >> * Return 0 on success, -ERRNO otherwise. >> */ >> -static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) >> +int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) >> { >> struct kvm *kvm = vcpu->kvm; >> struct vgic_dist *vgic = &kvm->arch.vgic; >> @@ -574,6 +574,18 @@ static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu) >> gpa_t rd_base, sgi_base; >> int ret; >> >> + /* >> + * We may be creating VCPUs before having set the base address for the >> + * redistributor region, in which case we will come back to this >> + * function for all VCPUs when the base address is set. Just return >> + * without doing any work for now. >> + */ >> + if (IS_VGIC_ADDR_UNDEF(vgic->vgic_redist_base)) >> + return 0; >> + >> + if (!vgic_v3_check_base(kvm)) >> + return -EINVAL; >> + >> rd_base = vgic->vgic_redist_base + kvm_vcpu_get_idx(vcpu) * SZ_64K * 2; >> sgi_base = rd_base + SZ_64K; >> >> @@ -619,7 +631,7 @@ static void vgic_unregister_redist_iodev(struct kvm_vcpu *vcpu) >> kvm_io_bus_unregister_dev(vcpu->kvm, KVM_MMIO_BUS, &sgi_dev->dev); >> } >> >> -int vgic_register_redist_iodevs(struct kvm *kvm) >> +static int vgic_register_all_redist_iodevs(struct kvm *kvm) >> { >> struct kvm_vcpu *vcpu; >> int c, ret = 0; >> @@ -641,6 +653,33 @@ int vgic_register_redist_iodevs(struct kvm *kvm) >> return ret; >> } >> >> +int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr) >> +{ >> + struct vgic_dist *vgic = &kvm->arch.vgic; >> + int ret; >> + >> + /* vgic_check_ioaddr makes sure we don't do this twice */ >> + ret = vgic_check_ioaddr(kvm, &vgic->vgic_redist_base, addr, SZ_64K); >> + if (ret) >> + return ret; >> + >> + vgic->vgic_redist_base = addr; >> + if (!vgic_v3_check_base(kvm)) { >> + vgic->vgic_redist_base = VGIC_ADDR_UNDEF; >> + return -EINVAL; >> + } >> + >> + /* >> + * Register iodevs for each existing VCPU. Adding more VCPUs >> + * afterwards will register the iodevs when needed. >> + */ >> + ret = vgic_register_all_redist_iodevs(kvm); >> + if (ret) >> + return ret; >> + >> + return 0; >> +} >> + >> int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr) >> { >> const struct vgic_register_region *region; >> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c >> index 2d53d7a..bb35078 100644 >> --- a/virt/kvm/arm/vgic/vgic-v3.c >> +++ b/virt/kvm/arm/vgic/vgic-v3.c >> @@ -397,12 +397,6 @@ int vgic_v3_map_resources(struct kvm *kvm) >> goto out; >> } >> >> - ret = vgic_register_redist_iodevs(kvm); >> - if (ret) { >> - kvm_err("Unable to register VGICv3 redist MMIO regions\n"); >> - goto out; >> - } >> - >> if (vgic_has_its(kvm)) { >> ret = vgic_register_its_iodevs(kvm); >> if (ret) { >> diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h >> index 89eb935..5f17eac 100644 >> --- a/virt/kvm/arm/vgic/vgic.h >> +++ b/virt/kvm/arm/vgic/vgic.h >> @@ -174,7 +174,8 @@ int vgic_v3_probe(const struct gic_kvm_info *info); >> int vgic_v3_map_resources(struct kvm *kvm); >> int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq); >> int vgic_v3_save_pending_tables(struct kvm *kvm); >> -int vgic_register_redist_iodevs(struct kvm *kvm); >> +int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr); >> +int vgic_register_redist_iodev(struct kvm_vcpu *vcpu); >> bool vgic_v3_check_base(struct kvm *kvm); >> >> void vgic_v3_load(struct kvm_vcpu *vcpu); >> > > _______________________________________________ > kvmarm mailing list > kvmarm at lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/kvmarm >