tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1Generic vcpu interface
2====================================
3
4The virtual cpu "device" also accepts the ioctls KVM_SET_DEVICE_ATTR,
5KVM_GET_DEVICE_ATTR, and KVM_HAS_DEVICE_ATTR. The interface uses the same struct
6kvm_device_attr as other devices, but targets VCPU-wide settings and controls.
7
8The groups and attributes per virtual cpu, if any, are architecture specific.
9
101. GROUP: KVM_ARM_VCPU_PMU_V3_CTRL
11Architectures: ARM64
12
131.1. ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_IRQ
14Parameters: in kvm_device_attr.addr the address for PMU overflow interrupt is a
15 pointer to an int
16Returns: -EBUSY: The PMU overflow interrupt is already set
17 -ENXIO: The overflow interrupt not set when attempting to get it
18 -ENODEV: PMUv3 not supported
19 -EINVAL: Invalid PMU overflow interrupt number supplied or
20 trying to set the IRQ number without using an in-kernel
21 irqchip.
22
23A value describing the PMUv3 (Performance Monitor Unit v3) overflow interrupt
24number for this vcpu. This interrupt could be a PPI or SPI, but the interrupt
25type must be same for each vcpu. As a PPI, the interrupt number is the same for
26all vcpus, while as an SPI it must be a separate number per vcpu.
27
281.2 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_INIT
29Parameters: no additional parameter in kvm_device_attr.addr
30Returns: -ENODEV: PMUv3 not supported or GIC not initialized
31 -ENXIO: PMUv3 not properly configured or in-kernel irqchip not
32 configured as required prior to calling this attribute
33 -EBUSY: PMUv3 already initialized
34
35Request the initialization of the PMUv3. If using the PMUv3 with an in-kernel
36virtual GIC implementation, this must be done after initializing the in-kernel
37irqchip.
38
39
402. GROUP: KVM_ARM_VCPU_TIMER_CTRL
41Architectures: ARM,ARM64
42
432.1. ATTRIBUTE: KVM_ARM_VCPU_TIMER_IRQ_VTIMER
442.2. ATTRIBUTE: KVM_ARM_VCPU_TIMER_IRQ_PTIMER
45Parameters: in kvm_device_attr.addr the address for the timer interrupt is a
46 pointer to an int
47Returns: -EINVAL: Invalid timer interrupt number
48 -EBUSY: One or more VCPUs has already run
49
50A value describing the architected timer interrupt number when connected to an
51in-kernel virtual GIC. These must be a PPI (16 <= intid < 32). Setting the
52attribute overrides the default values (see below).
53
54KVM_ARM_VCPU_TIMER_IRQ_VTIMER: The EL1 virtual timer intid (default: 27)
55KVM_ARM_VCPU_TIMER_IRQ_PTIMER: The EL1 physical timer intid (default: 30)
56
57Setting the same PPI for different timers will prevent the VCPUs from running.
58Setting the interrupt number on a VCPU configures all VCPUs created at that
59time to use the number provided for a given timer, overwriting any previously
60configured values on other VCPUs. Userspace should configure the interrupt
61numbers on at least one VCPU after creating all VCPUs and before running any
62VCPUs.