diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/virtual/kvm/api.txt | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 0d14bf5db534..89e71648d748 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -3642,7 +3642,7 @@ KVM handlers should exit to userspace with rc = -EREMOTE. 7.5 KVM_CAP_SPLIT_IRQCHIP Architectures: x86 -Parameters: None +Parameters: args[0] - number of routes reserved for userspace IOAPICs Returns: 0 on success, -1 on error Create a local apic for each processor in the kernel. This can be used @@ -3650,8 +3650,11 @@ instead of KVM_CREATE_IRQCHIP if the userspace VMM wishes to emulate the IOAPIC and PIC (and also the PIT, even though this has to be enabled separately). -This supersedes KVM_CREATE_IRQCHIP, creating only local APICs, but no in kernel -IOAPIC or PIC. This also enables in kernel routing of interrupt requests. +This capability also enables in kernel routing of interrupt requests; +when KVM_CAP_SPLIT_IRQCHIP only routes of KVM_IRQ_ROUTING_MSI type are +used in the IRQ routing table. The first args[0] MSI routes are reserved +for the IOAPIC pins. Whenever the LAPIC receives an EOI for these routes, +a KVM_EXIT_IOAPIC_EOI vmexit will be reported to userspace. Fails if VCPU has already been created, or if the irqchip is already in the kernel (i.e. KVM_CREATE_IRQCHIP has already been called). |