diff options
author | Chao Gao <chao.gao@intel.com> | 2022-04-19 23:45:10 +0800 |
---|---|---|
committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-06-08 04:47:37 -0400 |
commit | d588bb9be1da6aa750aa64875fe57369db983d8b (patch) | |
tree | 24f7f00b1121cdffad0bb10e5dd107de550bc97d /arch/x86/kvm/vmx/vmx.h | |
parent | 753dcf7a8686a750fa6aa4b4ca42c6945fc75ac1 (diff) | |
download | linux-d588bb9be1da6aa750aa64875fe57369db983d8b.tar.bz2 |
KVM: VMX: enable IPI virtualization
With IPI virtualization enabled, the processor emulates writes to
APIC registers that would send IPIs. The processor sets the bit
corresponding to the vector in target vCPU's PIR and may send a
notification (IPI) specified by NDST and NV fields in target vCPU's
Posted-Interrupt Descriptor (PID). It is similar to what IOMMU
engine does when dealing with posted interrupt from devices.
A PID-pointer table is used by the processor to locate the PID of a
vCPU with the vCPU's APIC ID. The table size depends on maximum APIC
ID assigned for current VM session from userspace. Allocating memory
for PID-pointer table is deferred to vCPU creation, because irqchip
mode and VM-scope maximum APIC ID is settled at that point. KVM can
skip PID-pointer table allocation if !irqchip_in_kernel().
Like VT-d PI, if a vCPU goes to blocked state, VMM needs to switch its
notification vector to wakeup vector. This can ensure that when an IPI
for blocked vCPUs arrives, VMM can get control and wake up blocked
vCPUs. And if a VCPU is preempted, its posted interrupt notification
is suppressed.
Note that IPI virtualization can only virualize physical-addressing,
flat mode, unicast IPIs. Sending other IPIs would still cause a
trap-like APIC-write VM-exit and need to be handled by VMM.
Signed-off-by: Chao Gao <chao.gao@intel.com>
Signed-off-by: Zeng Guang <guang.zeng@intel.com>
Message-Id: <20220419154510.11938-1-guang.zeng@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.h')
-rw-r--r-- | arch/x86/kvm/vmx/vmx.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index c37befcea2c0..d7baedda79e5 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -366,6 +366,8 @@ struct kvm_vmx { unsigned int tss_addr; bool ept_identity_pagetable_done; gpa_t ept_identity_map_addr; + /* Posted Interrupt Descriptor (PID) table for IPI virtualization */ + u64 *pid_table; }; bool nested_vmx_allowed(struct kvm_vcpu *vcpu); @@ -581,4 +583,9 @@ static inline int vmx_get_instr_info_reg2(u32 vmx_instr_info) return (vmx_instr_info >> 28) & 0xf; } +static inline bool vmx_can_use_ipiv(struct kvm_vcpu *vcpu) +{ + return lapic_in_kernel(vcpu) && enable_ipiv; +} + #endif /* __KVM_X86_VMX_H */ |