On 1/6/2022 3:13 AM, Tom Lendacky wrote:
On 12/31/21 8:28 AM, Zeng Guang wrote:
In xAPIC mode, guest is allowed to modify APIC ID at runtime.
If IPI virtualization is enabled, corresponding entry in
PID-pointer table need change accordingly.
Signed-off-by: Zeng Guang <guang.zeng@xxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/lapic.c | 7 +++++--
arch/x86/kvm/vmx/vmx.c | 12 ++++++++++++
3 files changed, 18 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 2164b9f4c7b0..753bf2a7cebc 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1493,6 +1493,7 @@ struct kvm_x86_ops {
int (*complete_emulated_msr)(struct kvm_vcpu *vcpu, int err);
void (*vcpu_deliver_sipi_vector)(struct kvm_vcpu *vcpu, u8 vector);
+ void (*update_ipiv_pid_entry)(struct kvm_vcpu *vcpu, u8 old_id, u8 new_id);
};
struct kvm_x86_nested_ops {
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 3ce7142ba00e..83c2c7594bcd 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2007,9 +2007,12 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
switch (reg) {
case APIC_ID: /* Local APIC ID */
- if (!apic_x2apic_mode(apic))
+ if (!apic_x2apic_mode(apic)) {
+ u8 old_id = kvm_lapic_get_reg(apic, APIC_ID) >> 24;
+
kvm_apic_set_xapic_id(apic, val >> 24);
- else
+ kvm_x86_ops.update_ipiv_pid_entry(apic->vcpu, old_id, val >> 24);
Won't this blow up on AMD since there is no corresponding SVM op?
Thanks,
Tom
Right, need check ops validness to avoid ruining AMD system. Same
consideration on ops "update_ipiv_pid_table" in patch8.
I will revise in next version. Thanks.
+ } else
ret = 1;
break;
