[PATCH 2/2] KVM: LAPIC: Set the TDCR settable bits

From: Wanpeng Li
Date: Tue Jul 21 2020 - 05:24:45 EST


From: Wanpeng Li <wanpengli@xxxxxxxxxxx>

Only bits 0, 1, and 3 are settable, others are reserved for APIC_TDCR.
Let's record the settable value in the virtual apic page.

Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
---
arch/x86/kvm/lapic.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 4ce2ddd..8f7a14d 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2068,7 +2068,7 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
case APIC_TDCR: {
uint32_t old_divisor = apic->divide_count;

- kvm_lapic_set_reg(apic, APIC_TDCR, val);
+ kvm_lapic_set_reg(apic, APIC_TDCR, val & 0xb);
update_divide_count(apic);
if (apic->divide_count != old_divisor &&
apic->lapic_timer.period) {
--
2.7.4