Mark APIC_DFR as being invalid/non-existent in x2APIC mode instead of handling it as a one-off check in kvm_x2apic_msr_read(). This will allow reusing "valid_reg_mask" to generate VMX's interception bitmaps for x2APIC. Handling DFR in the common read path may also fix the Hyper-V PV MSR interface, if that can coexist with x2APIC. Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> --- arch/x86/kvm/lapic.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index bf53e4752f30..c49b13418638 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1541,7 +1541,6 @@ static int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len, APIC_REG_MASK(APIC_TASKPRI) | APIC_REG_MASK(APIC_PROCPRI) | APIC_REG_MASK(APIC_LDR) | - APIC_REG_MASK(APIC_DFR) | APIC_REG_MASK(APIC_SPIV) | APIC_REGS_MASK(APIC_ISR, APIC_ISR_NR) | APIC_REGS_MASK(APIC_TMR, APIC_ISR_NR) | @@ -1562,12 +1561,13 @@ static int kvm_lapic_reg_read(struct kvm_lapic *apic, u32 offset, int len, valid_reg_mask |= APIC_REG_MASK(APIC_LVTCMCI); /* - * ARBPRI and ICR2 are not valid in x2APIC mode. WARN if KVM reads ICR - * in x2APIC mode as it's an 8-byte register in x2APIC and needs to be - * manually handled by the caller. + * ARBPRI, DFR, and ICR2 are not valid in x2APIC mode. WARN if KVM + * reads ICR in x2APIC mode as it's an 8-byte register in x2APIC and + * needs to be manually handled by the caller. */ if (!apic_x2apic_mode(apic)) valid_reg_mask |= APIC_REG_MASK(APIC_ARBPRI) | + APIC_REG_MASK(APIC_DFR) | APIC_REG_MASK(APIC_ICR2); else WARN_ON_ONCE(offset == APIC_ICR); @@ -3141,9 +3141,6 @@ int kvm_x2apic_msr_read(struct kvm_vcpu *vcpu, u32 msr, u64 *data) if (!lapic_in_kernel(vcpu) || !apic_x2apic_mode(apic)) return 1; - if (reg == APIC_DFR) - return 1; - return kvm_lapic_msr_read(apic, reg, data); } -- 2.39.0.314.g84b9a713c41-goog
