On 22/05/2015 19:22, Radim Krčmář wrote: > Logical x2APIC stops working if we rewrite it with zeros. > The best references are SDM April 2015: 10.12.10.1 Logical Destination > Mode in x2APIC Mode > > [...], the LDR are initialized by hardware based on the value of > x2APIC ID upon x2APIC state transitions. > > and SDM April 2015: 10.12.10.2 Deriving Logical x2APIC ID from the Local > x2APIC ID > > The LDR initialization occurs whenever the x2APIC mode is enabled > > Signed-off-by: Radim Krčmář <rkrcmar@xxxxxxxxxx> > --- > arch/x86/kvm/lapic.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index c2a7d8a7a414..c789e00dfa8b 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -1594,7 +1594,8 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event) > apic_set_reg(apic, APIC_DFR, 0xffffffffU); > apic_set_spiv(apic, 0xff); > apic_set_reg(apic, APIC_TASKPRI, 0); > - kvm_apic_set_ldr(apic, 0); > + if (!apic_x2apic_mode(apic)) > + kvm_apic_set_ldr(apic, 0); > apic_set_reg(apic, APIC_ESR, 0); > apic_set_reg(apic, APIC_ICR, 0); > apic_set_reg(apic, APIC_ICR2, 0); > Applied, thanks. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
