2016-10-24 22:32 GMT+08:00 Paolo Bonzini <pbonz...@redhat.com>: > > > On 19/10/2016 16:30, Wanpeng Li wrote: >> Cc Radim, >> 2016-10-19 22:10 GMT+08:00 Paolo Bonzini <pbonz...@redhat.com>: >>> >>> >>> On 19/10/2016 16:01, Wanpeng Li wrote: >>>> 2016-10-18 8:01 GMT+08:00 Wanpeng Li <kernel...@gmail.com>: >>>>> 2016-10-17 18:08 GMT+08:00 Paolo Bonzini <pbonz...@redhat.com>: >>>>> [...] >>>>>>>> Something like the below avoids all that. Paravirt will still need >>>>>>>> fixing. >>>>>>> >>>>>>> kvm_guest_apic_eoi_write >>>>>>> -> native_apic_msr_write >>>>>> >>>>>> kvm_guest_apic_eoi_write can use native_apic_msr_eoi_write too: >>>>>> >>>>>> diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h >>>>>> index f5aaf6c83222..9769d76a62c4 100644 >>>>>> --- a/arch/x86/include/asm/apic.h >>>>>> +++ b/arch/x86/include/asm/apic.h >>>>>> @@ -174,7 +174,7 @@ static inline void disable_local_APIC(void) { } >>>>>> static inline void lapic_update_tsc_freq(void) { } >>>>>> #endif /* !CONFIG_X86_LOCAL_APIC */ >>>>>> >>>>>> -#ifdef CONFIG_X86_X2APIC >>>>>> +#if defined CONFIG_X86_X2APIC || defined CONFIG_KVM_GUEST >>>>> >>>>> If CONFIG_X86_X2APIC is undefined and CONFIG_KVM_GUEST is defined, >>>>> there are undefined reference warning for x2apic_mode and check_x2apic >>>>> etc since they are extern variables and just define under >>>>> CONFIG_X86_X2APIC. >>>> >> >> This results in undefined reference warning. >> >>>> >>>>> >>>>> If -cpu host,-x2apic we should go through mmio when writes xapic EOI. >>>> >>>> Any ideas? :) >>> >>> Make apic_set_eoi_write return the old pointer? >> >> Could you elaborate? :) > > No, that won't work due to how struct apic works and how > apic_set_eoi_write patches it. One possibility then is to add a > > void (*native_eoi_write)(u32 reg, u32 v); > > field to struct apic, and make apic_set_eoi_write set > > (*drv)->native_eoi_write = (*drv)->eoi_write; > (*drv)->eoi_write = eoi_write; > > Then kvm.c can call > > apic->native_eoi_write(reg, v);
It works. Thanks Paolo. :) Regards, Wanpeng Li