Re: [Qemu-devel] [PATCH] pc: fix KVM features in pc-1.3 and earlier machine types

[Paolo Bonzini <pbonzini@redhat.com>]

On 19/01/2015 19:13, Andreas Färber wrote:
> Am 19.01.2015 um 12:24 schrieb Paolo Bonzini:
>> Due to a typo, instead of disabling KVM_FEATURE_PV_EOI (bit
>> 6) these machine types are disabling bits 1 and 2, which are
>> KVM_FEATURE_NOP_IO_DELAY and KVM_FEATURE_MMU_OP.  Not a big deal
>> because they aren't very important and KVM_FEATURE_MMU_OP is
>> disabled anyway.  The worst part is actually that KVM_FEATURE_PV_EOI
>> is remaining enabled.
>>
>> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
>> ---
>>  hw/i386/pc_piix.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
>> index f0a3201..97a754e 100644
>> --- a/hw/i386/pc_piix.c
>> +++ b/hw/i386/pc_piix.c
>> @@ -406,7 +406,7 @@ static void pc_compat_1_3(MachineState *machine)
>>  static void pc_compat_1_2(MachineState *machine)
>>  {
>>      pc_compat_1_3(machine);
>> -    x86_cpu_compat_kvm_no_autoenable(FEAT_KVM, KVM_FEATURE_PV_EOI);
>> +    x86_cpu_compat_kvm_no_autoenable(FEAT_KVM, 1 << KVM_FEATURE_PV_EOI);
>>  }
>>  
>>  static void pc_init_pci_2_2(MachineState *machine)
>> @@ -483,7 +483,7 @@ static void pc_init_isa(MachineState *machine)
>>      if (!machine->cpu_model) {
>>          machine->cpu_model = "486";
>>      }
>> -    x86_cpu_compat_kvm_no_autoenable(FEAT_KVM, KVM_FEATURE_PV_EOI);
>> +    x86_cpu_compat_kvm_no_autoenable(FEAT_KVM, 1 << KVM_FEATURE_PV_EOI);
>>      enable_compat_apic_id_mode();
>>      pc_init1(machine, 0, 1);
>>  }
> 
> Might it make sense to tweak that helper function instead to avoid this
> reoccurring? Either way, no objection, please apply through kvm queue.

Will do.  The problem is that the same function is used for CPUID_*
defines that _are_ bitmasks.

Paolo