Re: [Qemu-devel] [PATCH v3 01/19] target-i386: cpu: use uint32_t for X86CPU.apic_id

[Bandan Das <bsd@redhat.com>]

I know some of these have already been pulled. I just have some minor
questions/comments that shouldn't conflict.

Igor Mammedov <imammedo@redhat.com> writes:

> Redo 9886e834 (target-i386: Require APIC ID to be explicitly set before
> CPU realize) in another way that doesn't use int64_t to detect
> if apic-id property has been set.
>
> Use the fact that 0xFFFFFFFF is the broadcast

I noticed this was UINT32_MAX in v2. Why is UINT32_MAX
not appropriate ?

> value that a CPU can't have and set default
> uint32_t apic_id to it instead of using int64_t.
>
> Later uint32_t apic_id will be used to drop custom
> property setter/getter in favor of static property.
>
> Signed-off-by: Igor Mammedov <imammedo@redhat.com>
> ---
>  target-i386/cpu.c | 4 ++--
>  target-i386/cpu.h | 7 ++++++-
>  2 files changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/target-i386/cpu.c b/target-i386/cpu.c
> index 5c69c43..e7319e3 100644
> --- a/target-i386/cpu.c
> +++ b/target-i386/cpu.c
> @@ -2883,7 +2883,7 @@ static void x86_cpu_realizefn(DeviceState *dev, Error **errp)
>          goto out;
>      }
>  
> -    if (cpu->apic_id < 0) {
> +    if (cpu->apic_id == UNASSIGNED_APIC_ID) {
>          error_setg(errp, "apic-id property was not initialized properly");
>          return;
>      }
> @@ -3154,7 +3154,7 @@ static void x86_cpu_initfn(Object *obj)
>  
>  #ifndef CONFIG_USER_ONLY
>      /* Any code creating new X86CPU objects have to set apic-id explicitly */
> -    cpu->apic_id = -1;
> +    cpu->apic_id = UNASSIGNED_APIC_ID;
>  #endif
>  
>      for (w = 0; w < FEATURE_WORDS; w++) {
> diff --git a/target-i386/cpu.h b/target-i386/cpu.h
> index 738958e..00de199 100644
> --- a/target-i386/cpu.h
> +++ b/target-i386/cpu.h
> @@ -835,6 +835,11 @@ typedef struct {
>  
>  #define NB_OPMASK_REGS 8
>  
> +/* CPU can't have 0xFFFFFFFF APIC ID, use that value to distinguish
> + * that APIC ID hasn't been set yet
> + */
> +#define UNASSIGNED_APIC_ID 0xFFFFFFFF
> +
>  typedef union X86LegacyXSaveArea {
>      struct {
>          uint16_t fcw;
> @@ -1163,7 +1168,7 @@ struct X86CPU {
>      bool expose_kvm;
>      bool migratable;
>      bool host_features;
> -    int64_t apic_id;
> +    uint32_t apic_id;
>  
>      /* if true the CPUID code directly forward host cache leaves to the guest */
>      bool cache_info_passthrough;