Re: [PATCH 1/3] x86/Hyper-V: Set x2apic destination mode to physical when x2apic is available

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Jan 31, 2019 at 06:17:31PM +0800, lantianyu1986@gmail.com wrote:
> From: Lan Tianyu <Tianyu.Lan@microsoft.com>
> 
> Hyper-V doesn't provide irq remapping for IO-APIC. To enable x2apic,
> set x2apic destination mode to physcial mode when x2apic is available
> and Hyper-V IOMMU driver makes sure cpus assigned with IO-APIC irqs have
> 8-bit APIC id.
> 
> Signed-off-by: Lan Tianyu <Tianyu.Lan@microsoft.com>
> ---
>  arch/x86/kernel/cpu/mshyperv.c | 14 ++++++++++++++
>  1 file changed, 14 insertions(+)
> 
> diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
> index e81a2db..9d62f33 100644
> --- a/arch/x86/kernel/cpu/mshyperv.c
> +++ b/arch/x86/kernel/cpu/mshyperv.c
> @@ -36,6 +36,8 @@
>  struct ms_hyperv_info ms_hyperv;
>  EXPORT_SYMBOL_GPL(ms_hyperv);
>  
> +extern int x2apic_phys;

Shouldn't this be in a .h file somewhere instead?

thanks,

greg k-h