Re: [PATCH V10 02/14] xen/pvh: Extend vcpu_guest_context, p2m, event, and XenBus.

[David Vrabel <david.vrabel@citrix.com>]

On 13/12/13 02:10, Konrad Rzeszutek Wilk wrote:
> From: Mukesh Rathor <mukesh.rathor@oracle.com>
> 
> Make gdt_frames[]/gdt_ents into a union with {gdtaddr, gdtsz},
> as PVH only needs to send down gdtaddr and gdtsz in the
> vcpu_guest_context structure..
> 
> For interrupts, PVH uses native_irq_ops so we can skip most of the
> PV ones. In the future we can support the pirq_eoi_map..
> Also VCPU hotplug is currently not available for PVH.
> 
> For events (and IRQs) we follow what PVHVM does - so use callback
> vector.  Lastly, for XenBus we use the same logic that is used in
> the PVHVM case.
[...]
> --- a/arch/x86/include/asm/xen/interface.h
> +++ b/arch/x86/include/asm/xen/interface.h
> @@ -145,7 +145,16 @@ struct vcpu_guest_context {
>      struct cpu_user_regs user_regs;         /* User-level CPU registers     */
>      struct trap_info trap_ctxt[256];        /* Virtual IDT                  */
>      unsigned long ldt_base, ldt_ents;       /* LDT (linear address, # ents) */
> -    unsigned long gdt_frames[16], gdt_ents; /* GDT (machine frames, # ents) */
> +    union {
> +	struct {
> +		/* PV: GDT (machine frames, # ents).*/
> +		unsigned long gdt_frames[16], gdt_ents;
> +	} pv;
> +	struct {
> +		/* PVH: GDTR addr and size */
> +		unsigned long gdtaddr, gdtsz;
> +	} pvh;
> +    } u;

Doesn't match the hypervisor.

> --- a/arch/x86/xen/p2m.c
> +++ b/arch/x86/xen/p2m.c
> @@ -800,8 +800,10 @@ bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
>  	unsigned topidx, mididx, idx;
>  
>  	/* don't track P2M changes in autotranslate guests */
> -	if (unlikely(xen_feature(XENFEAT_auto_translated_physmap)))
> +	if (unlikely(xen_feature(XENFEAT_auto_translated_physmap))) {
> +		BUG_ON(pfn != mfn && mfn != INVALID_P2M_ENTRY);
>  		return true;
> +	}

Isn't this undoing a recent change that removed this BUG_ON()?

David