Re: [PATCH v6 1/2] xen/pvh: use a custom IO bitmap for PVH hardware domains

From: "Jan Beulich" <JBeulich@suse.com>
To: Roger Pau Monne <roger.pau@citrix.com>
Cc: Kevin Tian <kevin.tian@intel.com>,
	Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	Eddie Dong <eddie.dong@intel.com>,
	Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>,
	Jun Nakajima <jun.nakajima@intel.com>,
	xen-devel@lists.xenproject.org,
	Boris Ostrovsky <boris.ostrovsky@oracle.com>
Subject: Re: [PATCH v6 1/2] xen/pvh: use a custom IO bitmap for PVH hardware domains
Date: Wed, 13 May 2015 10:53:06 +0100	[thread overview]
Message-ID: <55533B220200007800079F0A@mail.emea.novell.com> (raw)
In-Reply-To: <1431356258-31269-2-git-send-email-roger.pau@citrix.com>

>>> On 11.05.15 at 16:57, <roger.pau@citrix.com> wrote:
> --- a/xen/arch/x86/setup.c
> +++ b/xen/arch/x86/setup.c
> @@ -1446,6 +1446,9 @@ void __init noreturn __start_xen(unsigned long mbi_p)
>  
>      dmi_end_boot();
>  
> +    if ( is_hardware_domain(dom0) )
> +        setup_io_bitmap(dom0);

Is it indeed possible for is_hardware_domain() to be false for dom0
at this point?

> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -42,6 +42,7 @@
>  #include <xsm/xsm.h>
>  #include <xen/trace.h>
>  #include <xen/tmem.h>
> +#include <asm/setup.h>
>  
>  /* Linux config option: propageted to domain0 */
>  /* xen_processor_pmbits: xen control Cx, Px, ... */
> @@ -219,6 +220,7 @@ static int late_hwdom_init(struct domain *d)
>      rangeset_swap(d->iomem_caps, dom0->iomem_caps);
>  #ifdef CONFIG_X86
>      rangeset_swap(d->arch.ioport_caps, dom0->arch.ioport_caps);
> +    setup_io_bitmap(d);
>  #endif

Considering that rangesets are getting swapped rather than
copied, I think you also need to reset Dom0's I/O bitmap here
to the ordinary, non-hardware domain one.

Jan