Re: [Xen-devel] [PATCH V2 9/25] tools/libxl: build DMAR table for a guest with one virtual VTD

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Thu, Aug 24, 2017 at 11:24:12AM +0800, Lan Tianyu wrote:
> On 2017年08月23日 16:34, Wei Liu wrote:
> >>>
> >>> I would like the code to generate dmar take into consideration
> >>> libxl__dom_load_acpi.
> >>>
> >>
> >> If add dmar table for hvmlite, we should combine dmar table with other
> >> ACPI table and populate into acpi_modules[2]. This is how hvmlite add
> >> other ACPI tables in libxl__dom_load_acpi().
> >>
> > 
> > Sure, that sounds plausible.
> > 
> > What I would like to see is to have one entry point to manipulate APCI
> > tables.
> > 
> > Given the patch volume we're seeing now, we expect contributors to drive
> > the discussion forward. If you're not sure, feel free to ask more questions.
> 
> I am not sure whether I understood correctly.
> 
> PVHv2 builds all ACPI table in tool stack and uses acpi_module[0, 1, 2]
> to pass related table content.
> 
> HVM builds ACPI tables in hvmloader and just use acpi_module[0] to pass
> additional ACPI firmware or table.
> 
> These two modes have different way to use acpi_modules[]. So I think we
> can't combine them, right?
> 

There might be some misunderstanding.  We probably don't want to
manipulate the content of the tables in libxl.

> For build dmar table, we have introduced construct_dmar() in under
> libacpi to build dmar table and PVHv2 also can use it in
> libxl__dom_load_acpi().
> 

My major complain is now there are two functions and in two different
locations, in two different phases of domain construction that would
manipulate ACPI tables. I would like to have only one.

The function you're currently modifying libxl__domain_firmware is not
the right place. It's primary function is to load files from disks.

You should be able to call the function you introduced in
libxl__dom_load_acpi, provided appropriate checks are added.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel