Re: [Qemu-devel] [PATCH v2 06/11] nvdimm acpi: initialize the resource used by NVDIMM ACPI

[Igor Mammedov]

On Sun, 14 Feb 2016 13:57:27 +0800
Xiao Guangrong <address@hidden> wrote:

> On 02/08/2016 07:03 PM, Igor Mammedov wrote:
> > On Wed, 13 Jan 2016 02:50:05 +0800
> > Xiao Guangrong <address@hidden> wrote:
> >  
> >> 32 bits IO port starting from 0x0a18 in guest is reserved for NVDIMM
> >> ACPI emulation. The table, NVDIMM_DSM_MEM_FILE, will be patched into
> >> NVDIMM ACPI binary code
> >>
> >> OSPM uses this port to tell QEMU the final address of the DSM memory
> >> and notify QEMU to emulate the DSM method  
> > Would you need to pass control to QEMU if each NVDIMM had its whole
> > label area MemoryRegion mapped right after its storage MemoryRegion?
> >  
> 
> No, label data is not mapped into guest's address space and it only
> can be accessed by DSM method indirectly.
Yep, per spec label data should be accessed via _DSM but question
wasn't about it,
Why would one map only 4Kb window and serialize label data
via it if it could be mapped as whole, that way _DMS method will be
much less complicated and there won't be need to add/support a protocol
for its serialization.