[Xen-devel] [PATCH] Inclusing memory mapping of all 4GB for dom0 iommu mappings

[Ross Philipson <Ross.Philipson@xxxxxxxxxx>]

The previous patch is not quite correct. It still doesn’t handle

the case where max_page (derived from the max E820_RAM value) which

could be less than a reserved range (as was pointed out in an earlier

email). If that range did not have a correct RMRR then again the

workaround would miss it.

 

This patch changes it so all memory below 4GB is mapped when the

parameter is set (minus unusable and xen range).

 

Signed-off-by: Ross Philipson <ross.philipson@xxxxxxxxxx>

 

Based on changeset 19267

 

Thanks

Ross

 

 

From: Ross Philipson
Sent: Sunday, March 01, 2009 4:49 PM
To: 'xen-devel@xxxxxxxxxxxxxxxxxxx'
Subject: [PATCH] Inclusing memory mapping param for dom0 iommu mappings

 

OK, cut two of the iommu reserved memory issue patch as we discussed...

 

This patch adds a boolean boot parameter to xen to allow inclusive

mapping of all memory below 4GB to the iommu mappings for dom0. The

unusable ranges and memory occupied by xen are still excluded. The

parameter is “iommu_inclusive_mapping=1” and is off by default. In

addition to the parameter, a warning is also traced when incorrect

RMRR to system memory map values are detected. These are being added

to address some incorrect BIOS's that do not report correctly the

requied reserved memory ranges in the RMRRs. When this occurs it

currently can cause early boot hangs and crashes.

 

Signed-off-by: Ross Philipson <ross.philipson@xxxxxxxxxx>

 

Based on changeset 19243

 

Thanks

Ross

 

 

Ross Philipson

Senior Software Engineer

Citrix Systems, Inc

14 Crosby Drive

Bedford, MA 01730

781-301-7949

ross.philipson@xxxxxxxxxx

 

iommu_include_4gb.patch
Description: iommu_include_4gb.patch

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel