Re: port-xen/57121: Pure NetBSD PVH guests do not appear to be able to use more than 4GB of memory

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

The following reply was made to PR port-xen/57121; it has been noted by GNATS.

From: Manuel Bouyer <bouyer%antioche.eu.org@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: port-xen-maintainer%netbsd.org@localhost, gnats-admin%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost
Subject: Re: port-xen/57121: Pure NetBSD PVH guests do not appear to be able
 to use more than 4GB of memory
Date: Fri, 23 Dec 2022 17:08:19 +0100

 --cKygguVIx5P7Hdxx
 Content-Type: text/plain; charset=us-ascii
 Content-Disposition: inline
 
 On Mon, Dec 19, 2022 at 03:20:00PM +0000, brad%anduin.eldar.org@localhost wrote:
 > With a pure PVH 64bit NetBSD guest using the GENERIC kernel, the guest
 > does not appear to be able to use more than 4GB of memory.  That is,
 > no matter how much memory you give the guest the guest caps it at 4GB.
 > This does not happen with ArchLinux guests on the same DOM0.  The same
 > guest configured as a PV system with pvshim sees all of the memory.
 
 Hello
 I just commited the attached patch to HEAD; it should apply cleanly to
 netbsd-10 too. Can you test ?
 I can't test with much more than 4GB on my devel box (not enough RAM) ...
 
 -- 
 Manuel Bouyer <bouyer%antioche.eu.org@localhost>
      NetBSD: 26 ans d'experience feront toujours la difference
 --
 
 --cKygguVIx5P7Hdxx
 Content-Type: text/plain; charset=us-ascii
 Content-Disposition: attachment; filename=diff
 
 Index: x86/x86/x86_machdep.c
 ===================================================================
 RCS file: /cvsroot/src/sys/arch/x86/x86/x86_machdep.c,v
 retrieving revision 1.152
 diff -u -p -r1.152 x86_machdep.c
 --- x86/x86/x86_machdep.c	20 Aug 2022 23:48:51 -0000	1.152
 +++ x86/x86/x86_machdep.c	23 Dec 2022 16:02:54 -0000
 @@ -870,11 +870,13 @@ x86_add_xen_clusters(void)
  			switch (map_entry[i].type) {
  			case XEN_HVM_MEMMAP_TYPE_RAM:
  				x86_add_cluster(map_entry[i].addr,
 -				    map_entry[i].size, BIM_Memory);
 +				    map_entry[i].addr + map_entry[i].size,
 +				    BIM_Memory);
  				break;
  			case XEN_HVM_MEMMAP_TYPE_ACPI:
  				x86_add_cluster(map_entry[i].addr,
 -				    map_entry[i].size, BIM_ACPI);
 +				    map_entry[i].addr + map_entry[i].size,
 +				    BIM_ACPI);
  				break;
  			}
  		}
 
 --cKygguVIx5P7Hdxx--