From: Ian Campbell <ian.campbell@citrix.com>
Date: Fri, 3 Dec 2010 09:54:03 +0000 (+0000)
Subject: xen: disable ACPI NUMA for PV guests
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=c1f5db1a53a7286f6c818f71016ae6aced814d27;p=openwrt%2Fstaging%2Fblogic.git

xen: disable ACPI NUMA for PV guests

Xen does not currently expose PV-NUMA information to PV
guests. Therefore disable NUMA for the time being to prevent the
kernel picking up on an host-level NUMA information which it might
come across in the firmware.

[ Added comment - Jeremy ]

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index 44dcad43989d..ed47d12fdecb 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1174,6 +1174,15 @@ asmlinkage void __init xen_start_kernel(void)
 
 	xen_smp_init();
 
+#ifdef CONFIG_ACPI_NUMA
+	/*
+	 * The pages we from Xen are not related to machine pages, so
+	 * any NUMA information the kernel tries to get from ACPI will
+	 * be meaningless.  Prevent it from trying.
+	 */
+	acpi_numa = -1;
+#endif
+
 	pgd = (pgd_t *)xen_start_info->pt_base;
 
 	if (!xen_initial_domain())