linux-kernel - [PATCH 06/10] xen/setup: Only set identity mapping in E820 regions when privileged.

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Date:	Tue, 21 Dec 2010 16:37:36 -0500
From:	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
To:	linux-kernel@...r.kernel.org, jeremy@...p.org, hpa@...or.com
Cc:	Jan Beulich <JBeulich@...ell.com>, xen-devel@...ts.xensource.com,
	Konrad Rzeszutek Wilk <konrad@...nel.org>,
	Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
Subject: [PATCH 06/10] xen/setup: Only set identity mapping in E820 regions when privileged.

We do not want to set the identity mapping on E820 reserved
regions when running as PV. This is b/c the 0->ISA_END_ADDRESS region
would be considered identity and we would try to read DMI information
and fail (since the pfn_to_mfn(mfn)==pfn) under PV guests.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@...cle.com>
---
 arch/x86/xen/setup.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 752c865..34fb906 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -160,7 +160,7 @@ static unsigned long __init xen_set_identity(const struct e820map *e820)
 		if (end < start)
 			continue;
 
-		if (e820->map[i].type != E820_RAM) {
+		if (xen_initial_domain() && e820->map[i].type != E820_RAM) {
 			for (pfn = PFN_UP(start); pfn < PFN_DOWN(end); pfn++)
 				set_phys_to_machine(pfn, pfn);
 			identity += pfn - PFN_UP(start);
-- 
1.7.1

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