From 8737a1de13192ec1838186af7d547beefba098f4 Mon Sep 17 00:00:00 2001
From: Jeremy Fitzhardinge <jeremy@goop.org>
Date: Tue, 8 Jul 2008 15:07:16 -0700
Subject: [PATCH] --- yaml --- r: 104448 b: refs/heads/master c:
 1153968a48e3ca3e2b7a437e8b82ec9e6f768e24 h: refs/heads/master v: v3

---
 [refs]                         |  2 +-
 trunk/arch/x86/xen/enlighten.c | 31 ++++++++++++++++++++++++++++++-
 2 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/[refs] b/[refs]
index bacd93a046fe..27df0b34a838 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: bf18bf94dc72db998d0fbebc846c07c858a59c90
+refs/heads/master: 1153968a48e3ca3e2b7a437e8b82ec9e6f768e24
diff --git a/trunk/arch/x86/xen/enlighten.c b/trunk/arch/x86/xen/enlighten.c
index f64b8729cd07..776c0fb77d69 100644
--- a/trunk/arch/x86/xen/enlighten.c
+++ b/trunk/arch/x86/xen/enlighten.c
@@ -41,6 +41,7 @@
 #include <asm/xen/hypervisor.h>
 #include <asm/fixmap.h>
 #include <asm/processor.h>
+#include <asm/msr-index.h>
 #include <asm/setup.h>
 #include <asm/desc.h>
 #include <asm/pgtable.h>
@@ -777,6 +778,34 @@ static void xen_write_cr3(unsigned long cr3)
 	xen_mc_issue(PARAVIRT_LAZY_CPU);  /* interrupts restored */
 }
 
+static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
+{
+	int ret;
+
+	ret = 0;
+
+	switch(msr) {
+#ifdef CONFIG_X86_64
+		unsigned which;
+		u64 base;
+
+	case MSR_FS_BASE:		which = SEGBASE_FS; goto set;
+	case MSR_KERNEL_GS_BASE:	which = SEGBASE_GS_USER; goto set;
+	case MSR_GS_BASE:		which = SEGBASE_GS_KERNEL; goto set;
+
+	set:
+		base = ((u64)high << 32) | low;
+		if (HYPERVISOR_set_segment_base(which, base) != 0)
+			ret = -EFAULT;
+		break;
+#endif
+	default:
+		ret = native_write_msr_safe(msr, low, high);
+	}
+
+	return ret;
+}
+
 /* Early in boot, while setting up the initial pagetable, assume
    everything is pinned. */
 static __init void xen_alloc_pte_init(struct mm_struct *mm, u32 pfn)
@@ -1165,7 +1194,7 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = {
 	.wbinvd = native_wbinvd,
 
 	.read_msr = native_read_msr_safe,
-	.write_msr = native_write_msr_safe,
+	.write_msr = xen_write_msr_safe,
 	.read_tsc = native_read_tsc,
 	.read_pmc = native_read_pmc,