From 2e96e1a58dbf51e58580592ce0f32d2f1cbe39ce Mon Sep 17 00:00:00 2001
From: Jeremy Fitzhardinge <jeremy@goop.org>
Date: Mon, 26 May 2008 23:31:01 +0100
Subject: [PATCH] --- yaml --- r: 99534 b: refs/heads/master c:
 7b1333aa4cb546ddeb9c05098a53d9a777623a05 h: refs/heads/master v: v3

---
 [refs]                                |  2 +-
 trunk/arch/x86/xen/enlighten.c        | 28 +++++++++++++++++++++++++--
 trunk/include/asm-x86/xen/hypercall.h |  7 +++++++
 3 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/[refs] b/[refs]
index 10b75c872e96..e2b2592f1f04 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0922abdc3982ae54cbe1b24ac5aa91a260eca1bb
+refs/heads/master: 7b1333aa4cb546ddeb9c05098a53d9a777623a05
diff --git a/trunk/arch/x86/xen/enlighten.c b/trunk/arch/x86/xen/enlighten.c
index a05b7721bc81..446f4cd649e6 100644
--- a/trunk/arch/x86/xen/enlighten.c
+++ b/trunk/arch/x86/xen/enlighten.c
@@ -607,6 +607,30 @@ static void xen_flush_tlb_others(const cpumask_t *cpus, struct mm_struct *mm,
 	xen_mc_issue(PARAVIRT_LAZY_MMU);
 }
 
+static void xen_clts(void)
+{
+	struct multicall_space mcs;
+
+	mcs = xen_mc_entry(0);
+
+	MULTI_fpu_taskswitch(mcs.mc, 0);
+
+	xen_mc_issue(PARAVIRT_LAZY_CPU);
+}
+
+static void xen_write_cr0(unsigned long cr0)
+{
+	struct multicall_space mcs;
+
+	/* Only pay attention to cr0.TS; everything else is
+	   ignored. */
+	mcs = xen_mc_entry(0);
+
+	MULTI_fpu_taskswitch(mcs.mc, (cr0 & X86_CR0_TS) != 0);
+
+	xen_mc_issue(PARAVIRT_LAZY_CPU);
+}
+
 static void xen_write_cr2(unsigned long cr2)
 {
 	x86_read_percpu(xen_vcpu)->arch.cr2 = cr2;
@@ -978,10 +1002,10 @@ static const struct pv_cpu_ops xen_cpu_ops __initdata = {
 	.set_debugreg = xen_set_debugreg,
 	.get_debugreg = xen_get_debugreg,
 
-	.clts = native_clts,
+	.clts = xen_clts,
 
 	.read_cr0 = native_read_cr0,
-	.write_cr0 = native_write_cr0,
+	.write_cr0 = xen_write_cr0,
 
 	.read_cr4 = native_read_cr4,
 	.read_cr4_safe = native_read_cr4_safe,
diff --git a/trunk/include/asm-x86/xen/hypercall.h b/trunk/include/asm-x86/xen/hypercall.h
index c2ccd997ed35..897ff79cca3b 100644
--- a/trunk/include/asm-x86/xen/hypercall.h
+++ b/trunk/include/asm-x86/xen/hypercall.h
@@ -314,6 +314,13 @@ HYPERVISOR_nmi_op(unsigned long op, unsigned long arg)
 	return _hypercall2(int, nmi_op, op, arg);
 }
 
+static inline void
+MULTI_fpu_taskswitch(struct multicall_entry *mcl, int set)
+{
+	mcl->op = __HYPERVISOR_fpu_taskswitch;
+	mcl->args[0] = set;
+}
+
 static inline void
 MULTI_update_va_mapping(struct multicall_entry *mcl, unsigned long va,
 			pte_t new_val, unsigned long flags)