File 22462-x86-xsave-init-common.patch of Package xen.import4929

References: bnc#675817

# HG changeset patch
# User Keir Fraser <keir@xen.org>
# Date 1291746398 0
# Node ID 98eb4a334b7723c3e515038feaddbd01cec45a3a
# Parent  70501ee741a6dccd940c1cb4481650cdc1afdcf3
amd xsave: Move xsave initialization code to a common place

This patch moves xsave/xrstor code to CPU common file. First of all,
it prepares xsave/xrstor support for AMD CPUs. Secondly, Xen would
crash on __context_switch() without this patch on xsave-capable AMD
CPUs. The crash was due to cpu_has_xsave reports true in domain.c
while xsave space wasn't initialized.

Signed-off-by: Wei Huang <wei.huang2@amd.com>

Index: xen-4.0.2-testing/xen/arch/x86/cpu/common.c
===================================================================
--- xen-4.0.2-testing.orig/xen/arch/x86/cpu/common.c
+++ xen-4.0.2-testing/xen/arch/x86/cpu/common.c
@@ -22,6 +22,8 @@ static int cachesize_override __cpuinitd
 static int disable_x86_fxsr __cpuinitdata;
 static int disable_x86_serial_nr __cpuinitdata;
 
+static int use_xsave;
+boolean_param("xsave", use_xsave);
 unsigned int __devinitdata opt_cpuid_mask_ecx = ~0u;
 integer_param("cpuid_mask_ecx", opt_cpuid_mask_ecx);
 unsigned int __devinitdata opt_cpuid_mask_edx = ~0u;
@@ -400,6 +402,13 @@ void __cpuinit identify_cpu(struct cpuin
 	if (this_cpu->c_init)
 		this_cpu->c_init(c);
 
+        /* Initialize xsave/xrstor features */
+	if ( !use_xsave )
+		clear_bit(X86_FEATURE_XSAVE, boot_cpu_data.x86_capability);
+
+	if ( cpu_has_xsave )
+		xsave_init();
+
 	/* Disable the PN if appropriate */
 	squash_the_stupid_serial_number(c);
 
Index: xen-4.0.2-testing/xen/arch/x86/cpu/intel.c
===================================================================
--- xen-4.0.2-testing.orig/xen/arch/x86/cpu/intel.c
+++ xen-4.0.2-testing/xen/arch/x86/cpu/intel.c
@@ -20,9 +20,6 @@
 
 extern int trap_init_f00f_bug(void);
 
-static int use_xsave;
-boolean_param("xsave", use_xsave);
-
 #ifdef CONFIG_X86_INTEL_USERCOPY
 /*
  * Alignment at which movsl is preferred for bulk memory copies.
@@ -256,12 +253,6 @@ static void __devinit init_intel(struct
 		set_bit(X86_FEATURE_ARAT, c->x86_capability);
 
 	start_vmx();
-
-	if ( !use_xsave )
-		clear_bit(X86_FEATURE_XSAVE, boot_cpu_data.x86_capability);
-
-	if ( cpu_has_xsave )
-		xsave_init();
 }