1 files changed, 16 insertions, 24 deletions

diff --git a/linux-2.6-xen-sparse/arch/x86_64/kernel/process-xen.c b/linux-2.6-xen-sparse/arch/x86_64/kernel/process-xen.c
index 8267a772b7..c1642b033a 100644
--- a/linux-2.6-xen-sparse/arch/x86_64/kernel/process-xen.c
+++ b/linux-2.6-xen-sparse/arch/x86_64/kernel/process-xen.c
@@ -38,8 +38,8 @@
 #include <linux/ptrace.h>
 #include <linux/utsname.h>
 #include <linux/random.h>
-#include <linux/kprobes.h>
 #include <linux/notifier.h>
+#include <linux/kprobes.h>
 
 #include <asm/uaccess.h>
 #include <asm/pgtable.h>
@@ -75,24 +75,17 @@ EXPORT_SYMBOL(boot_option_idle_override);
 void (*pm_idle)(void);
 static DEFINE_PER_CPU(unsigned int, cpu_idle_state);
 
-static struct notifier_block *idle_notifier;
-static DEFINE_SPINLOCK(idle_notifier_lock);
+static ATOMIC_NOTIFIER_HEAD(idle_notifier);
 
 void idle_notifier_register(struct notifier_block *n)
 {
-	unsigned long flags;
-	spin_lock_irqsave(&idle_notifier_lock, flags);
-	notifier_chain_register(&idle_notifier, n);
-	spin_unlock_irqrestore(&idle_notifier_lock, flags);
+	atomic_notifier_chain_register(&idle_notifier, n);
 }
 EXPORT_SYMBOL_GPL(idle_notifier_register);
 
 void idle_notifier_unregister(struct notifier_block *n)
 {
-	unsigned long flags;
-	spin_lock_irqsave(&idle_notifier_lock, flags);
-	notifier_chain_unregister(&idle_notifier, n);
-	spin_unlock_irqrestore(&idle_notifier_lock, flags);
+	atomic_notifier_chain_unregister(&idle_notifier, n);
 }
 EXPORT_SYMBOL(idle_notifier_unregister);
 
@@ -102,13 +95,13 @@ static DEFINE_PER_CPU(enum idle_state, idle_state) = CPU_NOT_IDLE;
 void enter_idle(void)
 {
 	__get_cpu_var(idle_state) = CPU_IDLE;
-	notifier_call_chain(&idle_notifier, IDLE_START, NULL);
+	atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
 }
 
 static void __exit_idle(void)
 {
 	__get_cpu_var(idle_state) = CPU_NOT_IDLE;
-	notifier_call_chain(&idle_notifier, IDLE_END, NULL);
+	atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
 }
 
 /* Called from interrupts to signify idle end */
@@ -309,13 +302,6 @@ void exit_thread(void)
 	struct task_struct *me = current;
 	struct thread_struct *t = &me->thread;
 
-	/*
-	 * Remove function-return probe instances associated with this task
-	 * and put them back on the free list. Do not insert an exit probe for
-	 * this function, it will be disabled by kprobe_flush_task if you do.
-	 */
-	kprobe_flush_task(me);
-
 	if (me->thread.io_bitmap_ptr) { 
 #ifndef CONFIG_X86_NO_TSS
 		struct tss_struct *tss = &per_cpu(init_tss, get_cpu());
@@ -512,7 +498,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 	 * multicall to indicate FPU task switch, rather than
 	 * synchronously trapping to Xen.
 	 * This must be here to ensure both math_state_restore() and
-	 * kernel_fpu_begin() work consistently.
+	 * kernel_fpu_begin() work consistently. 
 	 * The AMD workaround requires it to be after DS reload, or
 	 * after DS has been cleared, which we do in __prepare_arch_switch.
 	 */
@@ -591,7 +577,7 @@ __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
 		HYPERVISOR_set_segment_base(SEGBASE_GS_USER, next->gs); 
 
 	/* 
-	 * Switch the PDA context.
+	 * Switch the PDA and FPU contexts.
 	 */
 	prev->userrsp = read_pda(oldrsp); 
 	write_pda(oldrsp, next->userrsp); 
@@ -781,10 +767,16 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 	}
 	case ARCH_GET_GS: { 
 		unsigned long base;
+		unsigned gsindex;
 		if (task->thread.gsindex == GS_TLS_SEL)
 			base = read_32bit_tls(task, GS_TLS);
-		else if (doit)
-			rdmsrl(MSR_KERNEL_GS_BASE, base);
+		else if (doit) {
+ 			asm("movl %%gs,%0" : "=r" (gsindex));
+			if (gsindex)
+				rdmsrl(MSR_KERNEL_GS_BASE, base);
+			else
+				base = task->thread.gs;
+		}
 		else
 			base = task->thread.gs;
 		ret = put_user(base, (unsigned long __user *)addr);