Merge commit 'v2.6.27-rc7' into x86/pebs

[pandora-kernel.git] / arch / x86 / kernel / process_32.c

diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c
index 3b7a1dd..ae584f8 100644 (file)
--- a/arch/x86/kernel/process_32.c
+++ b/arch/x86/kernel/process_32.c
@@ -275,6 +275,14 @@ void exit_thread(void)
                tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;
                put_cpu();
        }
+#ifdef CONFIG_X86_DS
+       /* Free any DS contexts that have not been properly released. */
+       if (unlikely(current->thread.ds_ctx)) {
+               /* we clear debugctl to make sure DS is not used. */
+               update_debugctlmsr(0);
+               ds_free(current->thread.ds_ctx);
+       }
+#endif /* CONFIG_X86_DS */
 }
 
 void flush_thread(void)
@@ -436,6 +444,35 @@ int set_tsc_mode(unsigned int val)
        return 0;
 }
 
+#ifdef CONFIG_X86_DS
+static int update_debugctl(struct thread_struct *prev,
+                       struct thread_struct *next, unsigned long debugctl)
+{
+       unsigned long ds_prev = 0;
+       unsigned long ds_next = 0;
+
+       if (prev->ds_ctx)
+               ds_prev = (unsigned long)prev->ds_ctx->ds;
+       if (next->ds_ctx)
+               ds_next = (unsigned long)next->ds_ctx->ds;
+
+       if (ds_next != ds_prev) {
+               /* we clear debugctl to make sure DS
+                * is not in use when we change it */
+               debugctl = 0;
+               update_debugctlmsr(0);
+               wrmsr(MSR_IA32_DS_AREA, ds_next, 0);
+       }
+       return debugctl;
+}
+#else
+static int update_debugctl(struct thread_struct *prev,
+                       struct thread_struct *next, unsigned long debugctl)
+{
+       return debugctl;
+}
+#endif /* CONFIG_X86_DS */
+
 static noinline void
 __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
                 struct tss_struct *tss)
@@ -446,14 +483,7 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
        prev = &prev_p->thread;
        next = &next_p->thread;
 
-       debugctl = prev->debugctlmsr;
-       if (next->ds_area_msr != prev->ds_area_msr) {
-               /* we clear debugctl to make sure DS
-                * is not in use when we change it */
-               debugctl = 0;
-               update_debugctlmsr(0);
-               wrmsr(MSR_IA32_DS_AREA, next->ds_area_msr, 0);
-       }
+       debugctl = update_debugctl(prev, next, prev->debugctlmsr);
 
        if (next->debugctlmsr != debugctl)
                update_debugctlmsr(next->debugctlmsr);
@@ -477,13 +507,13 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
                        hard_enable_TSC();
        }
 
-#ifdef X86_BTS
+#ifdef CONFIG_X86_PTRACE_BTS
        if (test_tsk_thread_flag(prev_p, TIF_BTS_TRACE_TS))
                ptrace_bts_take_timestamp(prev_p, BTS_TASK_DEPARTS);
 
        if (test_tsk_thread_flag(next_p, TIF_BTS_TRACE_TS))
                ptrace_bts_take_timestamp(next_p, BTS_TASK_ARRIVES);
-#endif
+#endif /* CONFIG_X86_PTRACE_BTS */
 
 
        if (!test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {