x86, ds: add leakage warning

Add a warning in case a debug store context is not removed before
the task it is attached to is freed.

Remove the old warning at thread exit. It is too early.

Declare the debug store context field in thread_struct unconditionally.

Remove ds_copy_thread() and ds_exit_thread() and do the work directly
in process*.c.

Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Cc: roland@redhat.com
Cc: eranian@googlemail.com
Cc: oleg@redhat.com
Cc: juan.villacis@intel.com
Cc: ak@linux.jf.intel.com
LKML-Reference: <20090403144601.254472000@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 2 insertions, 1 deletions

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index b751a41392b1..5a1a1de292ec 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -335,7 +335,8 @@ int copy_thread(unsigned long clone_flags, unsigned long sp,
                         goto out;
         }
 
-        ds_copy_thread(p, me);
+        clear_tsk_thread_flag(p, TIF_DS_AREA_MSR);
+        p->thread.ds_ctx = NULL;
 
         clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR);
         p->thread.debugctlmsr = 0;