Merge git://git.infradead.org/iommu-2.6

[linux-2.6-omap-h63xx.git] / arch / x86 / kernel / ptrace.c

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 0a5df5f82fb9579b1be4e824aa499ac561d9ba10..5a4c23d898926149e65b8cb5d826b7e868f4a527 100644 (file)
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -810,12 +810,16 @@ static void ptrace_bts_untrace(struct task_struct *child)
 
 static void ptrace_bts_detach(struct task_struct *child)
 {
-       if (unlikely(child->bts)) {
-               ds_release_bts(child->bts);
-               child->bts = NULL;
-
-               ptrace_bts_free_buffer(child);
-       }
+       /*
+        * Ptrace_detach() races with ptrace_untrace() in case
+        * the child dies and is reaped by another thread.
+        *
+        * We only do the memory accounting at this point and
+        * leave the buffer deallocation and the bts tracer
+        * release to ptrace_bts_untrace() which will be called
+        * later on with tasklist_lock held.
+        */
+       release_locked_buffer(child->bts_buffer, child->bts_size);
 }
 #else
 static inline void ptrace_bts_fork(struct task_struct *tsk) {}