Merge branch 'master' into pr6866

Conflicts:
	ChangeLog: Removed
	runtime/ChangeLog: Removed
	runtime/sym.c: Merged
	runtime/task_finder.c: Merged
	tapset/ChangeLog: Removed
	testsuite/ChangeLog: Removed

1 files changed, 30 insertions, 7 deletions

diff --git a/runtime/task_finder.c b/runtime/task_finder.c
index 31bccad8..ae381a41 100644
--- a/runtime/task_finder.c
+++ b/runtime/task_finder.c
@@ -22,14 +22,14 @@ struct stap_task_finder_target;
 #define __STP_TF_RUNNING	1
 #define __STP_TF_STOPPING	2
 #define __STP_TF_STOPPED	3
-atomic_t __stp_task_finder_state = ATOMIC_INIT(__STP_TF_STARTING);
-atomic_t __stp_inuse_count = ATOMIC_INIT (0);
+static atomic_t __stp_task_finder_state = ATOMIC_INIT(__STP_TF_STARTING);
+static atomic_t __stp_inuse_count = ATOMIC_INIT (0);
 
 #define __stp_tf_handler_start() (atomic_inc(&__stp_inuse_count))
 #define __stp_tf_handler_end() (atomic_dec(&__stp_inuse_count))
 
 #ifdef DEBUG_TASK_FINDER
-atomic_t __stp_attach_count = ATOMIC_INIT (0);
+static atomic_t __stp_attach_count = ATOMIC_INIT (0);
 
 #define debug_task_finder_attach() (atomic_inc(&__stp_attach_count))
 #define debug_task_finder_detach() (atomic_dec(&__stp_attach_count))
@@ -55,7 +55,7 @@ typedef int (*stap_task_finder_vm_callback)(struct stap_task_finder_target *tgt,
 					    unsigned long vm_end,
 					    unsigned long vm_pgoff);
 
-int __stp_tf_vm_cb(struct stap_task_finder_target *tgt,
+static int __stp_tf_vm_cb(struct stap_task_finder_target *tgt,
 		   struct task_struct *tsk,
 		   int map_p, char *vm_path,
 		   unsigned long vm_start,
@@ -230,6 +230,14 @@ stap_utrace_detach(struct task_struct *tsk,
 	if (tsk == NULL || tsk->pid <= 1)
 		return 0;
 
+#ifdef PF_KTHREAD
+	// Ignore kernel threads.  On systems without PF_KTHREAD,
+	// we're ok, since kernel threads won't be matched by the
+	// utrace_attach_task() call below.
+	if (tsk->flags & PF_KTHREAD)
+		return 0;
+#endif
+
 	// Notice we're not calling get_task_mm() here.  Normally we
 	// avoid tasks with no mm, because those are kernel threads.
 	// So, why is this function different?  When a thread is in
@@ -302,6 +310,14 @@ stap_utrace_detach_ops(struct utrace_engine_ops *ops)
 
 	rcu_read_lock();
 	do_each_thread(grp, tsk) {
+#ifdef PF_KTHREAD
+		// Ignore kernel threads.  On systems without
+		// PF_KTHREAD, we're ok, since kernel threads won't be
+		// matched by the stap_utrace_detach() call.
+		if (tsk->flags & PF_KTHREAD)
+			continue;
+#endif
+
 		rc = stap_utrace_detach(tsk, ops);
 		if (rc != 0)
 			goto udo_err;
@@ -414,7 +430,14 @@ __stp_utrace_attach(struct task_struct *tsk,
 	if (tsk == NULL || tsk->pid <= 1)
 		return EPERM;
 
-	// Ignore threads with no mm (which are kernel threads).
+#ifdef PF_KTHREAD
+	// Ignore kernel threads
+	if (tsk->flags & PF_KTHREAD)
+		return EPERM;
+#endif
+
+	// Ignore threads with no mm (which are either kernel threads
+	// or "mortally wounded" threads).
 	mm = get_task_mm(tsk);
 	if (! mm)
 		return EPERM;
@@ -917,7 +940,7 @@ utftq_out:
 }
 
 
-struct vm_area_struct *
+static struct vm_area_struct *
 __stp_find_file_based_vma(struct mm_struct *mm, unsigned long addr)
 {
 	struct vm_area_struct *vma = find_vma(mm, addr);
@@ -1218,7 +1241,7 @@ struct utrace_engine_ops __stp_utrace_task_finder_ops = {
 	.report_death = stap_utrace_task_finder_report_death,
 };
 
-int
+static int
 stap_start_task_finder(void)
 {
 	int rc = 0;