Merge branch 'master' of git://sources.redhat.com/git/systemtap

1 files changed, 35 insertions, 8 deletions

diff --git a/runtime/uprobes2/uprobes.c b/runtime/uprobes2/uprobes.c
index a0e9f2fe..9ea05349 100644
--- a/runtime/uprobes2/uprobes.c
+++ b/runtime/uprobes2/uprobes.c
@@ -955,10 +955,15 @@ static int defer_registration(struct uprobe *u, int regflag,
  */
 static struct pid *uprobe_get_tg_leader(pid_t p)
 {
-	struct pid *pid;
+	struct pid *pid = NULL;
 
 	rcu_read_lock();
-	pid = find_vpid(p);
+	/*
+	 * We need this check because unmap_u[ret]probe() can be called
+	 * from a report_death callback, where current->proxy is NULL.
+	 */
+	if (current->nsproxy)
+		pid = find_vpid(p);
 	if (pid) {
 		struct task_struct *t = pid_task(pid, PIDTYPE_PID);
 		if (t)
@@ -1138,8 +1143,7 @@ fail_tsk:
 }
 EXPORT_SYMBOL_GPL(register_uprobe);
 
-/* See Documentation/uprobes.txt. */
-void unregister_uprobe(struct uprobe *u)
+void __unregister_uprobe(struct uprobe *u, bool remove_bkpt)
 {
 	struct pid *p;
 	struct uprobe_process *uproc;
@@ -1193,10 +1197,13 @@ void unregister_uprobe(struct uprobe *u)
 	if (!list_empty(&ppt->uprobe_list))
 		goto done;
 
-	/*
-	 * The last uprobe at ppt's probepoint is being unregistered.
-	 * Queue the breakpoint for removal.
-	 */
+	/* The last uprobe at ppt's probepoint is being unregistered. */
+	if (!remove_bkpt) {
+		uprobe_free_probept(ppt);
+		goto done;
+	}
+
+	/* Queue the breakpoint for removal. */
 	ppt->state = UPROBE_REMOVING;
 	list_add_tail(&ppt->pd_node, &uproc->pending_uprobes);
 
@@ -1221,8 +1228,20 @@ done:
 	up_write(&uproc->rwsem);
 	uprobe_put_process(uproc, false);
 }
+
+/* See Documentation/uprobes.txt. */
+void unregister_uprobe(struct uprobe *u)
+{
+	__unregister_uprobe(u, true);
+}
 EXPORT_SYMBOL_GPL(unregister_uprobe);
 
+void unmap_uprobe(struct uprobe *u)
+{
+	__unregister_uprobe(u, false);
+}
+EXPORT_SYMBOL_GPL(unmap_uprobe);
+
 /* Find a surviving thread in uproc.  Runs with uproc->rwsem locked. */
 static struct task_struct *find_surviving_thread(struct uprobe_process *uproc)
 {
@@ -2718,6 +2737,14 @@ void unregister_uretprobe(struct uretprobe *rp)
 }
 EXPORT_SYMBOL_GPL(unregister_uretprobe);
 
+void unmap_uretprobe(struct uretprobe *rp)
+{
+	if (!rp)
+		return;
+	unmap_uprobe(&rp->u);
+}
+EXPORT_SYMBOL_GPL(unmap_uretprobe);
+
 /*
  * uproc->ssol_area has been successfully set up.  Establish the
  * uretprobe trampoline in the next available slot following the