1 files changed, 38 insertions, 7 deletions

diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c
index b004a1fb6032..56add6327736 100644
--- a/kernel/livepatch/transition.c
+++ b/kernel/livepatch/transition.c
@@ -82,6 +82,10 @@ static void klp_complete_transition(void)
         unsigned int cpu;
         bool immediate_func = false;
 
+        pr_debug("'%s': completing %s transition\n",
+                 klp_transition_patch->mod->name,
+                 klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
+
         if (klp_target_state == KLP_UNPATCHED) {
                 /*
                  * All tasks have transitioned to KLP_UNPATCHED so we can now
@@ -109,9 +113,6 @@ static void klp_complete_transition(void)
                 }
         }
 
-        if (klp_target_state == KLP_UNPATCHED && !immediate_func)
-                module_put(klp_transition_patch->mod);
-
         /* Prevent klp_ftrace_handler() from seeing KLP_UNDEFINED state */
         if (klp_target_state == KLP_PATCHED)
                 klp_synchronize_transition();
@@ -130,6 +131,27 @@ static void klp_complete_transition(void)
         }
 
 done:
+        klp_for_each_object(klp_transition_patch, obj) {
+                if (!klp_is_object_loaded(obj))
+                        continue;
+                if (klp_target_state == KLP_PATCHED)
+                        klp_post_patch_callback(obj);
+                else if (klp_target_state == KLP_UNPATCHED)
+                        klp_post_unpatch_callback(obj);
+        }
+
+        pr_notice("'%s': %s complete\n", klp_transition_patch->mod->name,
+                  klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
+
+        /*
+         * See complementary comment in __klp_enable_patch() for why we
+         * keep the module reference for immediate patches.
+         */
+        if (!klp_transition_patch->immediate && !immediate_func &&
+            klp_target_state == KLP_UNPATCHED) {
+                module_put(klp_transition_patch->mod);
+        }
+
         klp_target_state = KLP_UNDEFINED;
         klp_transition_patch = NULL;
 }
@@ -145,6 +167,9 @@ void klp_cancel_transition(void)
         if (WARN_ON_ONCE(klp_target_state != KLP_PATCHED))
                 return;
 
+        pr_debug("'%s': canceling patching transition, going to unpatch\n",
+                 klp_transition_patch->mod->name);
+
         klp_target_state = KLP_UNPATCHED;
         klp_complete_transition();
 }
@@ -408,9 +433,6 @@ void klp_try_complete_transition(void)
         }
 
 success:
-        pr_notice("'%s': %s complete\n", klp_transition_patch->mod->name,
-                  klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
-
         /* we're done, now cleanup the data structures */
         klp_complete_transition();
 }
@@ -426,7 +448,8 @@ void klp_start_transition(void)
 
         WARN_ON_ONCE(klp_target_state == KLP_UNDEFINED);
 
-        pr_notice("'%s': %s...\n", klp_transition_patch->mod->name,
+        pr_notice("'%s': starting %s transition\n",
+                  klp_transition_patch->mod->name,
                   klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
 
         /*
@@ -482,6 +505,9 @@ void klp_init_transition(struct klp_patch *patch, int state)
          */
         klp_target_state = state;
 
+        pr_debug("'%s': initializing %s transition\n", patch->mod->name,
+                 klp_target_state == KLP_PATCHED ? "patching" : "unpatching");
+
         /*
          * If the patch can be applied or reverted immediately, skip the
          * per-task transitions.
@@ -547,6 +573,11 @@ void klp_reverse_transition(void)
         unsigned int cpu;
         struct task_struct *g, *task;
 
+        pr_debug("'%s': reversing transition from %s\n",
+                 klp_transition_patch->mod->name,
+                 klp_target_state == KLP_PATCHED ? "patching to unpatching" :
+                                                   "unpatching to patching");
+
         klp_transition_patch->enabled = !klp_transition_patch->enabled;
 
         klp_target_state = !klp_target_state;