5 files changed, 50 insertions, 31 deletions

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index 479d4d5672f9..5016bfb682b9 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -919,10 +919,8 @@ static int __kprobes pre_handler_kretprobe(struct kprobe *p,
                 ri->rp = rp;
                 ri->task = current;
 
-                if (rp->entry_handler && rp->entry_handler(ri, regs)) {
-                        spin_unlock_irqrestore(&rp->lock, flags);
+                if (rp->entry_handler && rp->entry_handler(ri, regs))
                         return 0;
-                }
 
                 arch_prepare_kretprobe(ri, regs);
 
diff --git a/kernel/module.c b/kernel/module.c
index 8b742f2b3845..7fa134e0cc24 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2049,14 +2049,6 @@ static noinline struct module *load_module(void __user *umod,
         if (err < 0)
                 goto free_mod;
 
-#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
-        mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t),
-                                      mod->name);
-        if (!mod->refptr) {
-                err = -ENOMEM;
-                goto free_mod;
-        }
-#endif
         if (pcpuindex) {
                 /* We have a special allocation for this section. */
                 percpu = percpu_modalloc(sechdrs[pcpuindex].sh_size,
@@ -2064,7 +2056,7 @@ static noinline struct module *load_module(void __user *umod,
                                          mod->name);
                 if (!percpu) {
                         err = -ENOMEM;
-                        goto free_percpu;
+                        goto free_mod;
                 }
                 sechdrs[pcpuindex].sh_flags &= ~(unsigned long)SHF_ALLOC;
                 mod->percpu = percpu;
@@ -2116,6 +2108,14 @@ static noinline struct module *load_module(void __user *umod,
         /* Module has been moved. */
         mod = (void *)sechdrs[modindex].sh_addr;
 
+#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
+        mod->refptr = percpu_modalloc(sizeof(local_t), __alignof__(local_t),
+                                      mod->name);
+        if (!mod->refptr) {
+                err = -ENOMEM;
+                goto free_init;
+        }
+#endif
         /* Now we've moved module, initialize linked lists, etc. */
         module_unload_init(mod);
 
@@ -2322,15 +2322,17 @@ static noinline struct module *load_module(void __user *umod,
         ftrace_release(mod->module_core, mod->core_size);
  free_unload:
         module_unload_free(mod);
+ free_init:
+#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
+        percpu_modfree(mod->refptr);
+#endif
         module_free(mod, mod->module_init);
  free_core:
         module_free(mod, mod->module_core);
+        /* mod will be freed with core. Don't access it beyond this line! */
  free_percpu:
         if (percpu)
                 percpu_modfree(percpu);
-#if defined(CONFIG_MODULE_UNLOAD) && defined(CONFIG_SMP)
-        percpu_modfree(mod->refptr);
-#endif
  free_mod:
         kfree(args);
  free_hdr:
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index bbf51922a8ca..384ca5d9d729 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -577,8 +577,17 @@ struct ring_buffer *ring_buffer_alloc(unsigned long size, unsigned flags)
         if (buffer->pages == 1)
                 buffer->pages++;
 
+        /*
+         * In case of non-hotplug cpu, if the ring-buffer is allocated
+         * in early initcall, it will not be notified of secondary cpus.
+         * In that off case, we need to allocate for all possible cpus.
+         */
+#ifdef CONFIG_HOTPLUG_CPU
         get_online_cpus();
         cpumask_copy(buffer->cpumask, cpu_online_mask);
+#else
+        cpumask_copy(buffer->cpumask, cpu_possible_mask);
+#endif
         buffer->cpus = nr_cpu_ids;
 
         bsize = sizeof(void *) * nr_cpu_ids;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index f7f359d45823..e3dfefe69348 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -641,6 +641,7 @@ void tracing_reset_online_cpus(struct trace_array *tr)
 }
 
 #define SAVED_CMDLINES 128
+#define NO_CMDLINE_MAP UINT_MAX
 static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
 static unsigned map_cmdline_to_pid[SAVED_CMDLINES];
 static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN];
@@ -652,8 +653,8 @@ static atomic_t trace_record_cmdline_disabled __read_mostly;
 
 static void trace_init_cmdlines(void)
 {
-        memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline));
-        memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid));
+        memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline));
+        memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid));
         cmdline_idx = 0;
 }
 
@@ -745,8 +746,7 @@ void trace_stop_cmdline_recording(void);
 
 static void trace_save_cmdline(struct task_struct *tsk)
 {
-        unsigned map;
-        unsigned idx;
+        unsigned pid, idx;
 
         if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT))
                 return;
@@ -761,13 +761,20 @@ static void trace_save_cmdline(struct task_struct *tsk)
                 return;
 
         idx = map_pid_to_cmdline[tsk->pid];
-        if (idx >= SAVED_CMDLINES) {
+        if (idx == NO_CMDLINE_MAP) {
                 idx = (cmdline_idx + 1) % SAVED_CMDLINES;
 
-                map = map_cmdline_to_pid[idx];
-                if (map <= PID_MAX_DEFAULT)
-                        map_pid_to_cmdline[map] = (unsigned)-1;
+                /*
+                 * Check whether the cmdline buffer at idx has a pid
+                 * mapped. We are going to overwrite that entry so we
+                 * need to clear the map_pid_to_cmdline. Otherwise we
+                 * would read the new comm for the old pid.
+                 */
+                pid = map_cmdline_to_pid[idx];
+                if (pid != NO_CMDLINE_MAP)
+                        map_pid_to_cmdline[pid] = NO_CMDLINE_MAP;
 
+                map_cmdline_to_pid[idx] = tsk->pid;
                 map_pid_to_cmdline[tsk->pid] = idx;
 
                 cmdline_idx = idx;
@@ -794,18 +801,18 @@ void trace_find_cmdline(int pid, char comm[])
 
         __raw_spin_lock(&trace_cmdline_lock);
         map = map_pid_to_cmdline[pid];
-        if (map >= SAVED_CMDLINES)
-                goto out;
-
-        strcpy(comm, saved_cmdlines[map]);
+        if (map != NO_CMDLINE_MAP)
+                strcpy(comm, saved_cmdlines[map]);
+        else
+                strcpy(comm, "<...>");
 
- out:
         __raw_spin_unlock(&trace_cmdline_lock);
 }
 
 void tracing_record_cmdline(struct task_struct *tsk)
 {
-        if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on())
+        if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled ||
+            !tracing_is_on())
                 return;
 
         trace_save_cmdline(tsk);
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 79602740bbb5..1ef5d3a601c7 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -272,12 +272,15 @@ static void disable_tracepoint(struct tracepoint *elem)
  *
  * Updates the probe callback corresponding to a range of tracepoints.
  */
-void tracepoint_update_probe_range(struct tracepoint *begin,
-        struct tracepoint *end)
+void
+tracepoint_update_probe_range(struct tracepoint *begin, struct tracepoint *end)
 {
         struct tracepoint *iter;
         struct tracepoint_entry *mark_entry;
 
+        if (!begin)
+                return;
+
         mutex_lock(&tracepoints_mutex);
         for (iter = begin; iter < end; iter++) {
                 mark_entry = get_tracepoint(iter->name);