Merge branch 'stable-3.2' into pandora-3.2

[pandora-kernel.git] / kernel / trace / trace.c

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index a1b9afd..16b01c4 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1100,7 +1100,7 @@ void trace_find_cmdline(int pid, char comm[])
        arch_spin_lock(&trace_cmdline_lock);
        map = map_pid_to_cmdline[pid];
        if (map != NO_CMDLINE_MAP)
-               strcpy(comm, saved_cmdlines[map]);
+               strlcpy(comm, saved_cmdlines[map], TASK_COMM_LEN);
        else
                strcpy(comm, "<...>");
 
@@ -3331,13 +3331,6 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
        static struct tracer *old_tracer;
        ssize_t sret;
 
-       /* return any leftover data */
-       sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
-       if (sret != -EBUSY)
-               return sret;
-
-       trace_seq_init(&iter->seq);
-
        /* copy the tracer to avoid using a global lock all around */
        mutex_lock(&trace_types_lock);
        if (unlikely(old_tracer != current_trace && current_trace)) {
@@ -3352,6 +3345,14 @@ tracing_read_pipe(struct file *filp, char __user *ubuf,
         * is protected.
         */
        mutex_lock(&iter->mutex);
+
+       /* return any leftover data */
+       sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
+       if (sret != -EBUSY)
+               goto out;
+
+       trace_seq_init(&iter->seq);
+
        if (iter->trace->read) {
                sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
                if (sret)
@@ -3565,7 +3566,10 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
 
        spd.nr_pages = i;
 
-       ret = splice_to_pipe(pipe, &spd);
+       if (i)
+               ret = splice_to_pipe(pipe, &spd);
+       else
+               ret = 0;
 out:
        splice_shrink_spd(&spd);
        return ret;