tracing: Fix checking event hash pointer logic when tp_printk is enabled

[sfrench/cifs-2.6.git] / kernel / trace / trace.c

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c777627212fa81cc3dc4fd70cbba807c62a5acc..c0c9aa5cd8e2c1fd1786d07635a1bc9d11373a32 100644 (file)
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3545,7 +3545,11 @@ static char *trace_iter_expand_format(struct trace_iterator *iter)
 {
        char *tmp;
 
-       if (iter->fmt == static_fmt_buf)
+       /*
+        * iter->tr is NULL when used with tp_printk, which makes
+        * this get called where it is not safe to call krealloc().
+        */
+       if (!iter->tr || iter->fmt == static_fmt_buf)
                return NULL;
 
        tmp = krealloc(iter->fmt, iter->fmt_size + STATIC_FMT_BUF_SIZE,
@@ -3566,7 +3570,7 @@ const char *trace_event_format(struct trace_iterator *iter, const char *fmt)
        if (WARN_ON_ONCE(!fmt))
                return fmt;
 
-       if (iter->tr->trace_flags & TRACE_ITER_HASH_PTR)
+       if (!iter->tr || iter->tr->trace_flags & TRACE_ITER_HASH_PTR)
                return fmt;
 
        p = fmt;
@@ -9692,7 +9696,7 @@ void __init early_trace_init(void)
 {
        if (tracepoint_printk) {
                tracepoint_print_iter =
-                       kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL);
+                       kzalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL);
                if (MEM_FAIL(!tracepoint_print_iter,
                             "Failed to allocate trace iterator\n"))
                        tracepoint_printk = 0;