On Thu, Aug 20, 2015 at 11:16:32AM -0400, Dean Nelson wrote:
> Running the following perf-stat command on an arm64 system produces the
> following result...
>
> [root@aarch64 ~]# perf stat -e kmem:mm_page_alloc -a sleep 1
> Warning: [kmem:mm_page_alloc] function sizeof not defined
> Warning: Error: expected type 4 but read 0
> Segmentation fault
> [root@aarch64 ~]#
>
> The second warning message and SIGSEGV stem from the issue expressed in the
> first warning message, and are the result of ignoring the EVENT_ERROR type
> returned back through the call chain.
>
> Dealing with the first warning message is beyond the scope of this patch. But
> the second warning is addressed by this patch's first hunk. And the SIGSEGV is
> eliminated by its second hunk.
>
> Signed-off-by: Dean Nelson <dnel...@redhat.com>
Acked-by: Namhyung Kim <namhy...@kernel.org>
Thank you for fixing this!
Namhyung
> ---
> Changes in v3:
> - The desire was that a goto be used, not what I'd done in v2.
>
> Changes in v2:
> - Moved the second hunk's check for EVENT_ERROR to a separate line.
>
> tools/lib/traceevent/event-parse.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> diff --git a/tools/lib/traceevent/event-parse.c
> b/tools/lib/traceevent/event-parse.c
> index cc25f05..ed765a9 100644
> --- a/tools/lib/traceevent/event-parse.c
> +++ b/tools/lib/traceevent/event-parse.c
> @@ -1680,6 +1680,9 @@ process_cond(struct event_format *event, struct
> print_arg *top, char **tok)
> type = process_arg(event, left, &token);
>
> again:
> + if (type == EVENT_ERROR)
> + goto out_free;
> +
> /* Handle other operations in the arguments */
> if (type == EVENT_OP && strcmp(token, ":") != 0) {
> type = process_op(event, left, &token);
> @@ -1939,6 +1942,12 @@ process_op(struct event_format *event, struct
> print_arg *arg, char **tok)
> goto out_warn_free;
>
> type = process_arg_token(event, right, tok, type);
> + if (type == EVENT_ERROR) {
> + free_arg(right);
> + /* token was freed in process_arg_token() via *tok */
> + token = NULL;
> + goto out_free;
> + }
>
> if (right->type == PRINT_OP &&
> get_op_prio(arg->op.op) < get_op_prio(right->op.op)) {
--
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