Re: [PATCH 1/1] perf probe:fix sigsegv in adding nonexistent event

[Arnaldo Carvalho de Melo <acme@ghostprotocols.net>]

Em Tue, Oct 25, 2011 at 08:39:05PM -0700, furat.afram@gmail.com escreveu:
> From: Furat Afram <furat.afram@gmail.com>
> 
> pref probe crashes when trying to add nonexistent event

Can you provide a backtrace of such crash? I'm having difficulty to
figure out how the patch provided will fix perf probe.

- Arnaldo
 
> Signed-off-by: Furat Afram <furat.afram@gmail.com>
> ---
>  tools/perf/util/symbol.c |    8 ++++++--
>  1 files changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
> index 40eeaf0..ad0c79b 100644
> --- a/tools/perf/util/symbol.c
> +++ b/tools/perf/util/symbol.c
> @@ -636,14 +636,18 @@ static int dso__load_all_kallsyms(struct dso *dso, const char *filename,
>  static int dso__split_kallsyms(struct dso *dso, struct map *map,
>  			       symbol_filter_t filter)
>  {
> -	struct map_groups *kmaps = map__kmap(map)->kmaps;
> -	struct machine *machine = kmaps->machine;
> +	struct map_groups *kmaps;
> +	struct machine *machine;
>  	struct map *curr_map = map;
>  	struct symbol *pos;
>  	int count = 0, moved = 0;	
>  	struct rb_root *root = &dso->symbols[map->type];
>  	struct rb_node *next = rb_first(root);
>  	int kernel_range = 0;
> +	kmaps = map__kmap(map)->kmaps;
> +	if (kmaps == NULL)
> +		return -1;
> +	machine = kmaps->machine;
>  
>  	while (next) {
>  		char *module;
> -- 
> 1.7.6.4