On 3 May 2018 at 09:18, Leo Yan <[email protected]> wrote: > CoreSight doesn't allocate thread structure for unknown_thread in etm > auxtrace, so unknown_thread is NULL pointer. If the perf data doesn't > contain valid tid and then cs_etm__mem_access() uses unknown_thread > instead as thread handler, this results in segmentation fault when > thread__find_addr_map() accesses thread handler. > > This commit creates new thread data which is used by unknown_thread, so > CoreSight tracing can roll back to use unknown_thread if perf data > doesn't include valid thread info. This commit also releases thread > data for initialization failure case and for normal auxtrace free flow. > > Signed-off-by: Leo Yan <[email protected]> > --- > tools/perf/util/cs-etm.c | 25 +++++++++++++++++++++++-- > 1 file changed, 23 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c > index 6533b1a..417302c 100644 > --- a/tools/perf/util/cs-etm.c > +++ b/tools/perf/util/cs-etm.c > @@ -239,6 +239,7 @@ static void cs_etm__free(struct perf_session *session) > for (i = 0; i < aux->num_cpu; i++) > zfree(&aux->metadata[i]); > > + thread__zput(aux->unknown_thread); > zfree(&aux->metadata); > zfree(&aux); > } > @@ -266,6 +267,7 @@ static u32 cs_etm__mem_access(struct cs_etm_queue *etmq, > u64 address, > if (!thread) { > if (cpumode != PERF_RECORD_MISC_KERNEL) > return -EINVAL; > +
Extra line, please remove. With this change: Acked-by: Mathieu Poirier <[email protected]> > thread = etmq->etm->unknown_thread; > } > > @@ -1355,6 +1357,23 @@ int cs_etm__process_auxtrace_info(union perf_event > *event, > etm->auxtrace.free = cs_etm__free; > session->auxtrace = &etm->auxtrace; > > + etm->unknown_thread = thread__new(999999999, 999999999); > + if (!etm->unknown_thread) > + goto err_free_queues; > + > + /* > + * Initialize list node so that at thread__zput() we can avoid > + * segmentation fault at list_del_init(). > + */ > + INIT_LIST_HEAD(&etm->unknown_thread->node); > + > + err = thread__set_comm(etm->unknown_thread, "unknown", 0); > + if (err) > + goto err_delete_thread; > + > + if (thread__init_map_groups(etm->unknown_thread, etm->machine)) > + goto err_delete_thread; > + > if (dump_trace) { > cs_etm__print_auxtrace_info(auxtrace_info->priv, num_cpu); > return 0; > @@ -1369,16 +1388,18 @@ int cs_etm__process_auxtrace_info(union perf_event > *event, > > err = cs_etm__synth_events(etm, session); > if (err) > - goto err_free_queues; > + goto err_delete_thread; > > err = auxtrace_queues__process_index(&etm->queues, session); > if (err) > - goto err_free_queues; > + goto err_delete_thread; > > etm->data_queued = etm->queues.populated; > > return 0; > > +err_delete_thread: > + thread__zput(etm->unknown_thread); > err_free_queues: > auxtrace_queues__free(&etm->queues); > session->auxtrace = NULL; > -- > 2.7.4 >
