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]>
Acked-by: Mathieu Poirier <[email protected]>
---
tools/perf/util/cs-etm.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 6533b1a..69f21de 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);
}
@@ -1355,6 +1356,23 @@ 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 +1387,18 @@ 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
There have two spaces ahead function name cs_etm__set_pid_tid_cpu(), so
remove one space and correct indentation.
Signed-off-by: Leo Yan <[email protected]>
Acked-by: Mathieu Poirier <[email protected]>
---
tools/perf/util/cs-etm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 69f21de..822ba91 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -611,8 +611,8 @@ cs_etm__get_trace(struct cs_etm_buffer *buff, struct cs_etm_queue *etmq)
return buff->len;
}
-static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
- struct auxtrace_queue *queue)
+static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
+ struct auxtrace_queue *queue)
{
struct cs_etm_queue *etmq = queue->priv;
--
2.7.4
Em Thu, May 10, 2018 at 12:01:59PM +0800, Leo Yan escreveu:
> 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]>
> Acked-by: Mathieu Poirier <[email protected]>
Thanks, applied to perf/urgent.
And please use a more descriptive, eye catching summary, something like:
perf cs-etm: Fix segfault when accessing NULL unknown_thread variable
:-)
- Arnaldo
On Fri, May 11, 2018 at 10:48:00AM -0300, Arnaldo Carvalho de Melo wrote:
> Em Thu, May 10, 2018 at 12:01:59PM +0800, Leo Yan escreveu:
> > 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]>
> > Acked-by: Mathieu Poirier <[email protected]>
>
> Thanks, applied to perf/urgent.
>
> And please use a more descriptive, eye catching summary, something like:
>
> perf cs-etm: Fix segfault when accessing NULL unknown_thread variable
>
> :-)
Thanks for suggestion. Indeed, this patch is a fix rather than
a new feature, subject should reflect it.
Thanks,
Leo Yan
Commit-ID: 46d53620044f7b574c0f3216f8b4f2ce3559ce31
Gitweb: https://git.kernel.org/tip/46d53620044f7b574c0f3216f8b4f2ce3559ce31
Author: Leo Yan <[email protected]>
AuthorDate: Thu, 10 May 2018 12:01:59 +0800
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Fri, 11 May 2018 10:45:23 -0300
perf cs-etm: Support unknown_thread in cs_etm_auxtrace
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 a segmentation fault when
thread__find_addr_map() accesses the thread handler.
This commit creates a 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]>
Acked-by: Mathieu Poirier <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/util/cs-etm.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 40020b1ca54f..2bf28b5acc08 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);
}
@@ -1357,6 +1358,23 @@ 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;
@@ -1371,16 +1389,18 @@ 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;
Commit-ID: 3a0887997d6731e1005ba09c93aa5c2898c78931
Gitweb: https://git.kernel.org/tip/3a0887997d6731e1005ba09c93aa5c2898c78931
Author: Leo Yan <[email protected]>
AuthorDate: Thu, 10 May 2018 12:02:00 +0800
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Fri, 11 May 2018 10:46:36 -0300
perf cs-etm: Remove redundant space
There have two spaces ahead function name cs_etm__set_pid_tid_cpu(), so
remove one space and correct indentation.
Signed-off-by: Leo Yan <[email protected]>
Acked-by: Mathieu Poirier <[email protected]>
Cc: Alexander Shishkin <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/util/cs-etm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
index 2bf28b5acc08..bf16dc9ee507 100644
--- a/tools/perf/util/cs-etm.c
+++ b/tools/perf/util/cs-etm.c
@@ -613,8 +613,8 @@ cs_etm__get_trace(struct cs_etm_buffer *buff, struct cs_etm_queue *etmq)
return buff->len;
}
-static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
- struct auxtrace_queue *queue)
+static void cs_etm__set_pid_tid_cpu(struct cs_etm_auxtrace *etm,
+ struct auxtrace_queue *queue)
{
struct cs_etm_queue *etmq = queue->priv;