@@ -6585,6 +6585,7 @@ static int qeth_core_probe_device(struct ccwgroup_device *gdev)
break;
default:
card->info.layer_enforced = true;
+ /* It's so early that we don't need the discipline_mutex yet. */
rc = qeth_core_load_discipline(card, enforced_disc);
if (rc)
goto err_load;
@@ -6617,10 +6618,12 @@ static void qeth_core_remove_device(struct ccwgroup_device *gdev)
QETH_CARD_TEXT(card, 2, "removedv");
+ mutex_lock(&card->discipline_mutex);
if (card->discipline) {
card->discipline->remove(gdev);
qeth_core_free_discipline(card);
}
+ mutex_unlock(&card->discipline_mutex);
qeth_free_qdio_queues(card);
@@ -6635,6 +6638,7 @@ static int qeth_core_set_online(struct ccwgroup_device *gdev)
int rc = 0;
enum qeth_discipline_id def_discipline;
+ mutex_lock(&card->discipline_mutex);
if (!card->discipline) {
def_discipline = IS_IQD(card) ? QETH_DISCIPLINE_LAYER3 :
QETH_DISCIPLINE_LAYER2;
@@ -6648,11 +6652,10 @@ static int qeth_core_set_online(struct ccwgroup_device *gdev)
}
}
- mutex_lock(&card->discipline_mutex);
rc = qeth_set_online(card, card->discipline);
- mutex_unlock(&card->discipline_mutex);
err:
+ mutex_unlock(&card->discipline_mutex);
return rc;
}
@@ -2207,11 +2207,8 @@ static void qeth_l2_remove_device(struct ccwgroup_device *gdev)
qeth_set_allowed_threads(card, 0, 1);
wait_event(card->wait_q, qeth_threads_running(card, 0xffffffff) == 0);
- if (gdev->state == CCWGROUP_ONLINE) {
- mutex_lock(&card->discipline_mutex);
+ if (gdev->state == CCWGROUP_ONLINE)
qeth_set_offline(card, card->discipline, false);
- mutex_unlock(&card->discipline_mutex);
- }
cancel_work_sync(&card->close_dev_work);
if (card->dev->reg_state == NETREG_REGISTERED)
@@ -1970,11 +1970,8 @@ static void qeth_l3_remove_device(struct ccwgroup_device *cgdev)
qeth_set_allowed_threads(card, 0, 1);
wait_event(card->wait_q, qeth_threads_running(card, 0xffffffff) == 0);
- if (cgdev->state == CCWGROUP_ONLINE) {
- mutex_lock(&card->discipline_mutex);
+ if (cgdev->state == CCWGROUP_ONLINE)
qeth_set_offline(card, card->discipline, false);
- mutex_unlock(&card->discipline_mutex);
- }
cancel_work_sync(&card->close_dev_work);
if (card->dev->reg_state == NETREG_REGISTERED)
Due to insufficient locking, qeth_core_set_online() and qeth_dev_layer2_store() can run in parallel, both attempting to load & setup the discipline (and stepping on each other toes along the way). A similar race can also occur between qeth_core_remove_device() and qeth_dev_layer2_store(). Access to .discipline is meant to be protected by the discipline_mutex, so add/expand the locking in qeth_core_remove_device() and qeth_core_set_online(). Adjust the locking in qeth_l*_remove_device() accordingly, as it's now handled by the callers in a consistent manner. Based on an initial patch by Ursula Braun. Fixes: 9dc48ccc68b9 ("qeth: serialize sysfs-triggered device configurations") Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com> Reviewed-by: Alexandra Winter <wintera@linux.ibm.com> --- drivers/s390/net/qeth_core_main.c | 7 +++++-- drivers/s390/net/qeth_l2_main.c | 5 +---- drivers/s390/net/qeth_l3_main.c | 5 +---- 3 files changed, 7 insertions(+), 10 deletions(-)