diff options
| author | Julian Wiedmann <jwi@linux.ibm.com> | 2021-01-07 18:24:41 +0100 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2021-01-07 18:54:06 -0800 |
| commit | b41b554c1ee75070a14c02a88496b1f231c7eacc (patch) | |
| tree | 640acf6ee4ddeb467d832a99b68242f35deaa7ae /drivers/s390/net/qeth_l2_main.c | |
| parent | 0b9902c1fcc59ba75268386c0420a554f8844168 (diff) | |
| download | lwn-b41b554c1ee75070a14c02a88496b1f231c7eacc.tar.gz lwn-b41b554c1ee75070a14c02a88496b1f231c7eacc.zip | |
s390/qeth: fix locking for discipline setup / removal
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>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/s390/net/qeth_l2_main.c')
| -rw-r--r-- | drivers/s390/net/qeth_l2_main.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c index 37279b1e29f6..4254caf1d9b6 100644 --- a/drivers/s390/net/qeth_l2_main.c +++ b/drivers/s390/net/qeth_l2_main.c @@ -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) |