diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2019-04-03 09:13:34 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-05-16 19:42:21 +0200 |
| commit | 2c3414141b9dd7754931efbe6dfb66b9acf24d39 (patch) | |
| tree | 10135a873fa61ee3dfc912a527d58a07558faa7f /drivers/s390/char/raw3270.c | |
| parent | 307c65e2fd65325afacfe5630fbb4563bc80d9c0 (diff) | |
s390/3270: fix lockdep false positive on view->lock
[ Upstream commit 5712f3301a12c0c3de9cc423484496b0464f2faf ]
The spinlock in the raw3270_view structure is used by con3270, tty3270
and fs3270 in different ways. For con3270 the lock can be acquired in
irq context, for tty3270 and fs3270 the highest context is bh.
Lockdep sees the view->lock as a single class and if the 3270 driver
is used for the console the following message is generated:
WARNING: inconsistent lock state
5.1.0-rc3-05157-g5c168033979d #12 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
swapper/0/1 [HC0[0]:SC1[1]:HE1:SE0] takes:
(____ptrval____) (&(&view->lock)->rlock){?.-.}, at: tty3270_update+0x7c/0x330
Introduce a lockdep subclass for the view lock to distinguish bh from
irq locks.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/s390/char/raw3270.c')
| -rw-r--r-- | drivers/s390/char/raw3270.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c index 5d4f053d7c38..0f47fec35acc 100644 --- a/drivers/s390/char/raw3270.c +++ b/drivers/s390/char/raw3270.c @@ -919,7 +919,7 @@ raw3270_deactivate_view(struct raw3270_view *view) * Add view to device with minor "minor". */ int -raw3270_add_view(struct raw3270_view *view, struct raw3270_fn *fn, int minor) +raw3270_add_view(struct raw3270_view *view, struct raw3270_fn *fn, int minor, int subclass) { unsigned long flags; struct raw3270 *rp; @@ -941,6 +941,7 @@ raw3270_add_view(struct raw3270_view *view, struct raw3270_fn *fn, int minor) view->cols = rp->cols; view->ascebc = rp->ascebc; spin_lock_init(&view->lock); + lockdep_set_subclass(&view->lock, subclass); list_add(&view->list, &rp->view_list); rc = 0; spin_unlock_irqrestore(get_ccwdev_lock(rp->cdev), flags); |