From 4e56296d471a827fdd244cfdb6a1e62fc3af7af0 Mon Sep 17 00:00:00 2001 From: Ralph Wuerthner Date: Wed, 4 Oct 2006 20:02:05 +0200 Subject: [S390] zcrypt device registration/unregistration race. Fix a race condition during AP device registration and unregistration. Signed-off-by: Ralph Wuerthner Signed-off-by: Martin Schwidefsky --- drivers/s390/crypto/ap_bus.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c index 6ed0985c0c9..cd30f37fcea 100644 --- a/drivers/s390/crypto/ap_bus.c +++ b/drivers/s390/crypto/ap_bus.c @@ -449,8 +449,6 @@ static int ap_device_probe(struct device *dev) ap_dev->drv = ap_drv; rc = ap_drv->probe ? ap_drv->probe(ap_dev) : -ENODEV; - if (rc) - ap_dev->unregistered = 1; return rc; } @@ -487,14 +485,7 @@ static int ap_device_remove(struct device *dev) struct ap_device *ap_dev = to_ap_dev(dev); struct ap_driver *ap_drv = ap_dev->drv; - spin_lock_bh(&ap_dev->lock); - __ap_flush_queue(ap_dev); - /** - * set ->unregistered to 1 while holding the lock. This prevents - * new messages to be put on the queue from now on. - */ - ap_dev->unregistered = 1; - spin_unlock_bh(&ap_dev->lock); + ap_flush_queue(ap_dev); if (ap_drv->remove) ap_drv->remove(ap_dev); return 0; @@ -763,6 +754,7 @@ static void ap_scan_bus(void *data) break; ap_dev->qid = qid; ap_dev->queue_depth = queue_depth; + ap_dev->unregistered = 1; spin_lock_init(&ap_dev->lock); INIT_LIST_HEAD(&ap_dev->pendingq); INIT_LIST_HEAD(&ap_dev->requestq); @@ -784,7 +776,12 @@ static void ap_scan_bus(void *data) /* Add device attributes. */ rc = sysfs_create_group(&ap_dev->device.kobj, &ap_dev_attr_group); - if (rc) + if (!rc) { + spin_lock_bh(&ap_dev->lock); + ap_dev->unregistered = 0; + spin_unlock_bh(&ap_dev->lock); + } + else device_unregister(&ap_dev->device); } } @@ -970,6 +967,8 @@ void ap_queue_message(struct ap_device *ap_dev, struct ap_message *ap_msg) rc = __ap_queue_message(ap_dev, ap_msg); if (!rc) wake_up(&ap_poll_wait); + if (rc == -ENODEV) + ap_dev->unregistered = 1; } else { ap_dev->drv->receive(ap_dev, ap_msg, ERR_PTR(-ENODEV)); rc = 0; @@ -1028,6 +1027,8 @@ static int __ap_poll_all(struct device *dev, void *data) spin_lock(&ap_dev->lock); if (!ap_dev->unregistered) { rc = ap_poll_queue(to_ap_dev(dev), (unsigned long *) data); + if (rc) + ap_dev->unregistered = 1; } else rc = 0; spin_unlock(&ap_dev->lock); -- cgit v1.2.3