path: root/drivers/s390/crypto/ap_bus.c
diff options
authorHarald Freudenberger <freude@linux.ibm.com>2018-11-09 14:59:24 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2018-11-27 10:43:35 +0100
commit104f708fd1241b22f808bdf066ab67dc5a051de5 (patch)
treecd5e724507ae874b9d661f09fe7887180d41f74a /drivers/s390/crypto/ap_bus.c
parent613a41b0d16e617f46776a93b975a1eeea96417c (diff)
s390/zcrypt: reinit ap queue state machine during device probe
Until the vfio-ap driver came into live there was a well known agreement about the way how ap devices are initialized and their states when the driver's probe function is called. However, the vfio device driver when receiving an ap queue device does additional resets thereby removing the registration for interrupts for the ap device done by the ap bus core code. So when later the vfio driver releases the device and one of the default zcrypt drivers takes care of the device the interrupt registration needs to get renewed. The current code does no renew and result is that requests send into such a queue will never see a reply processed - the application hangs. This patch adds a function which resets the aq queue state machine for the ap queue device and triggers the walk through the initial states (which are reset and registration for interrupts). This function is now called before the driver's probe function is invoked. When the association between driver and device is released, the driver's remove function is called. The current implementation calls a ap queue function ap_queue_remove(). This invokation has been moved to the ap bus function to make the probe / remove pair for ap bus and drivers more symmetric. Fixes: 7e0bdbe5c21c ("s390/zcrypt: AP bus support for alternate driver(s)") Cc: stable@vger.kernel.org # 4.19+ Signed-off-by: Harald Freudenberger <freude@linux.ibm.com> Reviewd-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewd-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/crypto/ap_bus.c')
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 048665e4f13d..9f5a201c4c87 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -775,6 +775,8 @@ static int ap_device_probe(struct device *dev)
drvres = ap_drv->flags & AP_DRIVER_FLAG_DEFAULT;
if (!!devres != !!drvres)
return -ENODEV;
+ /* (re-)init queue's state machine */
+ ap_queue_reinit_state(to_ap_queue(dev));
/* Add queue/card to list of active queues/cards */
@@ -807,6 +809,8 @@ 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;
+ if (is_queue_dev(dev))
+ ap_queue_remove(to_ap_queue(dev));
if (ap_drv->remove)
@@ -1444,10 +1448,6 @@ static void ap_scan_bus(struct work_struct *unused)
aq->ap_dev.device.parent = &ac->ap_dev.device;
"%02x.%04x", id, dom);
- /* Start with a device reset */
- spin_lock_bh(&aq->lock);
- ap_wait(ap_sm_event(aq, AP_EVENT_POLL));
- spin_unlock_bh(&aq->lock);
/* Register device */
rc = device_register(&aq->ap_dev.device);
if (rc) {

Privacy Policy