diff options
| author | Peter Oberparleiter <peter.oberparleiter@de.ibm.com> | 2008-08-21 19:46:39 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2008-08-21 19:46:41 +0200 |
| commit | 91c36919a456589f4f073671474a1f899e0d3c2b (patch) | |
| tree | 63cb2ee1afd9b00bf2ea4959482d58f402bb21f3 /drivers/s390/block | |
| parent | 49fd38bdaa96f093fcad3176a781a4d0de8f8602 (diff) | |
[S390] cio: call ccw driver notify function with lock held
Calling a ccw driver's notify function without the ccw device lock
held opens up a race window between discovery and handling of a change
in the device operational state. As a result, the device driver may
encounter unexpected device malfunction, leading to out-of-retry
situations or similar.
Remove race by extending the ccw device lock from state change
discovery to the calling of the notify function.
Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/block')
| -rw-r--r-- | drivers/s390/block/dasd.c | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c index 1b6c52ef733..acb78017e7d 100644 --- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -2333,13 +2333,11 @@ int dasd_generic_notify(struct ccw_device *cdev, int event) { struct dasd_device *device; struct dasd_ccw_req *cqr; - unsigned long flags; int ret; - device = dasd_device_from_cdev(cdev); + device = dasd_device_from_cdev_locked(cdev); if (IS_ERR(device)) return 0; - spin_lock_irqsave(get_ccwdev_lock(cdev), flags); ret = 0; switch (event) { case CIO_GONE: @@ -2369,7 +2367,6 @@ int dasd_generic_notify(struct ccw_device *cdev, int event) ret = 1; break; } - spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags); dasd_put_device(device); return ret; } |