diff options
| author |   Vineeth Vijayan <vneethv@linux.ibm.com> | 2026-09-10 11:32:02 +0200 |
|---|---|---|
| committer |   Heiko Carstens <hca@linux.ibm.com> | 2026-09-17 06:59:41 +0200 |
| commit | f6f2985eabdb2bfdc82ce90a1ea3ec53ba795f34 (patch) | |
| tree | 7488713f727af4adf543aec4a6ec59fb19c8261d | |
| parent | s390/cio: Fix cio_update_schib() to not cache invalid schib (diff) | |
s390/cio: Check pmcw.dnv before pmcw.ena in I/O entry points
The device number valid (dnv) bit in the PMCW must be checked before
acting on any other PMCW fields for IO-type subchannels. A subchannel
with dnv=0 has no valid device number associated, making it meaningless
to evaluate the enabled (ena) state or issue any I/O instruction against
it.
Reported-by: William Bezenah <wbezenah@linux.ibm.com>
Signed-off-by: Vineeth Vijayan <vneethv@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Fixes: 8c58a229688c ("s390/cio: Do not unregister the subchannel based on DNV")
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
| -rw-r--r-- | drivers/s390/cio/device_ops.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c index 61c07b4a0fe8..c1ba4a19368f 100644 --- a/drivers/s390/cio/device_ops.c +++ b/drivers/s390/cio/device_ops.c @@ -142,6 +142,8 @@ int ccw_device_clear(struct ccw_device *cdev, unsigned long intparm) if (!cdev || !cdev->dev.parent) return -ENODEV; sch = to_subchannel(cdev->dev.parent); + if (!sch->schib.pmcw.dnv) + return -ENODEV; if (!sch->schib.pmcw.ena) return -EINVAL; if (cdev->private->state == DEV_STATE_NOT_OPER) @@ -198,6 +200,8 @@ int ccw_device_start_timeout_key(struct ccw_device *cdev, struct ccw1 *cpa, if (!cdev || !cdev->dev.parent) return -ENODEV; sch = to_subchannel(cdev->dev.parent); + if (!sch->schib.pmcw.dnv) + return -ENODEV; if (!sch->schib.pmcw.ena) return -EINVAL; if (cdev->private->state == DEV_STATE_NOT_OPER) @@ -379,6 +383,8 @@ int ccw_device_halt(struct ccw_device *cdev, unsigned long intparm) if (!cdev || !cdev->dev.parent) return -ENODEV; sch = to_subchannel(cdev->dev.parent); + if (!sch->schib.pmcw.dnv) + return -ENODEV; if (!sch->schib.pmcw.ena) return -EINVAL; if (cdev->private->state == DEV_STATE_NOT_OPER) @@ -413,6 +419,8 @@ int ccw_device_resume(struct ccw_device *cdev) if (!cdev || !cdev->dev.parent) return -ENODEV; sch = to_subchannel(cdev->dev.parent); + if (!sch->schib.pmcw.dnv) + return -ENODEV; if (!sch->schib.pmcw.ena) return -EINVAL; if (cdev->private->state == DEV_STATE_NOT_OPER) @@ -548,6 +556,8 @@ int ccw_device_tm_start_timeout_key(struct ccw_device *cdev, struct tcw *tcw, int rc; sch = to_subchannel(cdev->dev.parent); + if (!sch->schib.pmcw.dnv) + return -ENODEV; if (!sch->schib.pmcw.ena) return -EINVAL; if (cdev->private->state == DEV_STATE_VERIFY) { @@ -694,6 +704,8 @@ int ccw_device_tm_intrg(struct ccw_device *cdev) { struct subchannel *sch = to_subchannel(cdev->dev.parent); + if (!sch->schib.pmcw.dnv) + return -ENODEV; if (!sch->schib.pmcw.ena) return -EINVAL; if (cdev->private->state != DEV_STATE_ONLINE) |