Check the validity of subchanel before reading other fields in
the schib.
Fixes: d3683c055212 ("s390/cio: add dev_busid sysfs entry for each subchannel")
Reported-by: Cornelia Huck <cohuck@xxxxxxxxxx>
Signed-off-by: Vineeth Vijayan <vneethv@xxxxxxxxxxxxx>
---
drivers/s390/cio/css.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 2bc55ccf3f23..ce9e7517430f 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -437,8 +437,8 @@ static ssize_t dev_busid_show(struct device *dev,
struct subchannel *sch = to_subchannel(dev);
struct pmcw *pmcw = &sch->schib.pmcw;
- if ((pmcw->st == SUBCHANNEL_TYPE_IO ||
- pmcw->st == SUBCHANNEL_TYPE_MSG) && pmcw->dnv)
+ if ((pmcw->st == SUBCHANNEL_TYPE_IO && pmcw->dnv) ||
+ (pmcw->st == SUBCHANNEL_TYPE_MSG && pmcw->w))
return sysfs_emit(buf, "0.%x.%04x\n", sch->schid.ssid,
pmcw->dev);
else
--
2.25.1
