From a4751f157c194431fae9e9c493f456df8272b871 Mon Sep 17 00:00:00 2001 From: Vineeth Vijayan Date: Fri, 5 Nov 2021 16:44:51 +0100 Subject: [PATCH] s390/cio: check the subchannel validity for dev_busid Check the validity of subchanel before reading other fields in the schib. Fixes: d3683c055212 ("s390/cio: add dev_busid sysfs entry for each subchannel") CC: Reported-by: Cornelia Huck Signed-off-by: Vineeth Vijayan Reviewed-by: Cornelia Huck Link: https://lore.kernel.org/r/20211105154451.847288-1-vneethv@linux.ibm.com Signed-off-by: Vasily Gorbik --- 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