From: Cornelia Huck cohuck@redhat.com
[ Upstream commit 05ce3e53f375295c2940390b2b429e506e07655c ]
The common I/O layer delays the ADD uevent for subchannels and delegates generating this uevent to the individual subchannel drivers. The io_subchannel driver will do so when the associated ccw_device has been registered -- but unconditionally, so more ADD uevents will be generated if a subchannel has been unbound from the io_subchannel driver and later rebound.
To fix this, only generate the ADD event if uevents were still suppressed for the device.
Fixes: fa1a8c23eb7d ("s390: cio: Delay uevents for subchannels") Message-Id: 20200327124503.9794-2-cohuck@redhat.com Reported-by: Boris Fiuczynski fiuczy@linux.ibm.com Reviewed-by: Peter Oberparleiter oberpar@linux.ibm.com Reviewed-by: Boris Fiuczynski fiuczy@linux.ibm.com Signed-off-by: Cornelia Huck cohuck@redhat.com Signed-off-by: Vasily Gorbik gor@linux.ibm.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/s390/cio/device.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)
diff --git a/drivers/s390/cio/device.c b/drivers/s390/cio/device.c index 0c6245fc77069..983f9c9e08deb 100644 --- a/drivers/s390/cio/device.c +++ b/drivers/s390/cio/device.c @@ -849,8 +849,10 @@ static void io_subchannel_register(struct ccw_device *cdev) * Now we know this subchannel will stay, we can throw * our delayed uevent. */ - dev_set_uevent_suppress(&sch->dev, 0); - kobject_uevent(&sch->dev.kobj, KOBJ_ADD); + if (dev_get_uevent_suppress(&sch->dev)) { + dev_set_uevent_suppress(&sch->dev, 0); + kobject_uevent(&sch->dev.kobj, KOBJ_ADD); + } /* make it known to the system */ ret = ccw_device_add(cdev); if (ret) { @@ -1058,8 +1060,11 @@ static int io_subchannel_probe(struct subchannel *sch) * Throw the delayed uevent for the subchannel, register * the ccw_device and exit. */ - dev_set_uevent_suppress(&sch->dev, 0); - kobject_uevent(&sch->dev.kobj, KOBJ_ADD); + if (dev_get_uevent_suppress(&sch->dev)) { + /* should always be the case for the console */ + dev_set_uevent_suppress(&sch->dev, 0); + kobject_uevent(&sch->dev.kobj, KOBJ_ADD); + } cdev = sch_get_cdev(sch); rc = ccw_device_add(cdev); if (rc) {