[PATCH 5.11 011/342] s390/cio: remove invalid condition on IO_SCH_UNREG

From: Greg Kroah-Hartman
Date: Mon May 10 2021 - 07:21:18 EST


From: Vineeth Vijayan <vneethv@xxxxxxxxxxxxx>

commit 2f7484fd73729f89085fe08d683f5a8d9e17fe99 upstream.

The condition to check the cdev pointer validity on
css_sch_device_unregister() is a leftover from the 'commit 8cc0dcfdc1c0
("s390/cio: remove pm support from ccw bus driver")'. This could lead to a
situation, where detaching the device is not happening completely. Remove
this invalid condition in the IO_SCH_UNREG case.

Link: https://lore.kernel.org/r/20210423100843.2230969-1-vneethv@xxxxxxxxxxxxx
Fixes: 8cc0dcfdc1c0 ("s390/cio: remove pm support from ccw bus driver")
Reported-by: Christian Ehrhardt <christian.ehrhardt@xxxxxxxxxxxxx>
Suggested-by: Christian Ehrhardt <christian.ehrhardt@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Vineeth Vijayan <vneethv@xxxxxxxxxxxxx>
Tested-by: Julian Wiedmann <jwi@xxxxxxxxxxxxx>
Reviewed-by: Peter Oberparleiter <oberpar@xxxxxxxxxxxxx>
Tested-by: Christian Ehrhardt <christian.ehrhardt@xxxxxxxxxxxxx>
Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/s390/cio/device.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/s390/cio/device.c
+++ b/drivers/s390/cio/device.c
@@ -1525,8 +1525,7 @@ static int io_subchannel_sch_event(struc
switch (action) {
case IO_SCH_ORPH_UNREG:
case IO_SCH_UNREG:
- if (!cdev)
- css_sch_device_unregister(sch);
+ css_sch_device_unregister(sch);
break;
case IO_SCH_ORPH_ATTACH:
case IO_SCH_UNREG_ATTACH: