4.18-stable review patch. If anyone has any objections, please let me know.
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From: Stefan Haberland sth@linux.ibm.com
[ Upstream commit 7c6553d4db03350dad0110c3224194c19df76a8f ]
Fix a panic that occurs for a device that got an error in dasd_eckd_check_characteristics() during online processing. For example the read configuration data command may have failed.
If this error occurs the device is not being set online and the earlier invoked steps during online processing are rolled back. Therefore dasd_eckd_uncheck_device() is called which needs a valid private structure. But this pointer is not valid if dasd_eckd_check_characteristics() has failed.
Check for a valid device->private pointer to prevent a panic.
Reviewed-by: Jan Hoeppner hoeppner@linux.ibm.com Signed-off-by: Stefan Haberland sth@linux.ibm.com Signed-off-by: Martin Schwidefsky schwidefsky@de.ibm.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/s390/block/dasd_eckd.c | 3 +++ 1 file changed, 3 insertions(+)
--- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -1780,6 +1780,9 @@ static void dasd_eckd_uncheck_device(str struct dasd_eckd_private *private = device->private; int i;
+ if (!private) + return; + dasd_alias_disconnect_device_from_lcu(device); private->ned = NULL; private->sneq = NULL;