Hi, if, at boot, a legacy I/O scheduler is chosen for a device using blk-mq, or, viceversa, a blk-mq scheduler is chosen for a device using blk, then that scheduler is set and initialized without any check, driving the system into an inconsistent state. The purpose of this message is, first, to report this issue, and, second, to propose a possible fix in case you do consider this as a bug. Thanks, Paolo Paolo Valente (1): block: make elevator_get robust against cross blk/blk-mq choice block/elevator.c | 26 ++++++++++++++++++-------- 1 file changed, 18 insertions(+), 8 deletions(-) -- 2.10.0