block, bfq: handle NULL return value by bfq_init_rq()

As reported in [1], the call bfq_init_rq(rq) may return NULL in case
of OOM (in particular, if rq->elv.icq is NULL because memory
allocation failed in failed in ioc_create_icq()).

This commit handles this circumstance.

[1] https://lkml.org/lkml/2019/7/22/824

Cc: Hsin-Yi Wang <[email protected]>
Cc: Nicolas Boichat <[email protected]>
Cc: Doug Anderson <[email protected]>
Reported-by: Guenter Roeck <[email protected]>
Reported-by: Hsin-Yi Wang <[email protected]>
Reviewed-by: Guenter Roeck <[email protected]>
Signed-off-by: Paolo Valente <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

0 files changed, 0 insertions, 0 deletions