On 2020-04-09 14:45, Luis Chamberlain wrote: > blk_put_queue() puts decrements the refcount for the request_queue ^^^^ can this word be left out? > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index 8b1cab52cef9..46fee1ef92e3 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -614,6 +614,7 @@ struct request_queue { > #define QUEUE_FLAG_PCI_P2PDMA 25 /* device supports PCI p2p requests */ > #define QUEUE_FLAG_ZONE_RESETALL 26 /* supports Zone Reset All */ > #define QUEUE_FLAG_RQ_ALLOC_TIME 27 /* record rq->alloc_time_ns */ > +#define QUEUE_FLAG_DEFER_REMOVAL 28 /* defer queue removal */ > > #define QUEUE_FLAG_MQ_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ > (1 << QUEUE_FLAG_SAME_COMP)) > @@ -648,6 +649,8 @@ bool blk_queue_flag_test_and_set(unsigned int flag, struct request_queue *q); > #else > #define blk_queue_rq_alloc_time(q) false > #endif > +#define blk_queue_defer_removal(q) \ > + test_bit(QUEUE_FLAG_DEFER_REMOVAL, &(q)->queue_flags) Since blk_queue_defer_removal() has no callers the code that depends on QUEUE_FLAG_DEFER_REMOVAL to be set will be subject to bitrot. It would make me happy if the QUEUE_FLAG_DEFER_REMOVAL flag and the code that depends on that flag would be removed. Please add a might_sleep() call in blk_put_queue() since with this patch applied it is no longer allowed to call blk_put_queue() from atomic context. Thanks, Bart.