On Fri, May 18, 2018 at 9:42 PM, 胡海 <huhai@xxxxxxxxxx> wrote: > Author: huhai <huhai@xxxxxxxxxx> > Date: Fri May 18 17:09:56 2018 +0800 > > blk-mq: make sure that correct hctx->dispatch_from is set > > When the number of hardware queues is changed, the drivers will call > blk_mq_update_nr_hw_queues() to remap hardware queues, and then > the ctx mapped on hctx will also change, but the current code forgets to > make sure that correct hctx->dispatch_from is set, and hctx->dispatch_from > may point to a ctx that does not belong to the current hctx. > > Signed-off-by: huhai <huhai@xxxxxxxxxx> > > diff --git a/block/blk-mq.c b/block/blk-mq.c > index 2545081..55d8a3d 100644 > --- a/block/blk-mq.c > +++ b/block/blk-mq.c > @@ -2214,6 +2214,8 @@ static void blk_mq_map_swqueue(struct request_queue *q) > hctx->tags = set->tags[i]; > WARN_ON(!hctx->tags); > > + hctx->dispatch_from = NULL; > + > /* > * Set the map size to the number of mapped software queues. > * This is more accurate and more efficient than looping Good catch, Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx> Thanks, Ming Lei
