From: Ming Lei ming.lei@redhat.com
[ Upstream commit 8312cd3a7b835ae3033a679e5f0014a40e7891c5 ]
The megaraid SCSI driver sets set->nr_maps as 3 if poll_queues is > 0, and blk-mq actually initializes each map's nr_queues as nr_hw_queues. Consequently the driver has to clear READ queue map's nr_queues, otherwise the queue map becomes broken if poll_queues is set as non-zero.
Link: https://lore.kernel.org/r/20220706125942.528533-1-ming.lei@redhat.com Fixes: 9e4bec5b2a23 ("scsi: megaraid_sas: mq_poll support") Cc: Kashyap Desai kashyap.desai@broadcom.com Cc: sumit.saxena@broadcom.com Cc: chandrakanth.patil@broadcom.com Cc: linux-block@vger.kernel.org Cc: Hannes Reinecke hare@suse.de Reported-by: Guangwu Zhang guazhang@redhat.com Tested-by: Guangwu Zhang guazhang@redhat.com Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Ming Lei ming.lei@redhat.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/megaraid/megaraid_sas_base.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c index db6793608447..f5deb0e561a9 100644 --- a/drivers/scsi/megaraid/megaraid_sas_base.c +++ b/drivers/scsi/megaraid/megaraid_sas_base.c @@ -3195,6 +3195,9 @@ static int megasas_map_queues(struct Scsi_Host *shost) qoff += map->nr_queues; offset += map->nr_queues;
+ /* we never use READ queue, so can't cheat blk-mq */ + shost->tag_set.map[HCTX_TYPE_READ].nr_queues = 0; + /* Setup Poll hctx */ map = &shost->tag_set.map[HCTX_TYPE_POLL]; map->nr_queues = instance->iopoll_q_count;