On Tue, Jan 30, 2018 at 03:37:38AM +0000, Bart Van Assche wrote: > On Tue, 2018-01-30 at 11:31 +0800, Ming Lei wrote: > > Please take a look at drivers, when BLK_STS_RESOURCE is returned, who > > will call blk_mq_delay_run_hw_queue() for drivers? > > As you know the SCSI and dm drivers in kernel v4.15 already call that function > whenever necessary. We have concluded that it is generic issue which need generic solution[1]. [1] https://marc.info/?l=linux-kernel&m=151638176727612&w=2 [ming@ming linux]$ git grep -n BLK_STS_RESOURCE ./drivers/ | wc -l 43 Almost every driver need this kind of change if BLK_STS_RESOURCE is returned from IO path. And the failure can be caused by kmalloc(GFP_ATOMIC), DMA Mapping, or what ever. Thanks, Ming
