Re: [PATCH 24/27] block: remove QUEUE_FLAG_DISCARD

[Keith Busch <kbusch@xxxxxxxxxx>]

On Sat, Apr 09, 2022 at 06:50:40AM +0200, Christoph Hellwig wrote:
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index efb85c6d8e2d5..7e07dd69262a7 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -1607,10 +1607,8 @@ static void nvme_config_discard(struct gendisk *disk, 
> struct nvme_ns *ns)
>       struct request_queue *queue = disk->queue;
>       u32 size = queue_logical_block_size(queue);
>  
> -     if (ctrl->max_discard_sectors == 0) {
> -             blk_queue_flag_clear(QUEUE_FLAG_DISCARD, queue);
> +     if (ctrl->max_discard_sectors == 0)
>               return;
> -     }

I think we need to update the queue limit in this condition. While unlikley,
the flag was cleared here in case the device changed support for discard from
the previous reset.