Re: [PATCH 1/2] scsi: core: Fix sbitmap depth in scsi_realloc_sdev_budget_map()

[Ming Lei <ming.lei@redhat.com>]

On Tue, Mar 15, 2022 at 06:39:05PM +0800, John Garry wrote:
> In commit edb854a3680b ("scsi: core: Reallocate device's budget map on
> queue depth change"), the sbitmap for the device budget map may be
> reallocated after the slave device depth is configured.
> 
> When the sbitmap is reallocated we use the result from
> scsi_device_max_queue_depth() for the sbitmap size, but don't resize to
> match the actual device queue depth.
> 
> Fix by resizing the sbitmap after reallocating the budget sbitmap.
> 
> Signed-off-by: John Garry <john.garry@huawei.com>
> ---
>  drivers/scsi/scsi_scan.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
> index f4e6c68ac99e..2ef78083f1ef 100644
> --- a/drivers/scsi/scsi_scan.c
> +++ b/drivers/scsi/scsi_scan.c
> @@ -223,6 +223,8 @@ static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev,
>  	int ret;
>  	struct sbitmap sb_backup;
>  
> +	depth = min_t(unsigned int, depth, scsi_device_max_queue_depth(sdev));
> +
>  	/*
>  	 * realloc if new shift is calculated, which is caused by setting
>  	 * up one new default queue depth after calling ->slave_configure
> @@ -245,6 +247,9 @@ static int scsi_realloc_sdev_budget_map(struct scsi_device *sdev,
>  				scsi_device_max_queue_depth(sdev),
>  				new_shift, GFP_KERNEL,
>  				sdev->request_queue->node, false, true);
> +	if (!ret)
> +		sbitmap_resize(&sdev->budget_map, depth);
> +

Looks fine, 

Reviewed-by: Ming Lei <ming.lei@redhat.com>


Thanks,
Ming