Re: [PATCH] cxl/mem: Correct full ID range allocation

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Wed,  8 Feb 2023 10:19:44 -0800
Davidlohr Bueso <dave@stgolabs.net> wrote:

> For ID allocations we want 0-(max-1), ie: smatch complains:
> 
> 	 error: Calling ida_alloc_range() with a 'max' argument which is a power of 2. -1 missing?
> 
> Correct this and also replace the call to use the max() flavor instead.
> 
> Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>

I'm not sure I follow the smatch error always applying, but definitely suspicious here

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>  drivers/cxl/core/memdev.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
> index a74a93310d26..12bd9ddaba22 100644
> --- a/drivers/cxl/core/memdev.c
> +++ b/drivers/cxl/core/memdev.c
> @@ -242,7 +242,7 @@ static struct cxl_memdev *cxl_memdev_alloc(struct cxl_dev_state *cxlds,
>  	if (!cxlmd)
>  		return ERR_PTR(-ENOMEM);
>  
> -	rc = ida_alloc_range(&cxl_memdev_ida, 0, CXL_MEM_MAX_DEVS, GFP_KERNEL);
> +	rc = ida_alloc_max(&cxl_memdev_ida, CXL_MEM_MAX_DEVS - 1, GFP_KERNEL);
>  	if (rc < 0)
>  		goto err;
>  	cxlmd->id = rc;