Re: [PATCH v5 04/12] iommu/vt-d: Add 256-bit invalidation descriptor support

[Joerg Roedel]

On Wed, Nov 28, 2018 at 11:54:41AM +0800, Lu Baolu wrote:
> -
> -	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO, 0);
> +	/*
> +	 * Need two pages to accommodate 256 descriptors of 256 bits each
> +	 * if the remapping hardware supports scalable mode translation.
> +	 */
> +	desc_page = alloc_pages_node(iommu->node, GFP_ATOMIC | __GFP_ZERO,
> +				     !!ecap_smts(iommu->ecap));


Same here, does the allocation really need GFP_ATOMIC?

>  struct q_inval {
>  	raw_spinlock_t  q_lock;
> -	struct qi_desc  *desc;          /* invalidation queue */
> +	void		*desc;          /* invalidation queue */
>  	int             *desc_status;   /* desc status */
>  	int             free_head;      /* first free entry */
>  	int             free_tail;      /* last free entry */

Why do you switch the pointer to void* ?


	Joerg