Re: [PATCH] drm/xe: fixup xe_alloc_pf_queue

[Matthew Brost <matthew.brost@intel.com>]

On Wed, Aug 21, 2024 at 06:19:18PM +0100, Matthew Auld wrote:
> kzalloc expects number of bytes, therefore we should convert the number
> of dw into bytes, otherwise we are likely just accessing beyond the
> array causing all kinds of carnage. Also fixup the error handling while
> we are here.
> 
> Fixes: 3338e4f90c14 ("drm/xe: Use topology to determine page fault queue size")
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>
> Cc: Stuart Summers <stuart.summers@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> ---
>  drivers/gpu/drm/xe/xe_gt_pagefault.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_gt_pagefault.c b/drivers/gpu/drm/xe/xe_gt_pagefault.c
> index 401c0527d914..e4510e56e4a2 100644
> --- a/drivers/gpu/drm/xe/xe_gt_pagefault.c
> +++ b/drivers/gpu/drm/xe/xe_gt_pagefault.c
> @@ -417,7 +417,10 @@ static int xe_alloc_pf_queue(struct xe_gt *gt, struct pf_queue *pf_queue)
>  		(num_eus + XE_NUM_HW_ENGINES) * PF_MSG_LEN_DW;
>  
>  	pf_queue->gt = gt;
> -	pf_queue->data = kzalloc(pf_queue->num_dw, GFP_KERNEL);
> +	pf_queue->data = kzalloc(pf_queue->num_dw * sizeof(u32), GFP_KERNEL);

I merged this s/kzalloc/kcalloc based on feedback from dim.

Matt

> +	if (!pf_queue->data)
> +		return -ENOMEM;
> +
>  	spin_lock_init(&pf_queue->lock);
>  	INIT_WORK(&pf_queue->worker, pf_queue_work_func);
>  
> -- 
> 2.46.0
>