Re: [PATCH] drm/xe/madvise: Remove unreachable madvise_funcs NULL check

["Wang, X" <x.wang@intel.com>]

On 9/14/2026 18:12, Shuicheng Lin wrote:
> The NULL check on madvise_funcs[attr_type] in xe_vm_madvise_ioctl()
> is unreachable. madvise_args_are_sane() already validates args->type
> via a switch statement whose default case rejects any type not present
> in madvise_funcs[]. Every type that passes the sanity check has a
> corresponding entry in the table.
>
> Beyond being dead code, the check's error path (goto err_fini) would
> also skip xe_svm_notifier_unlock() if it were somehow reached with
> has_svm_userptr_vmas set, since err_fini only tears down the drm_exec.
> Removing the check eliminates both the redundancy and the latent
> unwind hazard.
>
> No functional change.
>
> Assisted-by: LLM
The code change looks good to me. One small commit-message nit:
Documentation/process/coding-assistants.rst specifies the format
"Assisted-by: AGENT_NAME:MODEL_VERSION". Could you replace
"Assisted-by: LLM" with the tool and model version used? If it was
the same as v1, you could restore its Assisted-by tag.

Reviewed-by: Xin Wang <x.wang@intel.com>
> Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
> ---
> Cc: Arvind Yadav <arvind.yadav@intel.com>
> Cc: Matthew Brost <matthew.brost@intel.com>
> Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> ---
>   drivers/gpu/drm/xe/xe_vm_madvise.c | 6 ------
>   1 file changed, 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/xe/xe_vm_madvise.c b/drivers/gpu/drm/xe/xe_vm_madvise.c
> index 0474768a38aa..5c7aefc641ee 100644
> --- a/drivers/gpu/drm/xe/xe_vm_madvise.c
> +++ b/drivers/gpu/drm/xe/xe_vm_madvise.c
> @@ -713,12 +713,6 @@ int xe_vm_madvise_ioctl(struct drm_device *dev, void *data, struct drm_file *fil
>   
>   	attr_type = array_index_nospec(args->type, ARRAY_SIZE(madvise_funcs));
>   
> -	/* Ensure the madvise function exists for this type */
> -	if (!madvise_funcs[attr_type]) {
> -		err = -EINVAL;
> -		goto err_fini;
> -	}
> -
>   	madvise_funcs[attr_type](xe, vm, madvise_range.vmas, madvise_range.num_vmas, args,
>   				 &details);
>