Re: [PATCH] drm/xe: Fix stolen size check to allow equal WOPCM size

[Matthew Auld <matthew.auld@intel.com>]

On 16/10/2025 23:55, Shuicheng Lin wrote:
> On some platforms without dedicated stolen memory, the calculated
> stolen size may be exactly equal to the WOPCM size. The current
> assertion incorrectly requires it to be strictly greater, causing
> a false failure. Relax the check to allow equality.
> 
> Fixes: 65369b8e2961 ("drm/xe: Change return type of detect_bar2_dgfx() from s64 to u64")
> Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6359
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>

Looking at the logs for PVC it has previously never been probed with an 
actual usable stolen area it seems, so this looks correct to me.

Reviewed-by: Matthew Auld <matthew.auld@intel.com>

> ---
>   drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c b/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c
> index e368b2a36bac..1bddecfb723a 100644
> --- a/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c
> +++ b/drivers/gpu/drm/xe/xe_ttm_stolen_mgr.c
> @@ -106,7 +106,7 @@ static u64 detect_bar2_dgfx(struct xe_device *xe, struct xe_ttm_stolen_mgr *mgr)
>   
>   	stolen_size = tile_size - mgr->stolen_base;
>   
> -	xe_assert(xe, stolen_size > wopcm_size);
> +	xe_assert(xe, stolen_size >= wopcm_size);
>   	stolen_size -= wopcm_size;
>   
>   	/* Verify usage fits in the actual resource available */