Re: [PATCH v4 1/4] drm/xe: Don't abort the shrinker walk on -EBUSY

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

On Fri, Oct 16, 2026 at 03:35:20PM +0200, Thomas Hellström wrote:
> xe_bo_shrink() returns -EBUSY for bos that can't currently be shrunk,
> for example imported dma-bufs, bos whose vm is currently validating,
> bos that are still busy after the wait timeout, or bos whose backup
> fails. The shrinker LRU walk treats any negative return value as
> fatal and aborts, which also skips the remaining shrinker passes.
> 
> As a result, a single such bo, like an imported dma-buf on the
> XE_PL_TT LRU, prevents reclaim of all bos behind it on the LRU.
> 
> Skip bos for which xe_bo_shrink() returns -EBUSY and continue the
> walk, like the TTM LRU walk does.
> 
> v4:
> - Patch introduced.
> 
> Fixes: 00c8efc3180f ("drm/xe: Add a shrinker for xe bos")
> Cc: Christian König <christian.koenig@amd.com>
> Cc: Matthew Brost <matthew.brost@intel.com>

I noticed this on as well.

Reviewed-by: Matthew Brost <matthew.brost@intel.com>`

> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: intel-xe@lists.freedesktop.org
> Cc: <stable@vger.kernel.org> # v6.15+
> Assisted-by: LLM
> Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
> ---
>  drivers/gpu/drm/xe/xe_shrinker.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/gpu/drm/xe/xe_shrinker.c b/drivers/gpu/drm/xe/xe_shrinker.c
> index deb4378c1ec1..4e4da76936f4 100644
> --- a/drivers/gpu/drm/xe/xe_shrinker.c
> +++ b/drivers/gpu/drm/xe/xe_shrinker.c
> @@ -113,6 +113,9 @@ static int __xe_shrinker_walk(struct xe_shrinker *shrinker,
>  				continue;
>  
>  			lret = xe_bo_shrink(ctx, ttm_bo, flags, scanned);
> +			/* Like the TTM LRU walk, skip bos we can't shrink now. */
> +			if (lret == -EBUSY)
> +				continue;
>  			if (lret < 0) {
>  				ret = lret;
>  				goto out;
> -- 
> 2.56.0
>