[PATCH] drm/i915/ttm: Abort suspend on i915_ttm_backup failure

[Nirmoy Das]

On system suspend when system memory is low then i915_gem_obj_copy_ttm()
could fail trying to backup a lmem obj. GEM_WARN_ON() is not enough,
suspend shouldn't continue if i915_ttm_backup() throws an error.

References: https://gitlab.freedesktop.org/drm/intel/-/issues/6529
Reviewed-by: Matthew Auld <matthew.auld at intel.com>
Suggested-by: Chris P Wilson <chris.p.wilson at intel.com>
Signed-off-by: Nirmoy Das <nirmoy.das at intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
index 9aad84059d56..6f5d5c0909b4 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_pm.c
@@ -79,7 +79,12 @@ static int i915_ttm_backup(struct i915_gem_apply_to_region *apply,
 		goto out_no_populate;
 
 	err = i915_gem_obj_copy_ttm(backup, obj, pm_apply->allow_gpu, false);
-	GEM_WARN_ON(err);
+	if (err) {
+		drm_err(&i915->drm,
+			"Unable to copy from device to system memory, err:%d\n",
+			err);
+		goto out_no_populate;
+	}
 	ttm_bo_wait_ctx(backup_bo, &ctx);
 
 	obj->ttm.backup = backup;
-- 
2.35.1