From 9a940bb52dcb359f639536bed977d837e323a593 Mon Sep 17 00:00:00 2001 From: Tomasz Lis Date: Wed, 22 Oct 2025 00:48:16 +0200 Subject: [PATCH] drm/xe: Assert that VF will never use fixed placement of BOs Most BOs do not care at which offset they will be accessed within GGTT or PPGTT. The few which do care, should be only created on PF, and mapped within GGTT. On VFs, mapping at fixed offset is prohibited, as each VF is granted access to a range of GGTT address space. Since fixed addresses of GGTT mapping can only be used on PF, add an assert which makes sure no attempt of fixed placement will happen for a driver probed on a VF. Reviewed-by: Michal Wajdeczko Cc: Michal Wajdeczko Signed-off-by: Tomasz Lis Signed-off-by: Michal Wajdeczko Link: https://lore.kernel.org/r/20251021224817.1593817-4-tomasz.lis@intel.com --- drivers/gpu/drm/xe/xe_bo.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/xe/xe_bo.c b/drivers/gpu/drm/xe/xe_bo.c index 66ed888bba076..ad0da473ee652 100644 --- a/drivers/gpu/drm/xe/xe_bo.c +++ b/drivers/gpu/drm/xe/xe_bo.c @@ -2275,6 +2275,12 @@ static int __xe_bo_fixed_placement(struct xe_device *xe, struct ttm_place *place = bo->placements; u32 vram_flag, vram_stolen_flags; + /* + * to allow fixed placement in GGTT of a VF, post-migration fixups would have to + * include selecting a new fixed offset and shifting the page ranges for it + */ + xe_assert(xe, !IS_SRIOV_VF(xe) || !(bo->flags & XE_BO_FLAG_GGTT)); + if (flags & (XE_BO_FLAG_USER | XE_BO_FLAG_SYSTEM)) return -EINVAL; -- 2.47.3