On Tue, Mar 08, 2022 at 10:17:42PM +0530, Balasubramani Vivekanandan wrote:
This patch is continuation of the effort to move all pointers in i915, which at any point may be pointing to device memory or system memory, to iosys_map interface. More details about the need of this change is explained in the patch series which initiated this task https://patchwork.freedesktop.org/series/99711/ This patch converts all access to the lrc_desc through iosys_map interfaces. Cc: Lucas De Marchi <lucas.demarchi@xxxxxxxxx> Cc: John Harrison <John.C.Harrison@xxxxxxxxx> Cc: Matthew Brost <matthew.brost@xxxxxxxxx> Cc: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx> Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@xxxxxxxxx> ---
...
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc.h b/drivers/gpu/drm/i915/gt/uc/intel_guc.h @@ -2245,13 +2256,13 @@ static void prepare_context_registration_info(struct intel_context *ce) GEM_BUG_ON(i915_gem_object_is_lmem(guc->ct.vma->obj) != i915_gem_object_is_lmem(ce->ring->vma->obj)); - desc = __get_lrc_desc(guc, ctx_id); - desc->engine_class = engine_class_to_guc_class(engine->class); - desc->engine_submit_mask = engine->logical_mask; - desc->hw_context_desc = ce->lrc.lrca; - desc->priority = ce->guc_state.prio; - desc->context_flags = CONTEXT_REGISTRATION_FLAG_KMD; - guc_context_policy_init(engine, desc); + memset(&desc, 0, sizeof(desc));
previously we would re-use whatever was left in guc->lrc_desc_pool_vaddr. Here we are changing it to always zero everything and set the fields we are interested in. As I'm not too familiar with this part and I see us traversing child guc_process_desc which may point to the same id, it doesn't _feel_ safe. Did you check if this is not zero'ing what it shouldn't? Matt Brost / John / Daniele, could you clarify? thanks Lucas De Marchi
