drm/i915: clear the gpu reloc batch

The reloc batch is short lived but can exist in the user visible ppGTT,
and since it's backed by an internal object, which lacks page clearing,
we should take care to clear it upfront.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20201224151358.401345-2-matthew.auld@intel.com
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 0cf9e79..19eeb3f 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -1045,7 +1045,7 @@ static void reloc_gpu_flush(struct i915_execbuffer *eb, struct reloc_cache *cach
        GEM_BUG_ON(cache->rq_size >= obj->base.size / sizeof(u32));
        cache->rq_cmd[cache->rq_size] = MI_BATCH_BUFFER_END;
 
-       __i915_gem_object_flush_map(obj, 0, sizeof(u32) * (cache->rq_size + 1));
+       i915_gem_object_flush_map(obj);
        i915_gem_object_unpin_map(obj);
 
        intel_gt_chipset_flush(cache->rq->engine->gt);
@@ -1295,6 +1295,8 @@ static int __reloc_gpu_alloc(struct i915_execbuffer *eb,
                goto err_pool;
        }
 
+       memset32(cmd, 0, pool->obj->base.size / sizeof(u32));
+
        batch = i915_vma_instance(pool->obj, vma->vm, NULL);
        if (IS_ERR(batch)) {
                err = PTR_ERR(batch);