drm/i915: clear the gpu reloc batch

BugLink: https://bugs.launchpad.net/bugs/1913486
commit 641382e9b44fba81a0778e1914ee35b8471121f9 upstream.

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
(cherry picked from commit 26ebc511e799f621357982ccc37a7987a56a00f4)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: William Breathitt Gray <william.gray@canonical.com>

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 7f7d59445faedbb4a6941691dd156111a8296053..198a91c7653143e023dbb30fa47e9e7ae78616b5 100644 (file)
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -936,7 +936,7 @@ static void reloc_gpu_flush(struct reloc_cache *cache)
        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);
@@ -1163,6 +1163,8 @@ static int __reloc_gpu_alloc(struct i915_execbuffer *eb,
                goto out_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);