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            <b><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Screen flickering"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=93892#c3">Comment # 3</a>
              on <a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Screen flickering"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=93892">bug 93892</a>
              from <span class="vcard"><a class="email" href="mailto:chris@chris-wilson.co.uk" title="Chris Wilson <chris@chris-wilson.co.uk>"> <span class="fn">Chris Wilson</span></a>
</span></b>
        <pre>It looks like either a missing write flag or invalid mocs used; either of those
would be a userspace bug. A quick test would be to

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 8fd00d279447..423e72830733 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1106,7 +1106,7 @@ i915_gem_execbuffer_move_to_active(struct list_head
*vmas,
                u32 old_write = obj->base.write_domain;

                obj->dirty = 1; /* be paranoid  */
-               obj->base.write_domain = obj->base.pending_write_domain;
+               obj->base.write_domain = I915_GEM_DOMAIN_RENDER;
                if (obj->base.write_domain == 0)
                        obj->base.pending_read_domains |=
obj->base.read_domains;
                obj->base.read_domains = obj->base.pending_read_domains;</pre>
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