Avoid exposing a partially constructed context by deferring the
list_add() from the initial construction to the end of registration.
Otherwise, if we peek into the list of contexts from inside debugfs, we
may see the partially constructed context and chase down some dangling
incomplete pointers.
Reported-by: NCQ Tang <cq.tang@intel.com>
Fixes: 3aa9945a ("drm/i915: Separate GEM context construction and registration to userspace")
References: f6e8aa38 ("drm/i915: Report the number of closed vma held by each context in debugfs")
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: CQ Tang <cq.tang@intel.com>
Cc: <stable@vger.kernel.org> # v5.2+
Reviewed-by: NMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200730092856.23615-1-chris@chris-wilson.co.ukSigned-off-by: NRodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: NJoonas Lahtinen <joonas.lahtinen@linux.intel.com>
(cherry picked from commit eb4dedae)
Signed-off-by: NJani Nikula <jani.nikula@intel.com>