drm/i915/gem: Serialise debugfs i915_gem_objects with ctx->mutex
Since the debugfs may peek into the GEM contexts as the corresponding client/fd is being closed, we may try and follow a dangling pointer. However, the context closure itself is serialised with the ctx->mutex, so if we hold that mutex as we inspect the state coupled in the context, we know the pointers within the context are stable and will remain valid as we inspect their tables. Signed-off-by:Chris Wilson <chris@chris-wilson.co.uk> Cc: CQ Tang <cq.tang@intel.com> Cc: Daniel Vetter <daniel.vetter@intel.com> Cc: stable@vger.kernel.org Reviewed-by: