Re: [PATCH] drm/i915/gvt: fix uninitialized return in intel_gvt_update_reg_whitelist()

From: Chris Wilson
Date: Mon Jan 25 2021 - 04:53:50 EST


Quoting Dan Carpenter (2021-01-25 08:48:30)
> Smatch found an uninitialized variable bug in this code:
>
> drivers/gpu/drm/i915/gvt/cmd_parser.c:3191 intel_gvt_update_reg_whitelist()
> error: uninitialized symbol 'ret'.
>
> The first thing that Smatch complains about is that "ret" isn't set if
> we don't enter the "for_each_engine(engine, &dev_priv->gt, id) {" loop.
> Presumably we always have at least one engine so that's a false
> positive.
>
> But it's definitely a bug to not set "ret" if i915_gem_object_pin_map()
> fails.

True.

> Let's fix the bug and silence the false positive.
>
> Fixes: 493f30cd086e ("drm/i915/gvt: parse init context to update cmd accessible reg whitelist")
> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx>
-Chris