Re: [PATCH v2 3/4] drm/msm: Fix debugfs deadlock

[Doug Anderson]

Hi,

On Wed, Mar 31, 2021 at 6:24 PM Rob Clark <robdclark@xxxxxxxxx> wrote:
>
> From: Rob Clark <robdclark@xxxxxxxxxxxx>
>
> In normal cases the gem obj lock is acquired first before mm_lock.  The
> exception is iterating the various object lists.  In the shrinker path,
> deadlock is avoided by using msm_gem_trylock() and skipping over objects
> that cannot be locked.  But for debugfs the straightforward thing is to
> split things out into a separate list of all objects protected by it's
> own lock.
>
> Fixes: d984457b31c4 ("drm/msm: Add priv->mm_lock to protect active/inactive lists")
> Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
> Tested-by: Douglas Anderson <dianders@xxxxxxxxxxxx>

Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx>