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From:   Guenter Roeck <groeck@google.com>
Date:   Tue, 11 Oct 2022 08:56:33 -0700
Message-ID: <CABXOdTdum0q=2Fy3yM3OnGmHM9ZkNyEURx6C08879ND7ye=vxg@mail.gmail.com>
Subject: Re: [PATCH] drm/msm: Remove redundant check for 'submit'
To:     Aashish Sharma <shraash@google.com>
Cc:     Guenter Roeck <groeck@chromium.org>,
        Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        Maling list - DRI developers 
        <dri-devel@lists.freedesktop.org>,
        freedreno <freedreno@lists.freedesktop.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        kernel test robot <lkp@intel.com>,
        Dan Carpenter <dan.carpenter@oracle.com>
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On Tue, Oct 11, 2022 at 12:55 AM Aashish Sharma <shraash@google.com> wrote:
>
> Rectify the below smatch warning:
> drivers/gpu/drm/msm/msm_gem_submit.c:963 msm_ioctl_gem_submit() warn:
> variable dereferenced before check 'submit'
>
> 'submit' is normally error pointer or valid, so remove its NULL
> initializer as it's confusing and also remove a redundant check for it's
> value.
>
> Signed-off-by: Aashish Sharma <shraash@google.com>
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>

Reviewed-by: Guenter Roeck <groeck@chromium.org>

> ---
>  drivers/gpu/drm/msm/msm_gem_submit.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/msm_gem_submit.c b/drivers/gpu/drm/msm/msm_gem_submit.c
> index 5599d93ec0d2..74fe1c56cd65 100644
> --- a/drivers/gpu/drm/msm/msm_gem_submit.c
> +++ b/drivers/gpu/drm/msm/msm_gem_submit.c
> @@ -706,7 +706,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
>         struct msm_drm_private *priv = dev->dev_private;
>         struct drm_msm_gem_submit *args = data;
>         struct msm_file_private *ctx = file->driver_priv;
> -       struct msm_gem_submit *submit = NULL;
> +       struct msm_gem_submit *submit;
>         struct msm_gpu *gpu = priv->gpu;
>         struct msm_gpu_submitqueue *queue;
>         struct msm_ringbuffer *ring;
> @@ -946,8 +946,7 @@ int msm_ioctl_gem_submit(struct drm_device *dev, void *data,
>                 put_unused_fd(out_fence_fd);
>         mutex_unlock(&queue->lock);
>  out_post_unlock:
> -       if (submit)
> -               msm_gem_submit_put(submit);
> +       msm_gem_submit_put(submit);
>         if (!IS_ERR_OR_NULL(post_deps)) {
>                 for (i = 0; i < args->nr_out_syncobjs; ++i) {
>                         kfree(post_deps[i].chain);
> --
> 2.38.0.rc2.412.g84df46c1b4-goog
>