On Tue, Aug 28, 2018 at 03:23:04PM -0600, Jordan Crouse wrote:
> The MDSS device is created before the MSM driver attempts to bind the
> sub components. If any of the components return -EPROBE_DEFER the MDSS
> device is destroyed and tried again later.
>
> If this happens the "dpu_mdss_isr" interrupt created from the DPU MDSS
> is not freed when the MDSS device is destroyed and has a risk of
> triggering later and hitting a fault by accessing a mmio region that
> no longer exists. Even if the interrupt isn't triggered by
> accident when the device attempts to reprobe it would error out
> when it tries to re-register the interrupt so unconditionally removing
> it in the destroy is the right move.
>
> Switch the device managed "dpu_mdss_isr" to be unmanaged and add a
> free_irq() in the mdss destroy function.
>
> Signed-off-by: Jordan Crouse <jcrouse@xxxxxxxxxxxxxx>
Reviewed-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c
> index 9e533b86682c..2235ef8129f4 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_mdss.c
> @@ -158,6 +158,8 @@ static void dpu_mdss_destroy(struct drm_device *dev)
>
> _dpu_mdss_irq_domain_fini(dpu_mdss);
>
> + free_irq(platform_get_irq(pdev, 0), dpu_mdss);
> +
> msm_dss_put_clk(mp->clk_config, mp->num_clk);
> devm_kfree(&pdev->dev, mp->clk_config);
>
> @@ -215,7 +217,7 @@ int dpu_mdss_init(struct drm_device *dev)
> if (ret)
> goto irq_domain_error;
>
> - ret = devm_request_irq(dev->dev, platform_get_irq(pdev, 0),
> + ret = request_irq(platform_get_irq(pdev, 0),
> dpu_mdss_irq, 0, "dpu_mdss_isr", dpu_mdss);
> if (ret) {
> DPU_ERROR("failed to init irq: %d\n", ret);
> --
> 2.18.0
>
--
Sean Paul, Software Engineer, Google / Chromium OS
