Re: [PATCH] usb: renesas_usbhs: Fix synchronous external abort on unbind

[Geert Uytterhoeven <geert@linux-m68k.org>]

Hi Claudiu,

On Wed, 22 Oct 2025 at 15:06, Claudiu <claudiu.beznea@tuxon.dev> wrote:
> From: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
>
> A synchronous external abort occurs on the Renesas RZ/G3S SoC if unbind is
> executed after the configuration sequence described above:

[...]

> The issue occurs because usbhs_sys_function_pullup(), which accesses the IP
> registers, is executed after the USBHS clocks have been disabled. The
> problem is reproducible on the Renesas RZ/G3S SoC starting with the
> addition of module stop in the clock enable/disable APIs. With module stop
> functionality enabled, a bus error is expected if a master accesses a
> module whose clock has been stopped and module stop activated.
>
> Disable the IP clocks at the end of remove.
>
> Cc: stable@vger.kernel.org
> Fixes: f1407d5c6624 ("usb: renesas_usbhs: Add Renesas USBHS common code")
> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>

Thanks for your patch!

> --- a/drivers/usb/renesas_usbhs/common.c
> +++ b/drivers/usb/renesas_usbhs/common.c
> @@ -813,18 +813,18 @@ static void usbhs_remove(struct platform_device *pdev)
>
>         flush_delayed_work(&priv->notify_hotplug_work);
>
> -       /* power off */
> -       if (!usbhs_get_dparam(priv, runtime_pwctrl))
> -               usbhsc_power_ctrl(priv, 0);
> -
> -       pm_runtime_disable(&pdev->dev);
> -
>         usbhs_platform_call(priv, hardware_exit, pdev);
>         usbhsc_clk_put(priv);

Shouldn't the usbhsc_clk_put() call be moved just before the
pm_runtime_disable() call, too, cfr. the error path in usbhs_probe()?

>         reset_control_assert(priv->rsts);
>         usbhs_mod_remove(priv);
>         usbhs_fifo_remove(priv);
>         usbhs_pipe_remove(priv);
> +
> +       /* power off */
> +       if (!usbhs_get_dparam(priv, runtime_pwctrl))
> +               usbhsc_power_ctrl(priv, 0);
> +
> +       pm_runtime_disable(&pdev->dev);
>  }
>
>  static int usbhsc_suspend(struct device *dev)

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds