Re: [PATCH for-5.8 2/2] usb: dwc3: meson-g12a: fix USB2 PHY initialization on G12A and A1 SoCs

From: Neil Armstrong <narmstrong@baylibre.com>
To: balbi@kernel.org, gregkh@linuxfoundation.org
Cc: hanjie.lin@amlogic.com, "kernelci.org bot" <bot@kernelci.org>,
	Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
	linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
	yue.wang@amlogic.com, linux-amlogic@lists.infradead.org,
	linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH for-5.8 2/2] usb: dwc3: meson-g12a: fix USB2 PHY initialization on G12A and A1 SoCs
Date: Wed, 27 May 2020 10:17:31 +0200	[thread overview]
Message-ID: <40a874eb-1a2b-533e-ee3e-bd90510abaf9@baylibre.com> (raw)
In-Reply-To: <20200526202943.715220-3-martin.blumenstingl@googlemail.com>

Hi Martin,

On 26/05/2020 22:29, Martin Blumenstingl wrote:
> dwc3_meson_g12a_usb2_init_phy() crashes with NULL pointer on an SM1
> board (which uses the same USB setup as G12A) dereference as reported
> by the Kernel CI bot. This is because of the following call flow:
>   dwc3_meson_g12a_probe
>     priv->drvdata->setup_regmaps
>       dwc3_meson_g12a_setup_regmaps
>         priv->usb2_ports is still 0 so priv->u2p_regmap[i] will be NULL
>     dwc3_meson_g12a_get_phys
>       initializes priv->usb2_ports
>     priv->drvdata->usb_init
>       dwc3_meson_g12a_usb_init
>         dwc3_meson_g12a_usb_init_glue
>           dwc3_meson_g12a_usb2_init
>             priv->drvdata->usb2_init_phy
>               dwc3_meson_g12a_usb2_init_phy
>                 dereferences priv->u2p_regmap[i]
> 
> Call priv->drvdata->setup_regmaps only after dwc3_meson_g12a_get_phys so
> priv->usb2_ports is initialized and the regmaps will be set up
> correctly. This fixes the NULL dereference later on.
> 
> Fixes: 013af227f58a97 ("usb: dwc3: meson-g12a: handle the phy and glue registers separately")
> Reported-by: "kernelci.org bot" <bot@kernelci.org>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
> ---
>  drivers/usb/dwc3/dwc3-meson-g12a.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-meson-g12a.c b/drivers/usb/dwc3/dwc3-meson-g12a.c
> index ce5388338389..1f7f4d88ed9d 100644
> --- a/drivers/usb/dwc3/dwc3-meson-g12a.c
> +++ b/drivers/usb/dwc3/dwc3-meson-g12a.c

[...]

Fixes regression reported at [1] on SEI510 board based on Amlogic G12A.

Felipe, Greg, can this be queued on uxb-next for 5.8 ?

Acked-by: Neil Armstrong <narmstron@baylibre.com>

Thanks,
Neil

[1] http://lore.kernel.org/r/ffe2c64c-62ed-9b59-3754-7ede0f0203be@collabora.com

_______________________________________________
linux-amlogic mailing list
linux-amlogic@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-amlogic