> -----Original Message-----
> From: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> Sent: Tuesday, December 8, 2020 12:35 AM
> To: Krzysztof Kozlowski <krzk@xxxxxxxxxx>; linux-arm-
> kernel@xxxxxxxxxxxxxxxxxxx; linux-samsung-soc@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Cc: Sylwester Nawrocki <snawrocki@xxxxxxxxxx>; Marek Szyprowski
> <m.szyprowski@xxxxxxxxxxx>; Bartlomiej Zolnierkiewicz
> <b.zolnierkie@xxxxxxxxxxx>; Arnd Bergmann <arnd@xxxxxxxx>; Chanwoo
> Choi <cw00.choi@xxxxxxxxxxx>; Alim Akhtar <alim.akhtar@xxxxxxxxxxx>;
> Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx>; stable@xxxxxxxxxxxxxxx
> Subject: [PATCH v2 2/4] soc: samsung: exynos-asv: handle reading revision
> register error
>
> If regmap_read() fails, the product_id local variable will contain random
value
> from the stack. Do not try to parse such value and fail the ASV driver
probe.
>
> Fixes: 5ea428595cc5 ("soc: samsung: Add Exynos Adaptive Supply Voltage
> driver")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
> ---
> drivers/soc/samsung/exynos-asv.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/soc/samsung/exynos-asv.c
> b/drivers/soc/samsung/exynos-asv.c
> index f653e3533f0f..5daeadc36382 100644
> --- a/drivers/soc/samsung/exynos-asv.c
> +++ b/drivers/soc/samsung/exynos-asv.c
> @@ -129,7 +129,13 @@ static int exynos_asv_probe(struct platform_device
> *pdev)
> return PTR_ERR(asv->chipid_regmap);
> }
>
> - regmap_read(asv->chipid_regmap, EXYNOS_CHIPID_REG_PRO_ID,
> &product_id);
> + ret = regmap_read(asv->chipid_regmap,
> EXYNOS_CHIPID_REG_PRO_ID,
> + &product_id);
> + if (ret < 0) {
> + dev_err(&pdev->dev, "Cannot read revision from
> ChipID: %d\n",
> + ret);
> + return -ENODEV;
> + }
>
> switch (product_id & EXYNOS_MASK) {
> case 0xE5422000:
> --
> 2.25.1
Reviewed-by: Pankaj Dubey <pankaj.dubey@xxxxxxxxxxx>
