linux-kernel - Re: [PATCH 1/2] PM / devfreq: rk3399_dmc: Add missing devfreq_event_disable

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 23 Dec 2019 01:49:00 +0900
From:   Chanwoo Choi <chanwoo@...nel.org>
To:     Yangtao Li <tiny.windzz@...il.com>
Cc:     Chanwoo Choi <cw00.choi@...sung.com>,
        MyungJoo Ham <myungjoo.ham@...sung.com>,
        Kyungmin Park <kyungmin.park@...sung.com>,
        Kukjin Kim <kgene@...nel.org>,
        Krzysztof Kozlowski <krzk@...nel.org>,
        Linux PM list <linux-pm@...r.kernel.org>,
        linux-samsung-soc <linux-samsung-soc@...r.kernel.org>,
        linux-arm-kernel <linux-arm-kernel@...ts.infradead.org>,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 1/2] PM / devfreq: rk3399_dmc: Add missing devfreq_event_disable_edev

Hi,

2019년 12월 22일 (일) 오전 3:21, Yangtao Li <tiny.windzz@...il.com>님이 작성:
>
> The probe process may fail, but the devfreq event device remains
> enabled. Call devfreq_event_disable_edev on the error return path.
>
> Signed-off-by: Yangtao Li <tiny.windzz@...il.com>
> ---
>  drivers/devfreq/rk3399_dmc.c | 17 ++++++++++++-----
>  1 file changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
> index 2f1027c5b647..4f4e7c041888 100644
> --- a/drivers/devfreq/rk3399_dmc.c
> +++ b/drivers/devfreq/rk3399_dmc.c
> @@ -364,7 +364,8 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
>                         if (res.a0) {
>                                 dev_err(dev, "Failed to set dram param: %ld\n",
>                                         res.a0);
> -                               return -EINVAL;
> +                               ret = -EINVAL;
> +                               goto err_disable_edev;

After jumping err_disable_edev, it calls the dev_pm_opp_of_remove_table().
it is wrong. It doesn't need to remove the table.

>                         }
>                 }
>         }
> @@ -373,8 +374,10 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
>         if (node) {
>                 data->regmap_pmu = syscon_node_to_regmap(node);
>                 of_node_put(node);
> -               if (IS_ERR(data->regmap_pmu))
> -                       return PTR_ERR(data->regmap_pmu);
> +               if (IS_ERR(data->regmap_pmu)) {
> +                       ret = PTR_ERR(data->regmap_pmu);
> +                       goto err_disable_edev;

ditto.

After jumping err_disable_edev, it calls the dev_pm_opp_of_remove_table().
it is wrong. It doesn't need to remove the table.

> +               }
>         }
>
>         regmap_read(data->regmap_pmu, RK3399_PMUGRF_OS_REG2, &val);
> @@ -392,7 +395,8 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
>                 data->odt_dis_freq = data->timing.lpddr4_odt_dis_freq;
>                 break;
>         default:
> -               return -EINVAL;
> +               ret = -EINVAL;
> +               goto err_disable_edev;

ditto.

>         };
>
>         arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
> @@ -426,7 +430,8 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
>          */
>         if (dev_pm_opp_of_add_table(dev)) {
>                 dev_err(dev, "Invalid operating-points in device tree.\n");
> -               return -EINVAL;
> +               ret = -EINVAL;
> +               goto err_disable_edev;

ditto.

>         }
>
>         of_property_read_u32(np, "upthreshold",
> @@ -464,6 +469,8 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
>
>         return 0;
>
> +err_disable_edev:
> +       devfreq_event_disable_edev(data->edev);

It is wrong. It have to be called under dev_pm_opp_of_remove_table().
It ignores the sequence of exception handling.

>  err_free_opp:
>         dev_pm_opp_of_remove_table(&pdev->dev);
>         return ret;
> --
> 2.17.1
>


-- 
Best Regards,
Chanwoo Choi