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From:   "Rafael J. Wysocki" <rafael@kernel.org>
Date:   Fri, 21 Aug 2020 20:28:41 +0200
Message-ID: <CAJZ5v0h3vFLyY9AXYFvcJD3agYk7RFCyzkWefDk_9bvCE09RNg@mail.gmail.com>
Subject: Re: [PATCH] drivers: acpi: apd: Check return value of acpi_dev_get_property
To:     Furquan Shaikh <furquan@google.com>
Cc:     "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Len Brown <lenb@kernel.org>, Aaron Durbin <adurbin@google.com>,
        "Agrawal, Akshu" <akshu.agrawal@amd.com>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Wed, Aug 19, 2020 at 7:17 PM Furquan Shaikh <furquan@google.com> wrote:
>
> `fch_misc_setup()` uses `acpi_dev_get_property()` to read the value of
> "is-rv" passed in by BIOS in ACPI tables. However, not all BIOSes
> might pass in this property and hence it is important to first check
> the return value of `acpi_dev_get_property()` before referencing the
> object filled by it.
>
> Signed-off-by: Furquan Shaikh <furquan@google.com>
> ---
>  drivers/acpi/acpi_apd.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/acpi/acpi_apd.c b/drivers/acpi/acpi_apd.c
> index 4c348377a39d..806b8ce05624 100644
> --- a/drivers/acpi/acpi_apd.c
> +++ b/drivers/acpi/acpi_apd.c
> @@ -99,8 +99,8 @@ static int fch_misc_setup(struct apd_private_data *pdata)
>         if (ret < 0)
>                 return -ENOENT;
>
> -       acpi_dev_get_property(adev, "is-rv", ACPI_TYPE_INTEGER, &obj);
> -       clk_data->is_rv = obj->integer.value;
> +       if (!acpi_dev_get_property(adev, "is-rv", ACPI_TYPE_INTEGER, &obj))
> +               clk_data->is_rv = obj->integer.value;
>
>         list_for_each_entry(rentry, &resource_list, node) {
>                 clk_data->base = devm_ioremap(&adev->dev, rentry->res->start,
> --

Applied (with minor subject edits) as 5.9-rc material, thanks!