linux-kernel - Re: [PATCH v4 05/11] PCI: Use driver_set

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]
Message-ID: <CAHp75VfLtjfrB4Zj9ncOg3VYQrX58chEL+6g31_5fwuMUuURPg@mail.gmail.com>
Date:   Tue, 15 Mar 2022 20:01:18 +0200
From:   Andy Shevchenko <andy.shevchenko@...il.com>
To:     Krzysztof Kozlowski <krzysztof.kozlowski@...onical.com>
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Stuart Yoder <stuyoder@...il.com>,
        Laurentiu Tudor <laurentiu.tudor@....com>,
        Abel Vesa <abel.vesa@....com>, Shawn Guo <shawnguo@...nel.org>,
        Sascha Hauer <s.hauer@...gutronix.de>,
        Fabio Estevam <festevam@...il.com>,
        "K. Y. Srinivasan" <kys@...rosoft.com>,
        Haiyang Zhang <haiyangz@...rosoft.com>,
        Stephen Hemminger <sthemmin@...rosoft.com>,
        Wei Liu <wei.liu@...nel.org>, Dexuan Cui <decui@...rosoft.com>,
        Bjorn Helgaas <bhelgaas@...gle.com>,
        Bjorn Andersson <bjorn.andersson@...aro.org>,
        Mathieu Poirier <mathieu.poirier@...aro.org>,
        Vineeth Vijayan <vneethv@...ux.ibm.com>,
        Peter Oberparleiter <oberpar@...ux.ibm.com>,
        Heiko Carstens <hca@...ux.ibm.com>,
        Vasily Gorbik <gor@...ux.ibm.com>,
        Alexander Gordeev <agordeev@...ux.ibm.com>,
        Christian Borntraeger <borntraeger@...ux.ibm.com>,
        Sven Schnelle <svens@...ux.ibm.com>,
        Andy Gross <agross@...nel.org>,
        Srinivas Kandagatla <srinivas.kandagatla@...aro.org>,
        Mark Brown <broonie@...nel.org>,
        "Michael S. Tsirkin" <mst@...hat.com>,
        Jason Wang <jasowang@...hat.com>,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        linux-clk <linux-clk@...r.kernel.org>,
        NXP Linux Team <linux-imx@....com>,
        linux-arm Mailing List <linux-arm-kernel@...ts.infradead.org>,
        Linux on Hyper-V List <linux-hyperv@...r.kernel.org>,
        linux-pci <linux-pci@...r.kernel.org>,
        linux-remoteproc@...r.kernel.org, linux-s390@...r.kernel.org,
        linux-arm-msm@...r.kernel.org,
        ALSA Development Mailing List <alsa-devel@...a-project.org>,
        linux-spi <linux-spi@...r.kernel.org>,
        virtualization@...ts.linux-foundation.org,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Rasmus Villemoes <linux@...musvillemoes.dk>
Subject: Re: [PATCH v4 05/11] PCI: Use driver_set_override() instead of open-coding

On Sat, Mar 12, 2022 at 4:09 PM Krzysztof Kozlowski
<krzysztof.kozlowski@...onical.com> wrote:
>
> Use a helper to set driver_override to reduce amount of duplicated code.

the amount

> Make the driver_override field const char, because it is not modified by
> the core and it matches other subsystems.


Seems like mine #4 here
https://gist.github.com/andy-shev/a2cb1ee4767d6d2f5d20db53ecb9aabc :-)
Reviewed-by: Andy Shevchenko <andy.shevchenko@...il.com>
Thanks!

> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@...onical.com>
> Acked-by: Bjorn Helgaas <bhelgaas@...gle.com>
> ---
>  drivers/pci/pci-sysfs.c | 28 ++++------------------------
>  include/linux/pci.h     |  6 +++++-
>  2 files changed, 9 insertions(+), 25 deletions(-)
>
> diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c
> index 602f0fb0b007..5c42965c32c2 100644
> --- a/drivers/pci/pci-sysfs.c
> +++ b/drivers/pci/pci-sysfs.c
> @@ -567,31 +567,11 @@ static ssize_t driver_override_store(struct device *dev,
>                                      const char *buf, size_t count)
>  {
>         struct pci_dev *pdev = to_pci_dev(dev);
> -       char *driver_override, *old, *cp;
> -
> -       /* We need to keep extra room for a newline */
> -       if (count >= (PAGE_SIZE - 1))
> -               return -EINVAL;
> -
> -       driver_override = kstrndup(buf, count, GFP_KERNEL);
> -       if (!driver_override)
> -               return -ENOMEM;
> -
> -       cp = strchr(driver_override, '\n');
> -       if (cp)
> -               *cp = '\0';
> -
> -       device_lock(dev);
> -       old = pdev->driver_override;
> -       if (strlen(driver_override)) {
> -               pdev->driver_override = driver_override;
> -       } else {
> -               kfree(driver_override);
> -               pdev->driver_override = NULL;
> -       }
> -       device_unlock(dev);
> +       int ret;
>
> -       kfree(old);
> +       ret = driver_set_override(dev, &pdev->driver_override, buf, count);
> +       if (ret)
> +               return ret;
>
>         return count;
>  }
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 60d423d8f0c4..415491fb85f4 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -516,7 +516,11 @@ struct pci_dev {
>         u16             acs_cap;        /* ACS Capability offset */
>         phys_addr_t     rom;            /* Physical address if not from BAR */
>         size_t          romlen;         /* Length if not from BAR */
> -       char            *driver_override; /* Driver name to force a match */
> +       /*
> +        * Driver name to force a match.  Do not set directly, because core
> +        * frees it.  Use driver_set_override() to set or clear it.
> +        */
> +       const char      *driver_override;
>
>         unsigned long   priv_flags;     /* Private flags for the PCI driver */
>
> --
> 2.32.0
>


-- 
With Best Regards,
Andy Shevchenko