Date:   Mon, 13 Mar 2023 22:41:50 +0000
From:   Wei Liu <wei.liu@kernel.org>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-kernel@vger.kernel.org, rafael@kernel.org,
        "David S. Miller" <davem@davemloft.net>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Alex Shi <alexs@kernel.org>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
        Alexandre Bounine <alex.bou9@gmail.com>,
        Alison Schofield <alison.schofield@intel.com>,
        Ben Widawsky <bwidawsk@kernel.org>,
        Bjorn Helgaas <bhelgaas@google.com>,
        Dan Williams <dan.j.williams@intel.com>,
        Dexuan Cui <decui@microsoft.com>,
        Eric Dumazet <edumazet@google.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Hannes Reinecke <hare@suse.de>,
        Harald Freudenberger <freude@linux.ibm.com>,
        Heiko Carstens <hca@linux.ibm.com>,
        Hu Haowen <src.res@email.cn>,
        Ilya Dryomov <idryomov@gmail.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Iwona Winiarska <iwona.winiarska@intel.com>,
        Jakub Kicinski <kuba@kernel.org>, Jens Axboe <axboe@kernel.dk>,
        Jonathan Corbet <corbet@lwn.net>,
        Laurentiu Tudor <laurentiu.tudor@nxp.com>,
        Matt Porter <mporter@kernel.crashing.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Paolo Abeni <pabeni@redhat.com>,
        Stuart Yoder <stuyoder@gmail.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Vishal Verma <vishal.l.verma@intel.com>,
        Wei Liu <wei.liu@kernel.org>,
        Yanteng Si <siyanteng@loongson.cn>
Subject: Re: [PATCH 23/36] driver core: bus: mark the struct bus_type for
 sysfs callbacks as constant
Message-ID: <ZA+mroPKki9/iUkT@liuwe-devbox-debian-v2>
References: <20230313182918.1312597-1-gregkh@linuxfoundation.org>
 <20230313182918.1312597-23-gregkh@linuxfoundation.org>
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In-Reply-To: <20230313182918.1312597-23-gregkh@linuxfoundation.org>
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On Mon, Mar 13, 2023 at 07:29:05PM +0100, Greg Kroah-Hartman wrote:
> struct bus_type should never be modified in a sysfs callback as there is
> nothing in the structure to modify, and frankly, the structure is almost
> never used in a sysfs callback, so mark it as constant to allow struct
> bus_type to be moved to read-only memory.
[...]
> diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c
> index d24dd65b33d4..513adba09f56 100644
> --- a/drivers/hv/vmbus_drv.c
> +++ b/drivers/hv/vmbus_drv.c
> @@ -684,7 +684,7 @@ static const struct attribute_group vmbus_dev_group = {
>  __ATTRIBUTE_GROUPS(vmbus_dev);
>  
>  /* Set up the attribute for /sys/bus/vmbus/hibernation */
> -static ssize_t hibernation_show(struct bus_type *bus, char *buf)
> +static ssize_t hibernation_show(const struct bus_type *bus, char *buf)
>  {
>  	return sprintf(buf, "%d\n", !!hv_is_hibernation_supported());
>  }

Acked-by: Wei Liu <wei.liu@kernel.org>