On 2024/8/26 20:23, Zijun Hu wrote:
> From: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
>
> drivers_probe_store() regards bus_rescan_devices_helper()'s returned
> value 0 as success when find driver for a single device user specify
> that is wrong since the following 3 failed cases also return 0:
>
> (1) the device is dead
> (2) bus fails to match() the device with any its driver
> (3) bus fails to probe() the device with any its driver
>
> Fixed by only regarding successfully attaching the device to a driver
> as success.
>
> Fixes: b8c5cec23d5c ("Driver core: udev triggered device-<>driver binding")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Zijun Hu <quic_zijuhu@xxxxxxxxxxx>
> ---
> drivers/base/bus.c | 23 ++++++++++++++++++++++-
> 1 file changed, 22 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/base/bus.c b/drivers/base/bus.c
> index abf090ace833..0a994e63785c 100644
> --- a/drivers/base/bus.c
> +++ b/drivers/base/bus.c
> @@ -40,6 +40,20 @@ static struct kset *bus_kset;
> struct driver_attribute driver_attr_##_name = \
> __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
>
> +/* Bus rescans drivers for a single device */
> +static int __must_check bus_rescan_single_device(struct device *dev)
> +{
> + int ret;
> +
> + if (dev->parent && dev->bus->need_parent_lock)
> + device_lock(dev->parent);
> + ret = device_attach(dev);
> + if (dev->parent && dev->bus->need_parent_lock)
> + device_unlock(dev->parent);
> +
> + return ret;
> +}
> +
> static int __must_check bus_rescan_devices_helper(struct device *dev,
> void *data);
>
> @@ -311,12 +325,19 @@ static ssize_t drivers_probe_store(const struct bus_type *bus,
> {
> struct device *dev;
> int err = -EINVAL;
> + int res;
>
> dev = bus_find_device_by_name(bus, NULL, buf);
> if (!dev)
> return -ENODEV;
> - if (bus_rescan_devices_helper(dev, NULL) == 0)
> +
> + res = bus_rescan_single_device(dev);
> + /* Propagate error code upwards as far as possible */
> + if (res < 0)
> + err = res;
> + else if (res == 1)
> err = count;
> +
> put_device(dev);
> return err;
> }
>
please ignore RFC for this patch, will push it within a patch
series.
thanks
> ---
> base-commit: 888f67e621dda5c2804a696524e28d0ca4cf0a80
> change-id: 20240826-fix_drivers_probe-88c6a2cc1899
>
> Best regards,
