Some tools may currently be using only the deprecated attribute; let's print an elaborate and clear deprecation notice to kmsg. To do that, we have to replace the whole sysfs file, since we inherit the original one from netdev. Signed-off-by: Arseny Maslennikov <ar@xxxxxxxxx> --- drivers/infiniband/ulp/ipoib/ipoib_main.c | 31 +++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c index 30f840f874b3..74732726ec6f 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c @@ -2386,6 +2386,35 @@ int ipoib_add_pkey_attr(struct net_device *dev) return device_create_file(&dev->dev, &dev_attr_pkey); } +/* + * We erroneously exposed the iface's port number in the dev_id + * sysfs field long after dev_port was introduced for that purpose[1], + * and we need to stop everyone from relying on that. + * Let's overload the shower routine for the dev_id file here + * to gently bring the issue up. + * + * [1] https://www.spinics.net/lists/netdev/msg272123.html + */ +static ssize_t dev_id_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct net_device *ndev = to_net_dev(dev); + + if (ndev->dev_id == ndev->dev_port) + netdev_info_once(ndev, + "\"%s\" wants to know my dev_id. Should it look at dev_port instead? See Documentation/ABI/testing/sysfs-class-net for more info.\n", + current->comm); + + return sprintf(buf, "%#x\n", ndev->dev_id); +} +static DEVICE_ATTR_RO(dev_id); + +int ipoib_intercept_dev_id_attr(struct net_device *dev) +{ + device_remove_file(&dev->dev, &dev_attr_dev_id); + return device_create_file(&dev->dev, &dev_attr_dev_id); +} + static struct net_device *ipoib_add_port(const char *format, struct ib_device *hca, u8 port) { @@ -2427,6 +2456,8 @@ static struct net_device *ipoib_add_port(const char *format, */ ndev->priv_destructor = ipoib_intf_free; + if (ipoib_intercept_dev_id_attr(ndev)) + goto sysfs_failed; if (ipoib_cm_add_mode_attr(ndev)) goto sysfs_failed; if (ipoib_add_pkey_attr(ndev)) -- 2.19.0.rc2
