From f6350da41dc728da5a27044bde6f770525ba97d6 Mon Sep 17 00:00:00 2001 From: Arseny Maslennikov Date: Thu, 6 Sep 2018 17:51:12 +0300 Subject: IB/ipoib: Log sysfs 'dev_id' accesses from userspace 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 Signed-off-by: Doug Ledford --- drivers/infiniband/ulp/ipoib/ipoib_main.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'drivers/infiniband/ulp/ipoib/ipoib_main.c') diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c index a046076670e6..1df90f0d9e64 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c @@ -2387,6 +2387,35 @@ 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) { @@ -2428,6 +2457,8 @@ 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)) -- cgit v1.2.3