On 06-May-19 13:49, Leon Romanovsky wrote: > On Mon, May 06, 2019 at 01:35:07PM +0300, Gal Pressman wrote: >> On 06-May-19 13:21, Leon Romanovsky wrote: >>> From: Leon Romanovsky <leonro@xxxxxxxxxxxx> >>> >>> Systemd triggers the following warning during IPoIB device load: >>> >>> mlx5_core 0000:00:0c.0 ib0: "systemd-udevd" wants to know my dev_id. >>> Should it look at dev_port instead? >>> See Documentation/ABI/testing/sysfs-class-net for more info. >>> >>> This is caused due to user space attempt to differentiate old systems >>> without dev_port and new systems with dev_port. In case dev_port will >>> be zero, the systemd will try to read dev_id instead. >>> >>> There is no need to print a warning in such case, because it is valid >>> situation and it is needed to ensure systemd compatibility with old >>> kernels. >>> >>> Link: https://github.com/systemd/systemd/blob/master/src/udev/udev-builtin-net_id.c#L358 >>> Cc: <stable@xxxxxxxxxxxxxxx> # 4.19 >>> Fixes: f6350da41dc7 ("IB/ipoib: Log sysfs 'dev_id' accesses from userspace") >>> Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> >>> --- >>> drivers/infiniband/ulp/ipoib/ipoib_main.c | 12 +++++++++++- >>> 1 file changed, 11 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c >>> index 48eda16db1a7..34e6495aa8c5 100644 >>> --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c >>> +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c >>> @@ -2402,7 +2402,17 @@ static ssize_t dev_id_show(struct device *dev, >>> { >>> struct net_device *ndev = to_net_dev(dev); >>> >>> - if (ndev->dev_id == ndev->dev_port) >>> + /* >>> + * ndev->dev_port will be equal to 0 in old kernel prior to commit >>> + * 9b8b2a323008 ("IB/ipoib: Use dev_port to expose network interface port numbers") >>> + * Zero was chosen as special case for user space applications to fallback >>> + * and query dev_id to check if it has different value or not. >>> + * >>> + * Don't pring warning in such scenario. >> >> "pring" -> "print". > > Are you ok with other changes and I can add your ROB tag? To my understanding, the test should be for just: if (ndev->dev_port) As if dev_port is set then there's no reason to use dev_id, regardless of its value. But I'm not really familiar with this flow.. >> >>> + * >>> + * https://github.com/systemd/systemd/blob/master/src/udev/udev-builtin-net_id.c#L358 >>> + */ >>> + if (ndev->dev_port && 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); >>> >>
