On Mon, May 06, 2019 at 02:23:17PM +0000, Jason Gunthorpe wrote: > On Mon, May 06, 2019 at 05:06:06PM +0300, Leon Romanovsky wrote: > > On Mon, May 06, 2019 at 04:45:34PM +0300, Gal Pressman wrote: > > > 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 > > > >>> +++ 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.. > > > > It makes sense, but I'm not certain either. > > The dev_id == dev_port thing makes no sense to me since the driver > always sets them equal on startup - is there some way for these values > to change outside the driver's control? I did some grepping to answer to this question and didn't find anything. Thanks > > Jason
