On Wed, Aug 10, 2022 at 05:17:56PM +0200, Andrew Lunn wrote: > > > I guess you are new to the netdev list :-) > > > > > > This is one of those FAQ sort of things, discussed every > > > year. Anything like this is always NACKed. I don't see why this time > > > should be any different. > > > > > > DSA is somewhat special because it is very old. It comes from before > > > the times of DT. Its DT binding was proposed relatively earl in DT > > > times, and would be rejected in modern days. But the rules of ABI mean > > > the label property will be valid forever. But i very much doubt it > > > will spread to interfaces in general. > > > > And if this is a FAQ maybe you can point to a summary (perhaps in > > previous mail discusssion) that explains how to provide stable interface > > names for Ethernet devices on a DT based platform? > > As far so the kernel is concerned, interface names are unstable. They > have never been truly stable, but they have got more unstable in the > past decade with multiple busses being probed in parallel, which did > not happen before so much. > > > On x86 there is a name derived from the device location in the bus > > topology > > This is nothing to do with x86. That is userspace, e.g. systemd, > renaming the interfaces. This applies for any architecture for which > systemd runs on. > > > which may be somewhat stable but it is not clear that it > > cannot change, and there is an optional BIOS provided table that can > > asssign meaningful names to the interfaces. > > I doubt the kernel is looking at ACPI tables. It is user space which > does that. > > The kernel provides udev with a bunch of information about the > interface, its bus location, MAC address, etc. Userspace can then > decide what it wants to call it, and what its alternative names are, > etc. > > Also, this is not just a network interface name problem. Any device > with a number/letter in it is unstable. I2C bus devices: i2c0, > i2c1... SPI bus deviceS: spi0, spi1..., Thees do have numbered aliases in the DT. I don't know if the kernel uses them for anything. > Block devices, sda, sdb, sdc, These too, at least mmc. Thanks Michal
