Re: [PATCH v1 1/1] Revert "pinctrl: avoid unsafe code pattern in find_pinctrl()"

[Andy Shevchenko]

On Tue, Oct 17, 2023 at 08:59:05PM +0200, Linus Walleij wrote:
> On Tue, Oct 17, 2023 at 8:34 PM Andy Shevchenko
> <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> > On Tue, Oct 17, 2023 at 08:18:23PM +0200, Linus Walleij wrote:
> 
> > > In the past some file system developers have told us (Ulf will know)
> > > that we can't rely on the block device enumeration to identify
> > > devices, and requires that we use things such as sysfs or the
> > > UUID volume label in ext4 to identify storage.
> >
> > While I technically might agree with you, this was working for everybody
> > since day 1 of support of Intel Merrifield added (circa v4.8), now _user
> > space_ is broken.
> 
> Actually, I don't agree with that, just relaying it. I would prefer that we
> solve exactly the problem that we are facing here: some random unrelated
> code or similar affecting enumeration order of mmc devices.
> 
> It's not the first time it happens to me, I have several devices that change
> this enumeration order depending on whether an SD card is plugged
> in or not, and in a *BIG* way: the boot partition on the soldered eMMC
> changes enumeration depending on whether an SD card is inserted
> or not, and that has never been fixed (because above).

This is not the problem I have. I haven't added any SD card, hardware
configuration is the same. The solely difference in the whole setup is
this revert applied or not.

> > > That said, device trees are full of stuff like this:
> > >
> > >         aliases {
> > >                 serial0 = &uart_AO;
> > >                 mmc0 = &sd_card_slot;
> > >                 mmc1 = &sdhc;
> > >         };
> >
> > And Rob, AFAIU, is against aliases.
> >
> > > Notice how this enumeration gets defined by the aliases.
> > >
> > > Can you do the same with device properties? (If anyone can
> > > answer that question it's Dmitry!)
> >
> > No, and why should we?
> 
> Because device properties are not device tree, they are just some
> Linux thing so we can do whatever we want. Just checking if
> Dmitry has some idea that would solve this for good, he usually
> replies quickly.

OK.

-- 
With Best Regards,
Andy Shevchenko