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Re: Udev-based serial number dependent symlinks for PCIe UIO devices

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On 5/18/2021 2:17 PM, Wojciech Zabolotny wrote:
> I'm working at a system, where a server manages multiple PCIe data
> acquisition cards. Each card has its individual serial number available in
> the extended PCIe configuration space. The cards are controlled as UIO
> devices. Unfortunately, it appears that the card are sometimes enumerated in
> the random order. Proper management of the system requires that there are
> symlinks created with names permanently associated with the individual
> cards.

[I don't run Linux, so...]

Can't you adjust the kernel configuration so that it forces
certain probes to yield certain "devices"?

E.g., instead of letting NetBSD probe disk drives in whatever order
it encounters them -- and assigning device names in that order -- I
build my kernels so certain device names are set aside for specific
devices (which may or may not be present at any given boot).

So, the first "free" probed device might be /dev/xx4 instead of
/dev/xx0 -- because I want to ensure /dev/xx0 is available for
a *specific* device instead of letting it go to the "first one
found".

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Udev-based  serial number dependent symlinks for PCIe UIO devices Wojciech Zabolotny <wzab01@gmail.com> - 2021-05-18 14:17 -0700
  Re: Udev-based serial number dependent symlinks for PCIe UIO devices Don Y <blockedofcourse@foo.invalid> - 2021-05-18 21:13 -0700
    Re: Udev-based serial number dependent symlinks for PCIe UIO devices Theo <theom+news@chiark.greenend.org.uk> - 2021-05-19 09:30 +0100
      Re: Udev-based serial number dependent symlinks for PCIe UIO devices Don Y <blockedofcourse@foo.invalid> - 2021-05-19 01:51 -0700
        Re: Udev-based serial number dependent symlinks for PCIe UIO devices Wojciech Zabolotny <wzab01@gmail.com> - 2021-05-19 02:59 -0700

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