On Sat, Jan 24, 2026 at 03:32:17PM -0800, Ethan Nelson-Moore wrote:

On Fri, Jan 23, 2026 at 11:25 PM Christophe Leroy (CS GROUP)
[off-list ref] wrote:

quoted

Yes and that's exactly the reason why removing unused IDs will be a problem.

Let's take an exemple: some patch adds PCI_DEVICE_ID_ARECA_1682 after
PCI_DEVICE_ID_ARECA_1681 in pci_ids.h in the mainline. That patch needs
to be backported and it conflicts with PCI_VENDOR_ID_S2IO which is not
anymore in the mainline but is still in stable.

Hi, Christophe,

I understand your reasoning now. Thanks for clarifying. In my opinion,
changes to pci_ids.h don't happen often enough for that to be a
problem. Unused IDs have been removed from it before.

What is the value in removing the IDs?

The values can never be reused for new hardware, so removal doesn't
make room for anything in the future.  Unlike the removal of driver
code, removing the IDs doesn't reduce complexity or improve
readability or maintainability.