Re: [PATCH] PCI: Always lift 2.5GT/s restriction in PCIe failed link retraining

[Maciej W. Rozycki]

On Thu, 19 Feb 2026, Bjorn Helgaas wrote:

> > Can we reconsider my patch that restricts the link retrain mechanism
> > to the specific device that created the work-around?
> > https://lore.kernel.org/all/20250702052430.13716-1-mattc@xxxxxxxxxxxxxxx/
> 
> I think we already at least potentially meddle with the link on every
> device, and it definitely makes me nervous.  I would like it much
> better if it's possible to limit it to devices with known defects.
> 
> I'll defer these for now and we can see if a consensus emerges.

 As I say it's logically impossible to figure out whether or not to apply 
such a workaround where the culprit is the downstream device, because 
until you've succeeded establishing a link you have no way to figure out 
what the downstream device actually is.

  Maciej