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That's right. The symptoms can vary, i.e. sometimes it retrains with lower lane count, and sometimes config reads start timing out, and very often it works just fine. > I see you're from NVIDIA, so if you're confirming that this is a > hardware erratum (not an issue with the GB10 PCI controller driver), > we should definitely apply this, and I'll wordsmith the commit log > and comment something like this: > > When asserting Secondary Bus Reset to downstream devices via a GB10 > Root Port, the link doesn't retrain correctly. The link may retrain > with a lower lane count, and config accesses to downstream devices > may fail. Yes, I confirm this is a HW erratum. The problem doesn't occur every time, so "the link may not retrain correctly" would be more correct, but that's a minor comment. Terje