PCI error message during boot (mostly harmless)

I’ve seen this a few times during what should be a ‘quiet’ boot (meaning I shouldn’t be seeing info messages between boot and graphical UI):

PCI 0000:00:07.0 RP PIO log size 0 is invalid
PCI 0000:00:07.1 RP PIO log size 0 is invalid
PCI 0000:00:07.2 RP PIO log size 0 is invalid
PCI 0000:00:07.3 RP PIO log size 0 is invalid

PCI 07 corresponds to the following (via lspci):

00:07.0 PCI bridge: Intel Corporation Tiger Lake-LP Thunderbolt 4 PCI Express Root Port #0 (rev 01)
00:07.1 PCI bridge: Intel Corporation Tiger Lake-LP Thunderbolt 4 PCI Express Root Port #1 (rev 01)
00:07.2 PCI bridge: Intel Corporation Tiger Lake-LP Thunderbolt 4 PCI Express Root Port #2 (rev 01)
00:07.3 PCI bridge: Intel Corporation Tiger Lake-LP Thunderbolt 4 PCI Express Root Port #3 (rev 01)

Googling around, it appears this message is due to a hardware misconfiguration:

It sure looks like the device is out of spec because PCIe r5.0, sec 7.9.15.2, says: “RP PIO Log Size - This field indicates how many DWORDs are allocated for the RP PIO log registers, comprised by the RP PIO Header Log, the RP PIO ImpSpec Log, and RP PIO TLP Prefix Log. If the Root Port supports RP Extensions for DPC, the value of this field must be 4 or greater; otherwise, the value of this field must be 0.” (source)

As far as I can tell, there is no negative side effect (unless this has something to do with laptop not being able to wake from sleep… just speculating). I thought I’d write it down though since it’s a hard message to “catch”.

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Had the same error message. I initially try to boot an iso by usb-a but coulnd not get this to work because of usb device descriptor read error that would pop up right after those errors. I then tried to boot an iso using usb-c and for reasons that elude me booting only had the first set of error and now everything work ok.