Bug 217352

Summary: AER Unsupported Request errors for LTR Messages from iwlwifi
Product: Drivers Reporter: Bjorn Helgaas (bjorn)
Component: PCIAssignee: drivers_pci (drivers_pci)
Status: NEW ---    
Severity: normal    
Priority: P3    
Hardware: All   
OS: Linux   
Kernel Version: Subsystem:
Regression: No Bisected commit-id:
Attachments: dmesg with pci=earlydump

Description Bjorn Helgaas 2023-04-18 19:24:19 UTC 
Created attachment 304158 [details]
dmesg with pci=earlydump

Ben Greear reported new Unsupported Request errors [1] after 8795e182b02d ("PCI/portdrv: Don't disable AER reporting in get_port_device_capability()"), which caused AER reporting to be enabled in more cases.

I think the problem is that an iwlwifi device has LTR enabled, so it sends LTR messages upstream periodically.  But one of the ports upstream from it has LTR *disabled*, so it reports an Unsupported Request.

Attaching dmesg log with "pci=earlydump" so we can see whether BIOS left LTR in this state or Linux broke something.

[1] https://lore.kernel.org/r/47b775c5-57fa-5edf-b59e-8a9041ffbee7@candelatech.com