Hi,

We have been observing an issue that IO BARs can’t be claimed due to resource

conflict.

[ 0.457693] pci 0000:00:1d.0: can't claim BAR 4 [io 0x92a0-0x92bf]: address conflict with PCI Bus 0000:01 [io 0x9000-0x9fff]

[ 0.457705] pci 0000:00:1d.1: can't claim BAR 4 [io 0x9280-0x929f]: address conflict with PCI Bus 0000:01 [io 0x9000-0x9fff]

[ 0.457715] pci 0000:00:1d.2: can't claim BAR 4 [io 0x9260-0x927f]: address conflict with PCI Bus 0000:01 [io 0x9000-0x9fff]

[ 0.457743] pci 0000:00:1f.2: can't claim BAR 4 [io 0x9240-0x925f]: address conflict with PCI Bus 0000:01 [io 0x9000-0x9fff]

[ 0.457754] pci 0000:00:1f.3: can't claim BAR 4 [io 0x9200-0x923f]: address conflict with PCI Bus 0000:01 [io 0x9000-0x9fff]

Please see the discussion thread:

The root of the problem is that OVMF does not take into account the limit register’s granularity (limit) of a bridge,

and programs EPs with overlapping IO ranges in a different bus.

Should we fix the issue in the OVMF?

Thanks,

Kallol