- fallback.rs: config reads at offset >= 256 (PCIe extended space) now
return the PCI-standard 0xFFFFFFFF 'absent' value and writes are
dropped, instead of panicking the PCI daemon. This is the exact
behavior of real hardware and Linux's CF8 path on MCFG-less machines,
and it lets MSI-X feature discovery degrade to INTx cleanly. Found by
the first driver-manager QEMU gate (i440fx): pcid panicked at
fallback.rs:65 and the boot hung.
- driver_handler.rs: drop vestigial func param from read_full_device_id.
- driver_interface/mod.rs: use Option::insert's return value directly
(must_use) instead of discarding and re-reading as_ref.
Red Bear OS