Bug 227759

Something I've begun to witness on stable/11 r332847:

pcib0: <ACPI Host-PCI bridge> port 0xcf8-0xcff on acpi0
pcib0: _OSC failed: AE_BUFFER_OVERFLOW

Data points:

* System works/functions fine.

* This is a bare metal system: Supermicro X7SBA motherboard running latest BIOS.  (Yes, the system is "old-ish", but is very stable)

* pciconf -lvcb output does not list pcib0, so I cannot get further details of that device.

* I don't know when this problem began.  It may have been there for some time.  Machine previously ran stable/9 (I moved to stable/11 3-4 months ago; full OS reinstall).

* I believe _OSC comes from ACPI DSDT table, and that this particular attribute is *very* important depending on what device (UUID) it's referring to -- but I cannot figure out that UUID.  This message is therefore of concern, especially because it doesn't disclose what buffer/integer may have overflowed.  I am not worried about security, I am worried that there is a particular PCI-level feature or aspect that is incorrectly being handled.

I will attach several things:

* acpidump -dtv 2>&1 output
* acpidump -dt output
* pciconf -lvcb output (don't think this will help, see above)
* dmesg output

I am hoping someone has some idea what rXXXXXX commit may have introduced this.  I can roll the system back to a previous commit for testing, but I cannot simply roll back one commit at a time -- this would take literally weeks.  I do believe there were some recent ACPI changes, however.