Boot panic w/7.2-STABLE on amd64: resource_list_alloc

[Bruce Simpson]

Hi,

Since upgrading sources on RELENG_7 yesterday, my amd64 system panics 
right after this line in dmesg:

ata4: <ATA channel 2> on atapci1
panic: resource_list_alloc: resource entry is busy

This machine uses an ALi SATA controller. I haven't had any problems 
with this controller's support for most of the 7.x branch, but it was 
last broken during the 6.x branch.

I see there have recently been commits in this area which may have 
broken ATA driver support in some subtle way.

Backtrace is (w/o symbols):-
...
resource_list_alloc()
pci_alloc_resource()
bus_alloc_resource()
ata_ali_sata_allocate()
ata_pcichannel_attach()
device_attach()
...

There are no debugging symbols at the moment as this is a production kernel.
If any further information is required to resolve the bug, please let me 
know.

thanks,
BMS