I just tried an i386 kernel compiled with May 18 14:01 GMT source on a vaio
with a single pcmcia slot. I popped in a modem card and the whole thing froze -
no beeps, no response to ping. Removing the card didn't make it spring back to
life.

A bit from dmesg:

cbb0 at pci0 dev 12 function 0: Ricoh 5C475 PCI-CardBus bridge (CardBus bridge, revision 0x80) at ? dev 12 function 0 (tag 0x80006000, intrtag 0x80006000, intrswiz 0, intrpin 0x1, i/o on, mem on, no quirks): Ricoh 5C475 PCI-CardBus bridge (rev. 0x80)

fxp0: interrupting at irq 9
cbb0: interrupting at irq 9
cardslot0 at cbb0 slot 0 flags 0
cardbus0 at cardslot0: bus 2 device 0 cacheline 0x0, lattimer 0x20
pcmcia0 at cardslot0

options         PCIBIOS                 # PCI BIOS support 
options         PCIBIOSVERBOSE          # PCI BIOS verbose info
options         PCIBIOS_ADDR_FIXUP      # fixup PCI I/O addresses
options         PCIBIOS_BUS_FIXUP       # fixup PCI bus numbering  
options         PCIBIOS_INTR_FIXUP      # fixup PCI interrupt routing
options         PCIINTR_DEBUG           # super-verbose PCI interrupt fixup

I vaguely remember that the shared irqs are OK.. any thoughts about the
cardbus support?

Cheers,

Patrick