PANIC: blockable slep lock (sx) msi _at_ ....msi.c:374

Hello,

recent changes (during the last 2 days,I guess tha acpi stuff) broke 
-current for me:

ad6: 476940MB <WDC WD5000KS-07MNB0 07.02E07> at ata3-master SATA300
SMP: AP CPU #1 Launched!
panic: blockable sleep lock (sx) msi _at_ /FlashBSD/src/sys/i386/i386/msi.c:374
cpuid = 0
KDB: enter: panic
[thread pid 0 tid 0 ]
Stopped at      kdb_enter+0x30: leave
db> bt
Tracing pid 0 tid 0 td 0xc07c2d60
kdb_enter(c07422df,0,c0746e47,c1420bdc,c07c2d60,...) at kdb_enter+0x30
panic(c0746e47,c073180d,c0732bb2,c0764c8e,176,...) at panic+0x135
witness_checkorder(c082f0fc,1,c0764c8e,176,c55c0980,...) at 
witness_checkorder+0xd6
_sx_slock(c082f0fc,c0764c8e,176,c1420c64,c06f7e65,...) at _sx_slock+0x5f
msi_map(100,c1420d08,c1420d04,c1420c94,c04b5cc5,...) at msi_map+0x22
nexus_map_msi(c5552000,c55e4000,100,c1420d08,c1420d04,...) at 
nexus_map_msi+0x1f
pcib_map_msi(c55d9080,c55e4000,100,c1420d08,c1420d04,...) at 
pcib_map_msi+0x86
pcib_map_msi(c55e4200,c55e4000,100,c1420d08,c1420d04,...) at 
pcib_map_msi+0x86
pci_remap_msi_irq(c55e4000,100,c06ecb73,c54fff78,100,...) at 
pci_remap_msi_irq+0xeb
msi_assign_cpu(c55e6240,0,100,c079d170,c1420d70,...) at msi_assign_cpu+0x68
intr_assign_next_cpu(c55e6240,0,c07631d3,1c7,c54f3a44,...) at 
intr_assign_next_cpu+0x23
intr_shuffle_irqs(0,141e000,141ec00,141e000,0,...) at intr_shuffle_irqs+0x5e
mi_startup() at mi_startup+0xa0
begin() at begin+0x2c
db>

Best regards,

-Harry