Fatal trap 12 after ata probe

I"m trying to upgrade to current on a Sony Z1.  5.2.1-RELEASE boots OK,
but when I try to boot with current I cvsupped today I get:

Memory modified after free 0xc457da00(508) val=1ff01ff _at_ 0xc457da00

Fatal trap 12: page fault while in kernel mode
Stopped at  mtrash_ctor+0x31

right after it probes ata.  Here's the stack trace:

mtrash_ctor(c457da00,200,0) at mtrash_ctor+0x3a
uma_zalloc_arg(c1038e00,0,1) at uma_zalloc_arg+0x169
malloc(200,c07fd680,1,c,a165f000) at malloc+0xb7
ata_getparam(c4468ca8,a1) at ata_getparam+0x30
ata_identify_devices(c4468c00) at ata_identify_devices+0x10a
ata_boot_attach(0) at ata_boot_attach+0x27
run_interrupt_driven_config_hooks(0,c1ec00,c1e000,0,c043d9d5) at
run_interrupt_driven_config_hooks+0x18
mi_startup() at mi_startup+0x96
begin() at begin+0x2c

I tried to get it to dump but it gets another trap when I type "panic".

Any ideas?

Thanks,

-- Bob