panic: sndbuf_getbufofs: ofs invalid 268435456
cpuid = 0
Trace beginning at frame 0xfffff801182494e8
sndbuf_getbufofs() at sndbuf_getbufofs+0x2b 0xffffffff826ff3eb 
sndbuf_getbufofs() at sndbuf_getbufofs+0x2b 0xffffffff826ff3eb 
dsp_mmap_single() at dsp_mmap_single+0x149 0xffffffff82707649 
dev_dmmap_single() at dev_dmmap_single+0x5e 0xffffffff8062cf2e 
vm_mmap() at vm_mmap+0x6d8 0xffffffff809a9e88 
kern_mmap() at kern_mmap+0x378 0xffffffff809aa2a8 
Debugger("panic")

CPU0 stopping CPUs: 0x0000003e
 stopped
Stopped at      Debugger+0x7c:  movb    $0,0xbdaf09(%rip)
db>