This happened during a bulk transfer from my i386 laptop to my
AlphaStation 200, with -current userland and kernel as of yesterday's sup.

fatal kernel trap:
panic: pool_get(mbpl): free list modified: magic=0; page 0xfffffc00029ca000; item addr 0xfffffc00029caa10

Stopped in ssh1 at      cpu_Debugger+0x4:       ret     zero,(ra)
db> t/t
cpu_Debugger() at cpu_Debugger+0x4
panic() at panic+0xec
_pool_get() at _pool_get+0x89c
tlp_rxintr() at tlp_rxintr+0x2bc
tlp_intr() at tlp_intr+0x8c
alpha_shared_intr_dispatch() at alpha_shared_intr_dispatch+0x3c
sio_iointr() at sio_iointr+0x80
interrupt() at interrupt+0x168
XentInt() at XentInt+0x1c
--- interrupt (from ipl 0) ---
esigcode() at esigcode+0x3c
XentInt() at XentInt+0x1c
--- interrupt ---
alpha_pal_swpipl() at alpha_pal_swpipl+0x4
spl0() at spl0+0x40
printf() at printf+0xd4
trap() at trap+0x574
XentUna() at XentUna+0x20
--- unaligned access fault ---
sbdrop() at sbdrop+0x98
tcp_input() at tcp_input+0x1ecc
ip_input() at ip_input+0x970
ipintr() at ipintr+0xb4
do_sir() at do_sir+0xe0
esigcode() at esigcode+0x2c
--- root of call graph ---

db> ps /w
 PID          COMMAND     EMUL  PRI UTIME STIME WAIT-MSG    WAIT-CHANNEL
>933             ssh1   netbsd   73   7.5   2.3
 932             scp1   netbsd   24   0.0   1.4 netio       0xfffffc00037808a0
 914               rc   netbsd   25   0.0   0.1 ttyin       0xfffffc0001288570
 913            xterm   netbsd   24   0.3   0.3 select      selwait
 910               rc   netbsd   32   0.0   0.0 wait        0xfffffc0004783d18
 908            sshd1   netbsd   24   2.1   0.9 select      selwait
 888               rc   netbsd   32   0.0   0.0 wait        0xfffffc00047821f8
 380               rc   netbsd   25   0.1   0.5 ttyin       0xfffffc0001288418
 379            xterm   netbsd   24   2.4   2.4 select      selwait
 376               rc   netbsd   32   0.0   0.0 wait        0xfffffc0004783938
 374            sshd1   netbsd   24   4.0   3.1 select      selwait
 285               rc   netbsd   25   0.1   0.6 ttyin       0xfffffc00012882c0
 284            xterm   netbsd   24   8.4  12.2 select      selwait
 281               rc   netbsd   32   0.0   0.0 wait        0xfffffc00047829b8
 279            sshd1   netbsd   24   8.9   8.9 select      selwait
 242               rc   netbsd   32   0.0   0.2 wait        0xfffffc0004782008
 241            xterm   netbsd   24   2.5   3.3 select      selwait
 238               rc   netbsd   32   0.0   0.0 wait        0xfffffc00012bc5d0
 236            sshd1   netbsd   24   3.9   3.1 select      selwait
 235       rc5des-netbsd-al   netbsd  1052476.6  35.2
 223            getty   netbsd   25   0.0   0.0 ttyin       0xfffffc0001288010
 209            sshd1   netbsd   24   2.4   0.0 select      selwait
 202            inetd   netbsd   24   0.0   0.0 select      selwait
 199            xntpd   netbsd   40   0.9   0.8 pause       0xfffffc00039788d8
 197             cron   netbsd   32   0.0   0.0 nanosleep   nanowait.136
 195           update   netbsd   40   0.0   1.7 pause       0xfffffc00012c3a70
 160        mount_mfs   netbsd   32   0.0   0.0 mfsidl      0xfffffc0003389c68
 153          portmap   netbsd   24   0.0   0.0 select      selwait
 147            named   netbsd   24   0.2   0.1 select      selwait
 143          syslogd   netbsd   24   0.4   1.7
 3             reaper   netbsd    4   0.0   0.0 reaper      deadproc
 2         pagedaemon   netbsd    4   0.0   0.0 daemon_slp  uvm+0x50
 1               init   netbsd   32   0.0   0.0 wait        0xfffffc00012bc000
 0            swapper   netbsd    4   0.0   0.0 scheduler   proc0