zfs recv panic

Hi,

I have a reproducible panic on CURRENT (r318136) doing
(jupiter) # zfs send -R -v zroot/var_at_before-kernel-2017-04-26 | nc dual 
1234
(dual) # nc -l 1234 | zfs recv -v -F tank/jupiter/var

For clarity, the receiving machine is CURRENT r318136, the sending 
machine is running a somewhat older CURRENT version.

The receiving machine panics a few seconds in:

receiving full stream of zroot/var_at_before-kernel-2017-04-03 into 
tank/jupiter/var_at_before-kernel-2017-04-03
panic: solaris assert: dbuf_is_metadata(db) == arc_is_metadata(buf) (0x0 
== 0x1), file: 
/usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c, line: 
2007
cpuid = 0
time = 1494408122
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x2b/frame 
0xfffffe0120cad930
vpanic() at vpanic+0x19c/frame 0xfffffe0120cad9b0
panic() at panic+0x43/frame 0xfffffe0120cada10
assfail3() at assfail3+0x2c/frame 0xfffffe0120cada30
dbuf_assign_arcbuf() at dbuf_assign_arcbuf+0xf2/frame 0xfffffe0120cada80
dmu_assign_arcbuf() at dmu_assign_arcbuf+0x170/frame 0xfffffe0120cadad0
receive_writer_thread() at receive_writer_thread+0x6ac/frame 
0xfffffe0120cadb70
fork_exit() at fork_exit+0x84/frame 0xfffffe0120cadbb0
fork_trampoline() at fork_trampoline+0xe/frame 0xfffffe0120cadbb0
--- trap 0, rip = 0, rsp = 0, rbp = 0 ---
KDB: enter: panic
[ thread pid 7 tid 100672 ]
Stopped at      kdb_enter+0x3b: movq    $0,kdb_why
db>


kgdb backtrace:
#0  doadump (textdump=0) at pcpu.h:232
#1  0xffffffff803a208b in db_dump (dummy=<value optimized out>, 
dummy2=<value optimized out>, dummy3=<value optimized out>, 
dummy4=<value optimized out>) at /usr/src/sys/ddb/db_command.c:546
#2  0xffffffff803a1e7f in db_command (cmd_table=<value optimized out>) 
at /usr/src/sys/ddb/db_command.c:453
#3  0xffffffff803a1bb4 in db_command_loop () at 
/usr/src/sys/ddb/db_command.c:506
#4  0xffffffff803a4c7f in db_trap (type=<value optimized out>, 
code=<value optimized out>) at /usr/src/sys/ddb/db_main.c:248
#5  0xffffffff80a93cb3 in kdb_trap (type=3, code=-61456, tf=<value 
optimized out>) at /usr/src/sys/kern/subr_kdb.c:654
#6  0xffffffff80ed3de6 in trap (frame=0xfffffe0120cad860) at 
/usr/src/sys/amd64/amd64/trap.c:537
#7  0xffffffff80eb62f1 in calltrap () at 
/usr/src/sys/amd64/amd64/exception.S:236
#8  0xffffffff80a933eb in kdb_enter (why=0xffffffff8143d8f5 "panic", 
msg=<value optimized out>) at cpufunc.h:63
#9  0xffffffff80a51cf9 in vpanic (fmt=<value optimized out>, 
ap=0xfffffe0120cad9f0) at /usr/src/sys/kern/kern_shutdown.c:772
#10 0xffffffff80a51d63 in panic (fmt=<value optimized out>) at 
/usr/src/sys/kern/kern_shutdown.c:710
#11 0xffffffff8262b26c in assfail3 (a=<value optimized out>, lv=<value 
optimized out>, op=<value optimized out>, rv=<value optimized out>, 
f=<value optimized out>, l=<value optimized out>)
     at 
/usr/src/sys/cddl/compat/opensolaris/kern/opensolaris_cmn_err.c:91
#12 0xffffffff822ad892 in dbuf_assign_arcbuf (db=0xfffff8008f23e560, 
buf=0xfffff8008f09fcc0, tx=0xfffff8008a8d5200) at 
/usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dbuf.c:2007
#13 0xffffffff822b87f0 in dmu_assign_arcbuf (handle=<value optimized 
out>, offset=0, buf=0xfffff8008f09fcc0, tx=0xfffff8008a8d5200) at 
/usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu.c:1542
#14 0xffffffff822bf7fc in receive_writer_thread (arg=0xfffffe0120a1d168) 
at 
/usr/src/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/dmu_send.c:2284
#15 0xffffffff80a13704 in fork_exit (callout=0xffffffff822bf150 
<receive_writer_thread>, arg=0xfffffe0120a1d168, 
frame=0xfffffe0120cadbc0) at /usr/src/sys/kern/kern_fork.c:1038
#16 0xffffffff80eb682e in fork_trampoline () at 
/usr/src/sys/amd64/amd64/exception.S:611
#17 0x0000000000000000 in ?? ()

Let me know if there’s any other information I can provide, or things 
I can test.
Fortunately the target machine is not a production machine, so I can 
panic it as often as required.

Regards,
Kristof