sys/net/if_clone_test:epair_up_stress  ->  Kernel page fault with the following non-sleepable locks held:
exclusive sleep mutex if_addr_lock (if_addr_lock) r = 0 (0xc000000029ad81a8) locked @ /usr/src/sys/net/if.c:3686
stack backtrace:
#0 0xc0080000004b1514 at witness_debugger+0xa4
#1 0xc0080000004b29ec at witness_warn+0x49c
#2 0xc008000000767a18 at trap_pfault+0x2a8
#3 0xc0080000007669c8 at trap+0x248
#4 0xc00800000075b6f0 at powerpc_interrupt+0x1a0

fatal kernel trap:

   exception       = 0x300 (data storage interrupt)
   virtual address = 0xdeadc0dedeadc0de
   esr             = 0x0
   srr0            = 0xc0080000005ae2dc (0x5ae2dc)
   srr1            = 0x80029000
   current msr     = 0x80029000
   lr              = 0xc0080000005ae2ac (0x5ae2ac)
   frame           = 0xc008000022be70a0
   curthread       = 0xc008000022c53b00
          pid = 0, comm = thread taskq

panic: data storage interrupt trap
cpuid = 1
time = 1592544415
KDB: stack backtrace:
0xc008000022be6c00: at kdb_backtrace+0x60
0xc008000022be6d10: at vpanic+0x1e4
0xc008000022be6dc0: at panic+0x44
0xc008000022be6df0: at trap_pfault+0x338
0xc008000022be6eb0: at trap+0x248
0xc008000022be6fe0: at powerpc_interrupt+0x1a0
0xc008000022be7070: kernel DSI read trap @ 0xdeadc0dedeadc0de by rtsock_msg_mbuf+0x16c: srr1=0x80029000
            r1=0xc008000022be7320 cr=0x42840c40 xer=0 ctr=0 r2=0xc008000000bbb000 sr=0 frame=0xc008000022be70a0
0xc008000022be7320: at rtsock_msg_mbuf+0x138
0xc008000022be7440: at rt_newmaddrmsg+0xb4
0xc008000022be7540: at if_delmulti_locked+0x90
0xc008000022be75c0: at if_delmulti_ifma_flags+0x94
0xc008000022be7610: at inm_release_task+0x348
0xc008000022be76d0: at taskqueue_run_locked+0x100
0xc008000022be77d0: at taskqueue_thread_loop+0xcc
0xc008000022be7820: at fork_exit+0xc4
0xc008000022be78c0: at fork_trampoline+0x18
0xc008000022be78f0: at -0x4
KDB: enter: panic
[ thread pid 0 tid 100014 ]
Stopped at      kdb_enter+0x78: ori     r0, r0, 0x0
db>