if_delmpanic: uma: Freed item 0xfffff80045732000 did not belong to zone mbuf_cluster cpuid = 1 time = 1570169980 KDB: stack backtrace: db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame 0xfffffe0022b766b0 vpanic() at vpanic+0x1e0/frame 0xfffffe0022b76710 panic() at panic+0x43/frame 0xfffffe0022b76770 uma_dbg_free() at uma_dbg_free+0x26b/frame 0xfffffe0022b767c0 uma_zfree_arg() at uma_zfree_arg+0x1a2/frame 0xfffffe0022b76850 mb_free_ext() at mb_free_ext+0x24f/frame 0xfffffe0022b76890 freebsd32_sendmsg() at freebsd32_sendmsg+0x6b4/frame 0xfffffe0022b76970 ia32_syscall() at ia32_syscall+0x46a/frame 0xfffffe0022b76ab0 int0x80_syscall_common() at int0x80_syscall_common+0x9c/frame 0x8142fca KDB: enter: panic [ thread pid 1576 tid 100678 ] Stopped at kdb_enter+0x6a: movq $0,kdb_why