panic: vm_page_assert_xbusied: page 0xd0000000c6bfc938 not exclusive busy @ /usr/local-src/sys/vm/vm_page.c:1555
cpuid = 143
time = 1580547888
KDB: stack backtrace:
0xe0000000c14f1160: at kdb_backtrace+0x60
0xe0000000c14f1270: at vpanic+0x1e4
0xe0000000c14f1320: at panic+0x40
0xe0000000c14f1350: at vm_page_remove_xbusy+0x244
0xe0000000c14f13d0: at vm_page_assert_pga_writeable+0x964
0xe0000000c14f1450: at vm_page_free+0x58
0xe0000000c14f14e0: at sysctl_handle_uma_zone_cur+0x26f8
0xe0000000c14f1570: at sysctl_handle_uma_zone_cur+0x3e04
0xe0000000c14f15f0: at sysctl_handle_uma_zone_cur+0x32d4
0xe0000000c14f16b0: at uma_reclaim+0x1a0
0xe0000000c14f1750: at uma_reclaim_worker+0xbc
0xe0000000c14f1820: at fork_exit+0xc4
0xe0000000c14f18c0: at fork_trampoline+0x18
0xe0000000c14f18f0: at -0x4
KDB: enter: panic
[ thread pid 162 tid 101134 ]
Stopped at      kdb_enter+0x78: ori     r0, r0, 0x0
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