panic: kernel diagnostic assertion "uvm_page_owner_locked_p(pg)" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_page.c", line 1269
Stopped at      db_enter+0x18:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 171737  36756      0         0x2  0x4000001    1  syz-fuzzer
*225740  20544      0     0x14000      0x200    0K reaper
db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff827511ac) at panic+0x177 sys/kern/subr_prf.c:198
__assert(ffffffff827ccb0f,ffffffff8273af68,4f5,ffffffff8277486d) at __assert+0x25 sys/kern/subr_prf.c:157
uvm_pageunwire(fffffd8006d09260) at uvm_pageunwire+0x16b sys/uvm/uvm_page.c:1269
uvm_fault_unwire_locked(fffffd80089b2450,b0b8c2c3000,b0b8c4c2000) at uvm_fault_unwire_locked+0x236 sys/uvm/uvm_fault.c:1683
uvm_unmap_kill_entry_withlock(fffffd80089b2450,fffffd806bde0218,0) at uvm_unmap_kill_entry_withlock+0x67 sys/uvm/uvm_map.c:1925
uvm_map_teardown(fffffd80089b2450) at uvm_map_teardown+0x187 uvm_map_addr_RBT_LEFT sys/uvm/uvm_map.h:176 [inline]
uvm_map_teardown(fffffd80089b2450) at uvm_map_teardown+0x187 sys/uvm/uvm_map.c:2578
uvmspace_free(fffffd80089b2450) at uvmspace_free+0xa6 sys/uvm/uvm_map.c:3513
reaper(ffff8000211bd5c8) at reaper+0x19a sys/kern/kern_exit.c:448
end trace frame: 0x0, count: 6
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