panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/main/kernel/sys/uvm/uvm_page.c", line 144
Stopped at      db_enter+0x1c:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*206448  11963      0           0          0    0  syz-executor.1
db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff8292bec0) at panic+0x165 sys/kern/subr_prf.c:198
__assert(ffffffff828dfc90,ffffffff8282d138,90,ffffffff828e1afc) at __assert+0x29 sys/kern/subr_prf.c:157
uvm_pagealloc_pg(fffffd8006435900,fffffd806f344bf8,3a272a000,0) at uvm_pagealloc_pg+0x3e9 sys/uvm/uvm_page.c:695
uvm_pagealloc(fffffd806f344bf8,3a272a000,0,3) at uvm_pagealloc+0x1ed sys/uvm/uvm_page.c:917
pmap_get_ptp(fffffd806f344be8,744e5582000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1215
pmap_enter(fffffd806f344be8,744e5582000,6957e000,4,20) at pmap_enter+0x2b0
uvm_fault_lower_lookup(ffff800031965320,ffff800031965358,ffff8000319652a0) at uvm_fault_lower_lookup+0x25a sys/uvm/uvm_fault.c:1192
uvm_fault_lower(ffff800031965320,ffff800031965358,ffff8000319652a0,0) at uvm_fault_lower+0x63 sys/uvm/uvm_fault.c:1227
uvm_fault(fffffd807b73d860,744e5585000,0,4) at uvm_fault+0x22a sys/uvm/uvm_fault.c:637
upageflttrap(ffff8000319654a0,744e5585f5b) at upageflttrap+0x85 sys/arch/amd64/amd64/trap.c:188
usertrap(ffff8000319654a0) at usertrap+0x20e sys/arch/amd64/amd64/trap.c:436
recall_trap() at recall_trap+0x8
end of kernel
end trace frame: 0x77607e6a5c00, count: 2
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