panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_page.c", line 144
Stopped at      db_enter+0x1c:  addq    $0x8,%rsp
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*357034  47517      0   0x8000002          0    1  syz-executor.3
 417384  31082      0     0x14000 0x40000200    0K softclock
db_enter() at db_enter+0x1c sys/arch/amd64/amd64/db_interface.c:437
panic(ffffffff82950700) at panic+0x17b sys/kern/subr_prf.c:198
__assert(ffffffff8290a0dd,ffffffff828ae757,90,ffffffff8290e1bd) at __assert+0x29 sys/kern/subr_prf.c:157
uvm_pagealloc_pg(fffffd80075a3ba0,fffffd806a97ccf8,1dfa8000,0) at uvm_pagealloc_pg+0x3e9 sys/uvm/uvm_page.c:695
uvm_pagealloc(fffffd806a97ccf8,1dfa8000,0,3) at uvm_pagealloc+0x1ed sys/uvm/uvm_page.c:917
pmap_get_ptp(fffffd806a97cca8,77ea27833000) at pmap_get_ptp+0x18d sys/arch/amd64/amd64/pmap.c:1215
pmap_enter(fffffd806a97cca8,77ea27833000,6b421000,1,20) at pmap_enter+0x2c6 sys/arch/amd64/amd64/pmap.c:2722
uvm_fault_upper_lookup(ffff800033f4f530,ffff800033f4f568,ffff800033f4f430,ffff800033f4f4b0) at uvm_fault_upper_lookup+0x2b2
uvm_fault(fffffd806903e8a0,77ea27834000,0,1) at uvm_fault+0x129 sys/uvm/uvm_fault.c:605
upageflttrap(ffff800033f4f6b0,77ea27834630) at upageflttrap+0x8b sys/arch/amd64/amd64/trap.c:188
usertrap(ffff800033f4f6b0) at usertrap+0x227 sys/arch/amd64/amd64/trap.c:436
recall_trap() at recall_trap+0x8
end of kernel
end trace frame: 0x77ea27834650, count: 3
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