syzbot

uvm_fault(fffffd80709886e8,618cd00e000,0,1) at uvm_fault+0x169 sys/uvm/uvm_fault.c:605
upageflttrap(ffff80002c7f72a0,618cd00eff8) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188
usertrap(ffff80002c7f72a0) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436
recall_trap() at recall_trap+0x8
end of kernel
end trace frame: 0x7902c9b44aa0, count: -13
ddb{0}> machine ddbcpu 1
Stopped at      dopselect+0xc94:        int     $3
ddb{1}> trace
end trace frame: 0x0, count: -1