uvm_fault(0xfffffd8067f5fc20, 0x7f8000100000, 0, 2) -> e
kernel: page fault trap, code=2
Stopped at      pmap_page_remove+0x33d: xchgq   %rax,0(%r14,%rcx,1)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
 255184  96473      0   0x8000000          0    0  syz-executor.2
*393310  96473      0   0x8000000  0x4000000    1  syz-executor.2
pmap_page_remove(fffffd8007480d80) at pmap_page_remove+0x33d _atomic_swap_64 machine/atomic.h:117 [inline]
pmap_page_remove(fffffd8007480d80) at pmap_page_remove+0x33d sys/arch/amd64/amd64/pmap.c:1990
uvm_anfree_list(fffffd80690958d0,0) at uvm_anfree_list+0x98
amap_wiperange_chunk(fffffd8061555228,fffffd8061555258,0,1) at amap_wiperange_chunk+0x15f sys/uvm/uvm_amap.c:983
amap_pp_adjref(fffffd8061555228,0,2,ffffffff) at amap_pp_adjref+0x54b sys/uvm/uvm_amap.c:944
amap_adjref_anons(fffffd8061555228,0,2,ffffffff,0) at amap_adjref_anons+0x182 sys/uvm/uvm_amap.c:1329
uvm_unmap_detach(ffff80002a2825e8,0) at uvm_unmap_detach+0x7d sys/uvm/uvm_map.c:1354
uvm_mapanon(fffffd8067f5fc20,ffff80002a282800,2000,0,1090710) at uvm_mapanon+0x64f sys/uvm/uvm_map.c:910
uvm_mmapanon(fffffd8067f5fc20,ffff80002a282800,2000,0,7,1012,bfe73cd89f34619e,1012) at uvm_mmapanon+0x17f sys/uvm/uvm_mmap.c:1020
sys_mmap(ffff80002bcb47f0,ffff80002a282970,ffff80002a2828c0) at sys_mmap+0x7b2 sys/uvm/uvm_mmap.c:421
syscall(ffff80002a282970) at syscall+0x8cf mi_syscall sys/sys/syscall_mi.h:180 [inline]
syscall(ffff80002a282970) at syscall+0x8cf sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xcf8ea1f6050, count: 4
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