uvm_fault(0xfffffd807ece6a10, 0x7f838806da10, 0, 2) -> e
kernel: page fault trap, code=2
Stopped at      pmap_page_remove+0x43d: xchgq   %rax,0(%r12,%rcx,1)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
pmap_page_remove(fffffd8007279a00) at pmap_page_remove+0x43d _atomic_swap_64 sys/arch/amd64/compile/SYZKALLER/obj/machine/atomic.h:117 [inline]
pmap_page_remove(fffffd8007279a00) at pmap_page_remove+0x43d sys/arch/amd64/amd64/pmap.c:2014
uvm_anfree(fffffd807c042de0) at uvm_anfree+0xd8 sys/uvm/uvm_anon.c:111
amap_wipeout(fffffd80700fef00) at amap_wipeout+0x246 sys/uvm/uvm_amap.c:-1
uvm_unmap_detach(ffff80002a7fede0,0) at uvm_unmap_detach+0x8a sys/uvm/uvm_map.c:1359
uvm_map_teardown(fffffd807ece6a10) at uvm_map_teardown+0x357 sys/uvm/uvm_map.c:2536
exit1(ffff80002a787768,0,9,1) at exit1+0x6e6 sys/kern/kern_exit.c:259
sigexit(ffff80002a787768,9) at sigexit+0x115
postsig(ffff80002a787768,9,ffff80002a7ff008) at postsig+0x686 sys/kern/kern_sig.c:1763
userret(ffff80002a787768) at userret+0x23e sys/kern/kern_sig.c:2207
syscall(ffff80002a7ff130) at syscall+0xa56 mi_syscall_return sys/sys/syscall_mi.h:203 [inline]
syscall(ffff80002a7ff130) at syscall+0xa56 sys/arch/amd64/amd64/trap.c:804
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7aeacbf97880, count: 4
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