uvm_fault(0xffffffff82c310b0, 0xffff800016edf000, 0, 2) -> d
kernel: page fault trap, code=0
Stopped at      memset+0x4e:    repe stosq      %es:(%rdi)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
* 75464  19869      0           0  0x4000000    0  syz-executor.5
memset() at memset+0x4e
VOP_WRITE(fffffd806b888b08,ffff80002b411b40,0,fffffd807f7d77b8) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245
uvn_io(fffffd806e2ed290,ffff80002b411d30,6,31,1) at uvn_io+0x369 sys/uvm/uvm_vnode.c:1269
uvn_put(fffffd806e2ed290,ffff80002b411d30,6,31) at uvn_put+0xd0 sys/uvm/uvm_vnode.c:926
uvm_pager_put(fffffd806e2ed290,fffffd800616b480,ffff80002b411dc8,ffff80002b411e08,31,0,53fe034f984b7f5) at uvm_pager_put+0x137 sys/uvm/uvm_pager.c:545
uvn_flush(fffffd806e2ed290,0,0,31) at uvn_flush+0x52e sys/uvm/uvm_vnode.c:725
uvm_vnp_sync(ffff8000006da000) at uvm_vnp_sync+0x15f sys/uvm/uvm_vnode.c:1540
sys_sync(ffff8000216dc028,ffff80002b411f18,ffff80002b411f60) at sys_sync+0x9b sys/kern/vfs_syscalls.c:536
syscall(ffff80002b411fe0) at syscall+0x484 sys/arch/amd64/amd64/trap.c:606
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xf918f1aeb50, count: 5
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