uvm_fault(0xffffffff82a5c398, 0xffff8000128bf000, 0, 2) -> d
kernel: page fault trap, code=0
Stopped at      memset+0x4e:    repe stosq      %es:(%rdi)
    TID    PID    UID     PRFLAGS     PFLAGS  CPU  COMMAND
*428705  31480      0           0  0x4000000    0  syz-executor.3
memset() at memset+0x4e
ffs_write(ffff80002e6d7900) at ffs_write+0x411 sys/ufs/ffs/ffs_vnops.c:349
VOP_WRITE(fffffd806aac6e78,ffff80002e6d7990,0,fffffd807f7d8a20) at VOP_WRITE+0xbf sys/kern/vfs_vops.c:245
uvn_io(fffffd806d39c380,ffff80002e6d7b20,6,31,1) at uvn_io+0x38a sys/uvm/uvm_vnode.c:1232
uvm_pager_put(fffffd806d39c380,fffffd8005f08f00,ffff80002e6d7bb8,ffff80002e6d7bf8,31,0,a8d79a02ea51a082) at uvm_pager_put+0x137 sys/uvm/uvm_pager.c:523
uvn_flush(fffffd806d39c380,0,0,31) at uvn_flush+0x52d sys/uvm/uvm_vnode.c:719
uvm_vnp_sync(ffff8000006d7000) at uvm_vnp_sync+0x15f sys/uvm/uvm_vnode.c:1503
sys_sync(ffff80002650b510,ffff80002e6d7d08,ffff80002e6d7d60) at sys_sync+0x9b sys/kern/vfs_syscalls.c:538
syscall(ffff80002e6d7dd0) at syscall+0x44e sys/arch/amd64/amd64/trap.c:585
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7cf0edcd760, count: 5
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