How to flash Modified DTB for nano besides Jetpack

./flash.sh -r -k DTB jetson-nano-emmc mmcblk0p1

I burn DTB according to the above method and report the following error

[   0.0270 ] tegrarcm --chip 0x21 0 --updatesig rcm_list_signed.xml
[   0.0325 ] 
[   0.0327 ] Boot Rom communication
[   0.0354 ] tegrarcm --chip 0x21 0 --rcm rcm_list_signed.xml --skipuid
[   0.0371 ] RCM version 0X210001
[   0.2364 ] Boot Rom communication completed
[   1.2606 ] 
[   1.2607 ] dump EEPROM info
[   1.2623 ] tegrarcm --oem platformdetails eeprom /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/cvm.bin
[   1.2635 ] Applet version 00.01.0000
[   1.3950 ] Saved platform info in /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/cvm.bin
[   1.5154 ] 
Board ID(3448) version(400) 
copying bctfile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/t210ref/BCT/P3448_A00_lpddr4_204Mhz_P987.cfg)... done.
copying bootloader(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/t210ref/cboot.bin)... done.
copying initrd(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/l4t_initrd.img)... done.
	populating kernel to rootfs... done.
	populating initrd to rootfs... done.
	populating /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/kernel/dtb/tegra210-p3448-0000-p3449-0000-b00.dtb to rootfs... done.
Making Boot image... done.
Existing sosfile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/nvtboot_recovery.bin) reused.
copying tegraboot(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/t210ref/nvtboot.bin)... done.
copying cpu_bootloader(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/t210ref/cboot.bin)... done.
copying bpffile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/t210ref/sc7entry-firmware.bin)... done.
Existing badpagefile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/badpage.bin) reused.
copying wb0boot(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/t210ref/warmboot.bin)... done.
Existing tosfile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/tos-mon-only.img) reused.
Existing eksfile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/bootloader/eks.img) reused.
copying dtbfile(/home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/kernel/dtb/tegra210-p3448-0000-p3449-0000-b00.dtb)... done.
Copying nv_boot_control.conf to rootfs
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
sed: 无法读取 /home/jiazhiwne/test-nano-32.4.3/nano-kit/Linux_for_Tegra/rootfs/etc/nv_boot_control.conf: 不是目录
Reusing existing system.img... 
file does not exist.