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在安装时 JFFS2 CLEANMARKER 大小从默认的 0x0C (12B) 更改为 0x0200 (512B)。
当我将测试映像安装在目标硬件（NOR）上时，我看到了这种行为，并且当我将任何文件复制到它时，文件系统大小以疯狂的方式增加。

测试台
我创建了一个 512kB 的“aa55”文件仅供参考，并用它创建了 JFFS2 文件系统未压缩映像（擦除块 128kB 页 4kB） 

dd if=<(yes $'\xaa55' |tr -d "\n") of=firma_512kB.txt bs=1024 count=512
mkdir firma/
cp firma
cp firma_512kB.txt firma/
sudo mkfs.jffs2 -v -o firma_512.jffs2 -e 0x20000 -s 0x1000 -m none -d firma/

在目标上，图像被复制到 mtd14。（之前被抹掉了，看CLEANMARKER的大小是0x0c） 

flash_eraseall -j /dev/mtd14
  00000000  85 19 03 20 0c 00 00 00  b1 b0 1e e4 ff ff ff ff  |... ............|
  00000010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
  *
  ...
  000a0000  85 19 03 20 0c 00 00 00  b1 b0 1e e4 ff ff ff ff  |... ............|
  000a0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
  *
  000c0000  85 19 03 20 0c 00 00 00  b1 b0 1e e4 ff ff ff ff  |... ............|
  000c0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
  *
  ...
  *
  00860000  85 19 03 20 0c 00 00 00  b1 b0 1e e4 ff ff ff ff  |... ............|
  00860010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
  *
  00880000

图像复制到 mtd15 设备并检查，显示...（可以看出图像复制正常，CLEANMARKER 大小仍为 0x0c）

dd if=firma_512.jffs2 of=/dev/mtd14  
hexdump -C /dev/mtd14  
(hexdump -C /dev/mtdblock14 gives the same result)

  ....
  00081340  85 19 02 e0 44 10 00 00  6d 58 d1 84 02 00 00 00  |....D...mX......|
  00081350  84 00 00 00 a4 81 00 00  e8 03 e8 03 00 00 08 00  |................|
  00081360  a3 dc df 53 a3 dc df 53  a3 dc df 53 00 f0 07 00  |...S...S...S....|
  00081370  00 10 00 00 00 10 00 00  00 00 00 00 db 7c 54 f0  |.............|T.|
  00081380  3c 30 bd 6f aa 55 aa 55  aa 55 aa 55 aa 55 aa 55  |<0.o.U.U.U.U.U.U|
  00081390  aa 55 aa 55 aa 55 aa 55  aa 55 aa 55 aa 55 aa 55  |.U.U.U.U.U.U.U.U|
  *
  00082380  aa 55 aa 55 ff ff ff ff  ff ff ff ff ff ff ff ff  |.U.U............|
  00082390  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
  *
  000a0000  85 19 03 20 0c 00 00 00  b1 b0 1e e4 ff ff ff ff  |... ............|
  000a0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
  *
  000c0000  85 19 03 20 0c 00 00 00  b1 b0 1e e4 ff ff ff ff  |... ............|
  000c0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|

现在是脑死亡问题，至少对我来说。mount -t jffs2 /dev/mtdblock14 /mnt/app2

  dmesg
     CLEANMARKER node found at 0x00000000 has totlen 0xc != normal 0x200
     ...
     CLEANMARKER node found at 0x000c0000 has totlen 0xc != normal 0x200
     CLEANMARKER node found at 0x000e0000 has totlen 0xc != normal 0x200
     ...
     CLEANMARKER node found at 0x00860000 has totlen 0xc != normal 0x200

  hexdump -C /dev/mtd14
     ....
     00081340  85 19 02 e0 44 10 00 00  6d 58 d1 84 02 00 00 00  |....D...mX......|
     00081350  84 00 00 00 a4 81 00 00  e8 03 e8 03 00 00 08 00  |................|
     00081360  a3 dc df 53 a3 dc df 53  a3 dc df 53 00 f0 07 00  |...S...S...S....|
     00081370  00 10 00 00 00 10 00 00  00 00 00 00 db 7c 54 f0  |.............|T.|
     00081380  3c 30 bd 6f aa 55 aa 55  aa 55 aa 55 aa 55 aa 55  |<0.o.U.U.U.U.U.U|
     00081390  aa 55 aa 55 aa 55 aa 55  aa 55 aa 55 aa 55 aa 55  |.U.U.U.U.U.U.U.U|
     *
     00082380  aa 55 aa 55 ff ff ff ff  ff ff ff ff ff ff ff ff  |.U.U............|
     00082390  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
     *
     000a0000  85 19 03 20 00 02 00 00  67 db 4c ad ff ff ff ff  |... ....g.L.....|
     000a0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
     *
     000c0000  85 19 03 20 00 02 00 00  67 db 4c ad ff ff ff ff  |... ....g.L.....|
     000c0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|
     *
     000e0000  85 19 03 20 00 02 00 00  67 db 4c ad ff ff ff ff  |... ....g.L.....|
     000e0010  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff  |................|

CLEANMARKER 尺寸变化不仅会造成混乱，而且会浪费设备中的大量空间。为什么在挂载时会更改？可以避免吗？

欢迎您的建议/建议

目标描述：
Linux-2.6.31
NOR：Spansion S29GL512S（擦除扇区 128kB 页面大小 4kB x16dBUS）

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