nand flash打印[ND]fill block 是什么意思？

[abc3240574]

[ 1.486833] [ND]fill block 57
[ 1.487825] [ND]fill block 59
[ 1.489368] [ND]fill block 68
[ 1.490762] [ND]fill block 75
[ 1.498227] [ND]fill block 158
[ 1.501658] [ND]fill block 190
[ 1.507524] [ND]fill block 252
[ 1.509521] [ND]fill block 266
[ 1.513084] [ND]fill block 299
[ 1.523322] [ND]fill block 412
[ 1.524769] [ND]fill block 419
[ 1.525705] [ND]fill block 420
[ 1.527065] [ND]fill block 426
[ 1.533979] [ND]fill block 498
[ 1.543289] [ND]fill block 596
[ 1.549495] [ND]fill block 657
[ 1.553181] [ND]fill block 689
[ 1.554842] [ND]fill block 698
[ 1.560123] [ND]fill block 748
[ 1.566102] [ND]fill block 803
[ 1.575865] [ND]fill block 900
[ 1.577598] [ND]fill block 910
[ 1.579996] [ND]fill block 926
[ 1.584236] [ND]fill block 961
[ 1.585777] [ND]fill block 968
[ 1.588605] [ND]fill block 988
[ 1.590541] [ND]fill block 1000

nand flash出现很多这种打印是什么意思？