Hi Stefan,

applying patch [U-Boot,v4,06/13]ext4 and Michael Walles patch [U-Boot,v4,3/4]ext4, I'm now able to write into directories on ext4 fs from u-boot. However, when deleting a given file (i.e. when writing to an existing filename), u-boot crashes when ext4 extents are enabled.

Some debugging showd that blknr from 'read_allocated_block' function returns negative value. I can only guess, maybe its due to 64 bit values calculated from ee_start_hi and ee_start_lo entries in the ext4_extent structure.

When disabling extents in the ext4 fs, deleting a given file is working.

Best regards, Thomas Schäfer