This is probably not as serious as the title implies, and apparently not related to the recent reports of EXT4 corruptions. Quoting [0] Theodore Ts'o: >So it's

This is probably not as serious as the title implies, and apparently not related to the recent reports of EXT4 corruptions. Quoting [0] Theodore Ts'o: >So it's pretty hard to hit this bug by accident >It requires the combination of (a) writing to a portion of a file that was not previously allocated using buffered I/O, (b) an fallocate of a region of the file which is a superset of region written in (a) before it has chance to be written to disk, (c) waiting for the file data in (a) to be written out to disk (either via fsync or via the writeback daemons), and then (d) before the extent status cache gets pushed out of memory, another random write to a portion of the file covered by (a) -- in which case that specific portion of (a) could be replaced by all zeros. [0] http://thread.gmane.org/gmane.linux.kernel/1956583 http://thread.gmane.org/gmane.linux.kernel/1956583