"When the data corruption bug which is fixed as of 2.6.20-rc3 was still being tracked down, it was thought that the bug, a race in shared mmap'ed page writeback, might have been in the 2.6 kernel for a very long time. It has since been determined that the bug was introduced much more recently. Nick Piggin explains, 'this bug was only introduced in 2.6.19, due to a change that caused pte dirty bits to be discarded without a subsequent set_page_dirty() (nowhere else in the kernel should have done this)...'"
