Comment 14 for bug 26528

In the new grub package 0.97-2, I no longer see the dreadful message

Error 21: Selected disk does not exist

when running grub unter a 2.4 kernel. AFICT, the only change that can be
responsible for this welcome change is the removal of the odirect.diff
patch, which was supposed to close #341888. And in the manpage for open(2)
I found the following statement about a difference between 2.4 and 2.6
kernelswhich supports this conjecture:

 O_DIRECT
  Try to minimize cache effects of the I/O to and from this file.
  In general this will degrade performance, but it is useful in
  special situations, such as when applications do their own
  caching. File I/O is done directly to/from user space buffers.
  The I/O is synchronous, i.e., at the completion of a read(2) or
  write(2), data is guaranteed to have been transferred. Under
  Linux 2.4 transfer sizes, and the alignment of user buffer and
  file offset must all be multiples of the logical block size of
  the file system. Under Linux 2.6 alignment to 512-byte boundaries
  suffices.

So it seems that the odirect.diff patch introduced the problem, and since
it has been removed I'm closing this bug.