Actually it's not that obvious. If the actual problem
here (besides the mis-comparison) is due to missing
barriers or flushes. Avi asked a good question in that
thread.
It's obvious that it's a hack. It doesn't fix anything, it just disables a
feature that didn't work. Good for debugging, but not something that you
would like to commit.
It's reasonable to include something like this when we know that something is
broken but we haven't found it yet - but I believe Christoph's patch is the
real fix. If anyone can still find a case that is "fixed" by Avi's patch, I
could be convinced to apply it anyway, but I'd prefer if I didn't have to.
Note that we actually don't have overlapping requests. It just looks like it
because the qsort call doesn't work correctly with the broken comparison
function, so lower sector numbers can come after higher ones.