On 2011-02-23 at 13:41-05 Peter Jones <pjones(a)redhat.com> wrote:
dm-crypt still just throws REQ_FLUSH away instead of figuring out
the block remaps involved and issuing the right bios. Of course,
this is a problem with dm-crypt and _any_ filesystem.
Are you sure that's still the case?
Because this patchset appears to add REQ_FLUSH support to dm:
http://www.redhat.com/archives/dm-devel/2010-August/msg00303.html
...and that patchset is included in 2.6.38-rc6.